Sample records for ghz microwave radiometer

  1. Microwave Radiometer (MWR) Handbook

    SciTech Connect (OSTI)

    Morris, VR

    2006-08-01T23:59:59.000Z

    The Microwave Radiometer (MWR) provides time-series measurements of column-integrated amounts of water vapor and liquid water. The instrument itself is essentially a sensitive microwave receiver. That is, it is tuned to measure the microwave emissions of the vapor and liquid water molecules in the atmosphere at specific frequencies.

  2. Microwave Radiometer-High Frequency (MWRHF) Handbook

    SciTech Connect (OSTI)

    Caddedu, MP

    2011-03-17T23:59:59.000Z

    The 90/150-GHz Vapor Radiometer provides time-series measurements of brightness temperatures from two channels centered at 90 and 150 GHz. These two channels are sensitive to the presence of liquid water and precipitable water vapor.

  3. Microwave Radiometer – 3 Channel (MWR3C) Handbook

    SciTech Connect (OSTI)

    Cadeddu, MP

    2012-05-04T23:59:59.000Z

    The microwave radiometer 3-channel (MWR3C) provides time-series measurements of brightness temperatures from three channels centered at 23.834, 30, and 89 GHz. These three channels are sensitive to the presence of liquid water and precipitable water vapor.

  4. ARM - Field Campaign - Microwave Radiometer Profiler Evaluation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa- Polarization Diversity Lidar (PDL) CampaigngovCampaignsMicrowave Radiometer Profiler

  5. ARM: Microwave Radiometer data (MWR Profiles - QME), water vapor, temp, cloud liquid water, precip water retrievals

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Cadeddu, Maria

    Microwave Radiometer data (MWR Profiles - QME), water vapor, temp, cloud liquid water, precip water retrievals

  6. MICROWAVE RADIOMETER INTER-CALIBRATION USING THE VICARIOUS CALIBRATION METHOD

    E-Print Network [OSTI]

    Ruf, Christopher

    MICROWAVE RADIOMETER INTER-CALIBRATION USING THE VICARIOUS CALIBRATION METHOD Darren McKague Chris Ruf John J. Puckett University of Michigan ABSTRACT The vicarious cold and warm calibration methods of Ruf, and Brown and Ruf, have been used to assess the calibration of the WindSat radiometer as well

  7. Remote monitoring of soil moisture using airborne microwave radiometers

    E-Print Network [OSTI]

    Kroll, Charles Lindsey

    1973-01-01T23:59:59.000Z

    REMOTE MONITORING OF SOIL MOISTURE USING AIRBORNE MICROWAVE RADIOMETERS A Thesis by CHARLES LINDSEY J(ROLL Submitted to the Graduate College of Texas A)M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE... August 1973 Major Subject: Electrical Engineering REMOTE MONITORING OF SOIL MOISTURE USING AIRBORNE MICROWAVE RADIOMETERS A Thesis by CHARLES LINDSEY KROLL Approved as to style and content by: man o Co mrtt Hca o D artmc c Ill l c r Mem e Member...

  8. Using a co-located GNSS radio occultation payload for microwave radiometer calibration

    E-Print Network [OSTI]

    Davé, Pratik K. (Pratik Kamlesh)

    2014-01-01T23:59:59.000Z

    This study presents a new method of calibrating an orbital cross-track scanning microwave radiometer using a co-located radio occultation (RO) instrument with Global Navigation Satellite Systems (GNSS). The radiometer and ...

  9. Preliminary separation of galactic and cosmic microwave emission for the COBE Differential Microwave Radiometer

    SciTech Connect (OSTI)

    Bennet, C.L.; Smoot, G.F.; Hinshaw, G.; Wright, E.L.; Kogut, A.; De Amici, G.; Meyer, S.S.; Weiss, R.; Wilkinson, D.T.; Gulkis, S. (NASA, Goddard Space Flight Center, Greenbelt, MD (United States) Lawrence Berkeley Laboratory, CA (United States) California, University, Berkeley (United States) Universities Space Research Association, Boulder, CO (United States) California, University, Los Angeles (United States) MIT, Cambridge, MA (United States) Princeton University, NJ (United States) JPL, Pasadena, Ca (United States))

    1992-09-01T23:59:59.000Z

    Preliminary models of microwave emission from the Milky Way Galaxy based on COBE and other data are constructed for the purpose of distinguishing cosmic and Galactic signals. Differential Microwave Radiometer (DMR) maps, with the modeled Galactic emission removed, are fitted for a quadrupole distribution. Autocorrelation functions for individual Galactic components are presented. When Galactic emission is removed from the DMR data, the residual fluctuations are virtually unaffected, and therefore they are not dominated by any known Galactic emission component. 42 refs.

  10. Dual frequency microwave radiometer measurements of soil moisture for bare and vegetated rough surfaces

    E-Print Network [OSTI]

    Lee, Siu Lim

    1974-01-01T23:59:59.000Z

    DUAL FREQUENCY MICROWAVE RADIOMETER MEASUREMENTS OF SOIL MOISTURE FOR BARE AND VEGETATED ROUGH SURFACES A Thesis by SIU LIM LEE Submitted to the Graduate College of Texas A(M University in partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE August 1974 Major Subject: Electrical Engineering DUAL FREQUENCY MICROWAVE RADIOMETER MEASUREMENTS OF' SOIL MOISTURE FOR BARE AND VEGETATED ROUGH SURFACES A Thesis by SIU LIM LEE Approved as to style and content by: (C rman...

  11. Calibration of a Fully Polarimetric Microwave Radiometer Using a Digital Polarimeric Noise Source

    E-Print Network [OSTI]

    Ruf, Christopher

    Calibration of a Fully Polarimetric Microwave Radiometer Using a Digital Polarimeric Noise Source-936-0503 (F), bhlim@umich.edu / cruf@umich.edu (E) Abstract ­ The Correlated Noise Calibration Standard (CNCS polarization mixing calibration equation for AESMIR. Absolute calibration accuracy of AESMIR is estimated

  12. 140 GHz pulsed Fourier transform microwave spectrometer

    DOE Patents [OSTI]

    Kolbe, W.F.; Leskovar, B.

    1985-07-29T23:59:59.000Z

    A high frequency energy pulsing system suitable for use in a pulsed microwave spectrometer, including means for generating a high frequency carrier signal, and means for generating a low frequency modulating signal. The carrier signal is continuously fed to a modulator and the modulating signal is fed through a pulse switch to the modulator. When the pulse switch is on, the modulator will produce sideband signals above and below the carrier signal frequency. A frequency-responsive device is tuned to one of the sideband signals and sway from the carrier frequency so that the high frequency energization of the frequency-responsive device is controlled by the pulse switch.

  13. 140 GHz pulsed Fourier transform microwave spectrometer

    DOE Patents [OSTI]

    Kolbe, W.F.; Leskovar, B.

    1987-10-27T23:59:59.000Z

    A high frequency energy pulsing system suitable for use in a pulsed microwave spectrometer, including means for generating a high frequency carrier signal, and means for generating a low frequency modulating signal is disclosed. The carrier signal is continuously fed to a modulator and the modulating signal is fed through a pulse switch to the modulator. When the pulse switch is on, the modulator will produce sideband signals above and below the carrier signal frequency. A frequency-responsive device is tuned to one of the sideband signals and away from the carrier frequency so that the high frequency energization of the frequency-responsive device is controlled by the pulse switch. 5 figs.

  14. 140 GHz pulsed fourier transform microwave spectrometer

    DOE Patents [OSTI]

    Kolbe, William F. (Oakland, CA); Leskovar, Branko (Moraga, CA)

    1987-01-01T23:59:59.000Z

    A high frequency energy pulsing system suitable for use in a pulsed microwave spectrometer (10), including means (11, 19) for generating a high frequency carrier signal, and means (12) for generating a low frequency modulating signal. The carrier signal is continuously fed to a modulator (20) and the modulating signal is fed through a pulse switch (23) to the modulator. When the pulse switch (23) is on, the modulator (20) will produce sideband signals above and below the carrier signal frequency. A frequency-responsive device (31) is tuned to one of the sideband signals and away from the carrier frequency so that the high frequency energization of the frequency-responsive device (31) is controlled by the pulse switch (23).

  15. Land Contamination Correction for Passive Microwave Radiometer Data: Demonstration of Wind Retrieval in the Great Lakes Using SSM/I

    E-Print Network [OSTI]

    Ruf, Christopher

    Land Contamination Correction for Passive Microwave Radiometer Data: Demonstration of Wind, are typically unavailable within about 100km of any coastline. This paper presents methods of cor- recting land-contaminated radiometer data in order to extract the coastal information. The land contamination signals are estimated

  16. ARM - Midlatitude Continental Convective Clouds Microwave Radiometer Profiler (jensen-mwr)

    SciTech Connect (OSTI)

    Jensen, Mike

    2012-02-01T23:59:59.000Z

    A major component of the Mid-latitude Continental Convective Clouds Experiment (MC3E) field campaign was the deployment of an enhanced radiosonde array designed to capture the vertical profile of atmospheric state variables (pressure, temperature, humidity wind speed and wind direction) for the purpose of deriving the large-scale forcing for use in modeling studies. The radiosonde array included six sites (enhanced Central Facility [CF-1] plus five new sites) launching radiosondes at 3-6 hour sampling intervals. The network will cover an area of approximately (300)2 km2 with five outer sounding launch sites and one central launch location. The five outer sounding launch sites are: S01 Pratt, KS [ 37.7oN, 98.75oW]; S02 Chanute, KS [37.674, 95.488]; S03 Vici, Oklahoma [36.071, -99.204]; S04 Morris, Oklahoma [35.687, -95.856]; and S05 Purcell, Oklahoma [34.985, -97.522]. Soundings from the SGP Central Facility during MC3E can be retrieved from the regular ARM archive. During routine MC3E operations 4 radiosondes were launched from each of these sites (approx. 0130, 0730, 1330 and 1930 UTC). On days that were forecast to be convective up to four additional launches were launched at each site (approx. 0430, 1030, 1630, 2230 UTC). There were a total of approximately 14 of these high frequency launch days over the course of the experiment. These files contain brightness temperatures observed at Purcell during MC3E. The measurements were made with a 5 channel (22.235, 23.035, 23.835, 26.235, 30.000GHz) microwave radiometer at one minute intervals. The results have been separated into daily files and the day of observations is indicated in the file name. All observations were zenith pointing. Included in the files are the time variables base_time and time_offset. These follow the ARM time conventions. Base_time is the number seconds since January 1, 1970 at 00:00:00 for the first data point of the file and time_offset is the offset in seconds from base_time.

  17. ARM - Midlatitude Continental Convective Clouds Microwave Radiometer Profiler (jensen-mwr)

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Jensen, Mike

    A major component of the Mid-latitude Continental Convective Clouds Experiment (MC3E) field campaign was the deployment of an enhanced radiosonde array designed to capture the vertical profile of atmospheric state variables (pressure, temperature, humidity wind speed and wind direction) for the purpose of deriving the large-scale forcing for use in modeling studies. The radiosonde array included six sites (enhanced Central Facility [CF-1] plus five new sites) launching radiosondes at 3-6 hour sampling intervals. The network will cover an area of approximately (300)2 km2 with five outer sounding launch sites and one central launch location. The five outer sounding launch sites are: S01 Pratt, KS [ 37.7oN, 98.75oW]; S02 Chanute, KS [37.674, 95.488]; S03 Vici, Oklahoma [36.071, -99.204]; S04 Morris, Oklahoma [35.687, -95.856]; and S05 Purcell, Oklahoma [34.985, -97.522]. Soundings from the SGP Central Facility during MC3E can be retrieved from the regular ARM archive. During routine MC3E operations 4 radiosondes were launched from each of these sites (approx. 0130, 0730, 1330 and 1930 UTC). On days that were forecast to be convective up to four additional launches were launched at each site (approx. 0430, 1030, 1630, 2230 UTC). There were a total of approximately 14 of these high frequency launch days over the course of the experiment. These files contain brightness temperatures observed at Purcell during MC3E. The measurements were made with a 5 channel (22.235, 23.035, 23.835, 26.235, 30.000GHz) microwave radiometer at one minute intervals. The results have been separated into daily files and the day of observations is indicated in the file name. All observations were zenith pointing. Included in the files are the time variables base_time and time_offset. These follow the ARM time conventions. Base_time is the number seconds since January 1, 1970 at 00:00:00 for the first data point of the file and time_offset is the offset in seconds from base_time.

  18. 3742 IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 47, NO. 11, NOVEMBER 2009 Microwave Radiometer Radio-Frequency

    E-Print Network [OSTI]

    Ruf, Christopher

    Radiometer Radio-Frequency Interference Detection Algorithms: A Comparative Study Sidharth Misra, Priscilla N is with Halliburton Energy Services, Houston, TX 77032 USA. J. R. Piepmeier is with the Microwave Instrument growth recently in satellite telecommunica- tion, in high-bandwidth point-to-point terrestrial wireless

  19. 314 IEEE MICROWAVE AND GUIDED WAVE LETTERS, VOL. 9, NO. 8, AUGUST 1999 39-GHz GaN-Based Microwave Power

    E-Print Network [OSTI]

    York, Robert A.

    314 IEEE MICROWAVE AND GUIDED WAVE LETTERS, VOL. 9, NO. 8, AUGUST 1999 3­9-GHz GaN-Based Microwave. P. Keller, and U. K. Mishra, Fellow, IEEE Abstract--We present an initial demonstration of GaN-band network. Using 0.7-m gate-length GaN high-electron-mobility transistors (HEMT's) with current

  20. Design and implementation of a digitally controlled multi-frequency microwave radiometer

    E-Print Network [OSTI]

    Warren, Gary Lynn

    1985-01-01T23:59:59.000Z

    . 21. Task-Exchange Diagram for DVMAIN Page 14 16 17 24 . 29 32 34 36 48 56 59 62 64 91 92 93 . 105 LIST OF SCHEWLTICS Schematics 1. Switch Decoder and Driver. 2. Motor Controller Hoard . . 3. Cold Load Controller . . . 4. Hot... of the software for radiometer control and data recording. TABLE OF CONTENTS ABSTRACT. . . . . . . . . . . . * TABLE OF CONTENTS LIST OF TABLES. LIST OF FIGURES LIST OF SCHEMATICS. CHAPTER I. INTRODUCTION. 1. 1 BACKGROUND . 1. 2 RADIOMETRY...

  1. Design and development of an airborne microwave radiometer for atmospheric sensing

    E-Print Network [OSTI]

    Scarito, Michael P

    2011-01-01T23:59:59.000Z

    Satellite-based passive microwave remote sensing is a valuable tool for global weather monitoring and prediction. This thesis presents the design and development of a low-cost airborne weather sensing instrument to ...

  2. Hydrologic data assimilation of multi-resolution microwave radiometer and radar measurements using ensemble smoothing

    E-Print Network [OSTI]

    Dunne, Susan Catherine

    2006-01-01T23:59:59.000Z

    Previously, the ensemble Kalman filter (EnKF) has been used to estimate soil moisture and related fluxes by merging noisy low frequency microwave observations with forecasts from a conventional though uncertain land surface ...

  3. Surface soil moisture estimation with the electrically scanning microwave radiometer (ESMR)

    E-Print Network [OSTI]

    Theis, Sidney Wayne

    1979-01-01T23:59:59.000Z

    that is important in determining the ability of a plant to uptake water and that determines the state of saturation of a soil. Matric potential is very important for crop modeling and runoff prediction. Roe et al. (1971) observed that the emissivity of a mooth... that were approximately 15 to 20 cm high. For an area covered with thick turfted grass to a height of 20 cm, Barton (1978) obtained a poor relationship between soil moisture and emissivity for both the ESHR and a 2. 65-cm radiometer. The ESHR response...

  4. G-Band Vapor Radiometer Profiler (GVRP) Handbook

    SciTech Connect (OSTI)

    Caddeau, MP

    2010-06-23T23:59:59.000Z

    The G-Band Vapor Radiometer Profiler (GVRP) provides time-series measurements of brightness temperatures from 15 channels between 170 and 183.310 GHz. Atmospheric emission in this spectral region is primarily due to water vapor, with some influence from liquid water. Channels between 170.0 and 176.0 GHz are particularly sensitive to the presence of liquid water. The sensitivity to water vapor of the 183.31-GHz line is approximately 30 times higher than at the frequencies of the two-channel microwave radiometer (MWR) for a precipitable water vapor (PWV) amount of less than 2.5 mm. Measurements from the GVRP instrument are therefore especially useful during low-humidity conditions (PWV < 5 mm). In addition to integrated water vapor and liquid water, the GVRP can provide low-resolution vertical profiles of water vapor in very dry conditions.

  5. MWRRET Value-Added Product: The Retrieval of Liquid Water Path and Precipitable Water Vapor from Microwave Radiometer (MWR) Data Sets (Revision 2)

    SciTech Connect (OSTI)

    Gaustad, KL; Turner, DD; McFarlane, SA

    2011-07-25T23:59:59.000Z

    This report provides a short description of the Atmospheric Radiation Measurement (ARM) Climate Research Facility microwave radiometer (MWR) Retrieval (MWRRET) value-added product (VAP) algorithm. This algorithm utilizes a complementary physical retrieval method and applies brightness temperature offsets to reduce spurious liquid water path (LWP) bias in clear skies resulting in significantly improved precipitable water vapor (PWV) and LWP retrievals. We present a general overview of the technique, input parameters, output products, and describe data quality checks. A more complete discussion of the theory and results is given in Turner et al. (2007b).

  6. The Microwave Air Yield Beam Experiment (MAYBE): measurement of GHz radiation for Ultra-High Energy Cosmic Rays detection

    E-Print Network [OSTI]

    M. Monasor; M. Bohacova; C. Bonifazi; G. Cataldi; S. Chemerisov; J. R. T. De Mello Neto; P. Facal San Luis; B. Fox; P. W. Gorham; C. Hojvat; N. Hollon; R. Meyhandan; L. C. Reyes; B. Rouille D'Orfeuil; E. M. Santos; J. Pochez; P. Privitera; H. Spinka; V. Verzi; C. Williams; J. Zhou

    2011-08-31T23:59:59.000Z

    We present first measurements by MAYBE of microwave emission from an electron beam induced air plasma, performed at the electron Van de Graaff facility of the Argonne National Laboratory. Coherent radio Cherenkov, a major background in a previous beam experiment, is not produced by the 3 MeV beam, which simplifies the interpretation of the data. Radio emission is studied over a wide range of frequencies between 3 and 12 GHz. This measurement provides further insight on microwave emission from extensive air showers as a novel detection technique for Ultra-High Energy Cosmic Rays.

  7. SECOND SEASON QUIET OBSERVATIONS: MEASUREMENTS OF THE COSMIC MICROWAVE BACKGROUND POLARIZATION POWER SPECTRUM AT 95 GHz

    SciTech Connect (OSTI)

    Araujo, D.; Dumoulin, R. N.; Newburgh, L. B.; Zwart, J. T. L. [Department of Physics and Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Bischoff, C.; Brizius, A.; Buder, I.; Kusaka, A. [Kavli Institute for Cosmological Physics, Department of Physics, Enrico Fermi Institute, The University of Chicago, Chicago, IL 60637 (United States); Chinone, Y. [High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Cleary, K.; Reeves, R. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, 1200 E. California Blvd M/C 249-17, Pasadena, CA 91125 (United States); Monsalve, R.; Bustos, R. [Department of Physics, University of Miami, 1320 Campo Sano Drive, Coral Gables, FL 33146 (United States); Naess, S. K.; Eriksen, H. K. [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, NO-0315 Oslo (Norway); Wehus, I. K. [Department of Astrophysics, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom); Bronfman, L. [Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago (Chile); Church, S. E. [Kavli Institute for Particle Astrophysics and Cosmology and Department of Physics, Stanford University, Varian Physics Building, 382 Via Pueblo Mall, Stanford, CA 94305 (United States); Dickinson, C. [Jodrell Bank Centre for Astrophysics, Alan Turing Building, School of Physics and Astronomy, The University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom); Gaier, T., E-mail: ibuder@uchicago.edu [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Collaboration: QUIET Collaboration; and others

    2012-12-01T23:59:59.000Z

    The Q/U Imaging ExperimenT (QUIET) has observed the cosmic microwave background (CMB) at 43 and 95 GHz. The 43 GHz results have been published in a previous paper, and here we report the measurement of CMB polarization power spectra using the 95 GHz data. This data set comprises 5337 hr of observations recorded by an array of 84 polarized coherent receivers with a total array sensitivity of 87 {mu}K{radical}s. Four low-foreground fields were observed, covering a total of {approx}1000 deg{sup 2} with an effective angular resolution of 12.'8, allowing for constraints on primordial gravitational waves and high signal-to-noise measurements of the E-modes across three acoustic peaks. The data reduction was performed using two independent analysis pipelines, one based on a pseudo-C {sub l} (PCL) cross-correlation approach, and the other on a maximum-likelihood (ML) approach. All data selection criteria and filters were modified until a predefined set of null tests had been satisfied before inspecting any non-null power spectrum. The results derived by the two pipelines are in good agreement. We characterize the EE, EB, and BB power spectra between l = 25 and 975 and find that the EE spectrum is consistent with {Lambda}CDM, while the BB power spectrum is consistent with zero. Based on these measurements, we constrain the tensor-to-scalar ratio to r = 1.1{sup +0.9} {sub -0.8} (r < 2.8 at 95% C.L.) as derived by the ML pipeline, and r = 1.2{sup +0.9} {sub -0.8} (r < 2.7 at 95% C.L.) as derived by the PCL pipeline. In one of the fields, we find a correlation with the dust component of the Planck Sky Model, though the corresponding excess power is small compared to statistical errors. Finally, we derive limits on all known systematic errors, and demonstrate that these correspond to a tensor-to-scalar ratio smaller than r = 0.01, the lowest level yet reported in the literature.

  8. A Cloud Detection Algorithm using the Downwelling Infrared Radiance Measured by an Infrared Pyrometer of the Ground-based Microwave Radiometer

    SciTech Connect (OSTI)

    Ahn, M. H.; Han, D.; Won, H. Y.; Morris, Victor R.

    2015-01-01T23:59:59.000Z

    For a better utilization of the ground-based microwave radiometer, it is important to detect the cloud presence in the measured data. Here, we introduce a simple and fast cloud detection algorithm by using the optical characteristics of the clouds in the infrared atmospheric window region. The new algorithm utilizes the brightness temperature (Tb) measured by an infrared radiometer installed on top of a microwave radiometer. The two step algorithm consists of a spectral test followed by a temporal test. The measured Tb is first compared with a predicted clear sky Tb obtained by an empirical formula as a function of surface air temperature and water vapor pressure. For the temporal test, the temporal variability of the measured Tb during one minute compares with a dynamic threshold value, representing the variability of the clear sky condition. It is designated as cloud free data only when both the spectral and temporal tests confirm a cloud free data. Overall, most of the thick and uniform clouds are successfully screened out by the spectral test, while the broken and fast-varying clouds are screened out by the temporal test. The algorithm is validated by comparison with the collocated ceilometer data for 6 months, from January 2013 to June 2013. The overall proportion correct is about 88.3% and the probability of detection is 90.8 %, which are comparable with or better than those of previous similar approaches. Two thirds of failures occur when the new algorithm detects clouds while the ceilometer does not detect, resulting in different values of the probability of detection with different cloud base altitude, 93.8, 90.3, and 82.8% for low, mid, and high clouds, respectively. Finally, due to the characteristics of the spectral range, the new algorithm is found to be insensitive to the presence of inversion layers.

  9. A cloud detection algorithm using the downwelling infrared radiance measured by an infrared pyrometer of the ground-based microwave radiometer

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ahn, M.-H.; Han, D.; Won, H. Y.; Morris, V.

    2015-01-01T23:59:59.000Z

    For better utilization of the ground-based microwave radiometer, it is important to detect the cloud presence in the measured data. Here, we introduce a simple and fast cloud detection algorithm by using the optical characteristics of the clouds in the infrared atmospheric window region. The new algorithm utilizes the brightness temperature (Tb) measured by an infrared radiometer installed on top of a microwave radiometer. The two-step algorithm consists of a spectral test followed by a temporal test. The measured Tb is first compared with a predicted clear-sky Tb obtained by an empirical formula as a function of surface air temperaturemore »and water vapor pressure. For the temporal test, the temporal variability of the measured Tb during one minute compares with a dynamic threshold value, representing the variability of clear-sky conditions. It is designated as cloud-free data only when both the spectral and temporal tests confirm cloud-free data. Overall, most of the thick and uniform clouds are successfully detected by the spectral test, while the broken and fast-varying clouds are detected by the temporal test. The algorithm is validated by comparison with the collocated ceilometer data for six months, from January to June 2013. The overall proportion of correctness is about 88.3% and the probability of detection is 90.8%, which are comparable with or better than those of previous similar approaches. Two thirds of discrepancies occur when the new algorithm detects clouds while the ceilometer does not, resulting in different values of the probability of detection with different cloud-base altitude, 93.8, 90.3, and 82.8% for low, mid, and high clouds, respectively. Finally, due to the characteristics of the spectral range, the new algorithm is found to be insensitive to the presence of inversion layers.« less

  10. MWRRET (Microwave Radiometer Retrievals)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9November 6, InaprilU . S . DMTBEMU

  11. Empirical Evaluation of Four Microwave Radiative Forward Models Based on Ground-Based Radiometer Data Near 20 and 30 GHz

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField Campaign:INEAWater UseCElizabethTwo States CARLSBAD,EmilioRon

  12. Behavior of microwave-heated silicon carbide particles at frequencies of 2.0–13.5?GHz

    SciTech Connect (OSTI)

    Sugawara, H.; Hayashi, M.; Ishihara, S. [Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology, Ookayama 2-12-1, Meguro, Tokyo 152-8552 (Japan); Kashimura, K., E-mail: kashimura@isc.chubu.ac.jp [Chubu University, 1200 Matsumoto-cho, Kasugai, Aichi 487-8501 (Japan); Mitani, T.; Shinohara, N. [Kyoto University, Gokasyo, Uji, Kyoto 611-0011 (Japan)

    2014-07-21T23:59:59.000Z

    Silicon carbide is a key material in microwave (MW) processing and is used widely as a thermal insulator and catalytic agent. In this study, we experimentally investigated the temperature dependence of the MW-absorption properties of SiC particles at frequencies of 2.0–13.5?GHz. We heated SiC particles of different sizes using MW radiation. The heating behaviors of the particles were then compared with their MW-absorption properties. The heating behavior of the particles was dependent on their radii; this result was in keeping with theoretical predictions. Furthermore, the ?-SiC particles exhibited anomalous behaviors when subjected to microwave heating at temperatures of 1100?°C and higher. These behaviors were attributable to the transformation of ?-SiC into the ?-phase. The underlying mechanism for this transformation is discussed on the basis of the results of X-ray diffraction analysis.

  13. JOURNAL OF GEOPHYSICAL RESEARCH, VOL. ???, XXXX, DOI:10.1029/, Sea Ice Remote Sensing Using AMSR-E 89 GHz Channels

    E-Print Network [OSTI]

    Bremen, Universität

    JOURNAL OF GEOPHYSICAL RESEARCH, VOL. ???, XXXX, DOI:10.1029/, Sea Ice Remote Sensing Using AMSR progress in sea ice concentration remote sensing by satellite microwave radiometers has been stimulated, a new algorithm enables to estimate sea ice concentration from the channels near 90 GHz, despite the en

  14. IMPROVED MICROWAVE REMOTE SENSING OF HURRICANE WIND SPEED AND RAIN RATES USING THE HURRICANE IMAGING RADIOMETER (HIRAD)

    E-Print Network [OSTI]

    Ruf, Christopher

    IMPROVED MICROWAVE REMOTE SENSING OF HURRICANE WIND SPEED AND RAIN RATES USING THE HURRICANE) that measures wind speed and rain rate along the ground track directly beneath the aircraft. This paper presents are presented, which illustrate wind speed and rain rate measurement spatial resolutions and swath coverage. 1

  15. High spatial resolution upgrade of the electron cyclotron emission radiometer for the DIII-D tokamak

    SciTech Connect (OSTI)

    Truong, D. D., E-mail: dtruong@wisc.edu [Department of Engineering Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Austin, M. E. [Institute for Fusion Studies, University of Texas, Austin, Texas, 78712 (United States)

    2014-11-15T23:59:59.000Z

    The 40-channel DIII-D electron cyclotron emission (ECE) radiometer provides measurements of T{sub e}(r,t) at the tokamak midplane from optically thick, second harmonic X-mode emission over a frequency range of 83–130 GHz. The frequency spacing of the radiometer's channels results in a spatial resolution of ?1–3 cm, depending on local magnetic field and electron temperature. A new high resolution subsystem has been added to the DIII-D ECE radiometer to make sub-centimeter (0.6–0.8 cm) resolution T{sub e} measurements. The high resolution subsystem branches off from the regular channels’ IF bands and consists of a microwave switch to toggle between IF bands, a switched filter bank for frequency selectivity, an adjustable local oscillator and mixer for further frequency down-conversion, and a set of eight microwave filters in the 2–4 GHz range. Higher spatial resolution is achieved through the use of a narrower (200 MHz) filter bandwidth and closer spacing between the filters’ center frequencies (250 MHz). This configuration allows for full coverage of the 83–130 GHz frequency range in 2 GHz bands. Depending on the local magnetic field, this translates into a “zoomed-in” analysis of a ?2–4 cm radial region. Expected uses of these channels include mapping the spatial dependence of Alfven eigenmodes, geodesic acoustic modes, and externally applied magnetic perturbations. Initial T{sub e} measurements, which demonstrate that the desired resolution is achieved, are presented.

  16. IEEE MICROWAVE AND GUIDED WAVE LETTERS, VOL. 9, NO. 7, JULY 1999 277 18-GHz GaN-Based Power Amplifier

    E-Print Network [OSTI]

    York, Robert A.

    IEEE MICROWAVE AND GUIDED WAVE LETTERS, VOL. 9, NO. 7, JULY 1999 277 1­8-GHz GaN-Based Power, Senior Member, IEEE Abstract-- We report the first gallium nitride (GaN)-based broad-band power amplifier. The circuit was fabricated on an AlN substrate using AlGaN/GaN power high-electron mobil- ity transistors

  17. Broadband radiometer

    DOE Patents [OSTI]

    Cannon, T.W.

    1994-07-26T23:59:59.000Z

    A broadband radiometer is disclosed including (a) an optical integrating sphere having generally spherical integrating chamber and an entry port for receiving light (e.g., having visible and ultraviolet fractions), (b) a first optical radiation detector for receiving light from the sphere and producing an electrical output signal corresponding to broadband radiation, (c) a second optical radiation detector for receiving light from the sphere and producing an electrical output signal corresponding to a predetermined wavelength fraction of the broadband radiation, and (d) an output for producing an electrical signal which is proportional to the difference between the two electrical output signals. The radiometer is very useful, for example, in measuring the absolute amount of ultraviolet light present in a given light sample. 8 figs.

  18. DRAFT Microwave Radiometer Profiler Handbook

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power Administration wouldDECOMPOSITION OFSupplemental Technology TestingDiscussion after

  19. Influence of microwave driver coupling design on plasma density at Testbench for Ion sources Plasma Studies, a 2.45 GHz Electron Cyclotron Resonance Plasma Reactor

    SciTech Connect (OSTI)

    Megía-Macías, A.; Vizcaíno-de-Julián, A. [E.S.S. Bilbao, Edificio Cosimet, Landabarri 2, 48940-Leioa, Vizcaya (Spain)] [E.S.S. Bilbao, Edificio Cosimet, Landabarri 2, 48940-Leioa, Vizcaya (Spain); Cortázar, O. D., E-mail: dcortazar@essbilbao.org [E.S.S. Bilbao, Edificio Cosimet, Landabarri 2, 48940-Leioa, Vizcaya (Spain); Universidad de Castilla-La Mancha, ETSII, C.J. Cela s/n, 13170 Ciudad Real (Spain)

    2014-03-15T23:59:59.000Z

    A comparative study of two microwave driver systems (preliminary and optimized) for a 2.45 GHz hydrogen Electron Cyclotron Resonance plasma generator has been conducted. The influence on plasma behavior and parameters of stationary electric field distribution in vacuum, i.e., just before breakdown, along all the microwave excitation system is analyzed. 3D simulations of resonant stationary electric field distributions, 2D simulations of external magnetic field mapping, experimental measurements of incoming and reflected power, and electron temperature and density along the plasma chamber axis have been carried out. By using these tools, an optimized set of plasma chamber and microwave coupler has been designed paying special attention to the optimization of stationary electric field value in the center of the plasma chamber. This system shows a strong stability on plasma behavior allowing a wider range of operational parameters and even sustaining low density plasma formation without external magnetic field. In addition, the optimized system shows the capability to produce values of plasma density four times higher than the preliminary as a consequence of a deeper penetration of the magnetic resonance surface in relative high electric field zone by keeping plasma stability. The increment of the amount of resonance surface embedded in the plasma under high electric field is suggested as a key factor.

  20. FIRST SEASON QUIET OBSERVATIONS: MEASUREMENTS OF COSMIC MICROWAVE BACKGROUND POLARIZATION POWER SPECTRA AT 43 GHz IN THE MULTIPOLE RANGE 25 {<=} l {<=} 475

    SciTech Connect (OSTI)

    Bischoff, C.; Brizius, A.; Buder, I.; Kusaka, A.; Smith, K. M. [Kavli Institute for Cosmological Physics, Department of Physics, Enrico Fermi Institute, University of Chicago, Chicago, IL 60637 (United States); Chinone, Y. [High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801 (Japan); Cleary, K.; Reeves, R. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Dumoulin, R. N.; Newburgh, L. B.; Zwart, J. T. L. [Department of Physics and Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Monsalve, R.; Bustos, R. [Department of Physics, University of Miami, Coral Gables, FL 33146 (United States); Naess, S. K.; Eriksen, H. K. [Institute of Theoretical Astrophysics, University of Oslo, N-0315 Oslo (Norway); Wehus, I. K. [Department of Physics, University of Oslo, N-0316 Oslo (Norway); Zuntz, J. A. [Department of Astrophysics, University of Oxford, Oxford OX1 3RH (United Kingdom); Bronfman, L. [Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago (Chile); Church, S. E. [Kavli Institute for Particle Astrophysics and Cosmology and Department of Physics, Stanford University, Varian Physics Building, Stanford, CA 94305 (United States); Dickinson, C., E-mail: akito@kicp.uchicago.edu [Jodrell Bank Centre for Astrophysics, Alan Turing Building, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom)

    2011-11-10T23:59:59.000Z

    The Q/U Imaging ExperimenT (QUIET) employs coherent receivers at 43 GHz and 94 GHz, operating on the Chajnantor plateau in the Atacama Desert in Chile, to measure the anisotropy in the polarization of the cosmic microwave background (CMB). QUIET primarily targets the B modes from primordial gravitational waves. The combination of these frequencies gives sensitivity to foreground contributions from diffuse Galactic synchrotron radiation. Between 2008 October and 2010 December, over 10,000 hr of data were collected, first with the 19 element 43 GHz array (3458 hr) and then with the 90 element 94 GHz array. Each array observes the same four fields, selected for low foregrounds, together covering Almost-Equal-To 1000 deg{sup 2}. This paper reports initial results from the 43 GHz receiver, which has an array sensitivity to CMB fluctuations of 69 {mu}K{radical}s. The data were extensively studied with a large suite of null tests before the power spectra, determined with two independent pipelines, were examined. Analysis choices, including data selection, were modified until the null tests passed. Cross-correlating maps with different telescope pointings is used to eliminate a bias. This paper reports the EE, BB, and EB power spectra in the multipole range l = 25-475. With the exception of the lowest multipole bin for one of the fields, where a polarized foreground, consistent with Galactic synchrotron radiation, is detected with 3{sigma} significance, the E-mode spectrum is consistent with the {Lambda}CDM model, confirming the only previous detection of the first acoustic peak. The B-mode spectrum is consistent with zero, leading to a measurement of the tensor-to-scalar ratio of r = 0.35{sup +1.06}{sub -0.87}. The combination of a new time-stream 'double-demodulation' technique, side-fed Dragonian optics, natural sky rotation, and frequent boresight rotation leads to the lowest level of systematic contamination in the B-mode power so far reported, below the level of r = 0.1.

  1. Circularly polarized microwaves for magnetic resonance study in the GHz range: application to nitrogen-vacancy in diamonds

    E-Print Network [OSTI]

    Mrozek, Mariusz; Rudnicki, Daniel S; Gawlik, Wojciech

    2015-01-01T23:59:59.000Z

    The ability to create time-dependent magnetic fields of controlled polarization is essential for many experiments with magnetic resonance. We describe a microstrip circuit that allows us to generate strong magnetic field at microwave frequencies with arbitrary adjusted polarization. The circuit performance is demonstrated by applying it to an optically detected magnetic resonance and Rabi nutation experiments in nitrogen-vacancy color centers in diamond. Thanks to high efficiency of the proposed microstrip circuit and degree of circular polarization of 85% it is possible to address the specific spin states of a diamond sample using a low power microwave generator.

  2. Selected applications of microwave radiometric techniques

    E-Print Network [OSTI]

    Jean, Buford Randall

    1971-01-01T23:59:59.000Z

    detection capability is more promising. Airborne microwave radiometer measurements were made over selected flight lines near Weslaco, Texas to deter- mine the capability of a microwave radiometer system to monitor soil moisture content. An extensive... was supported by National Aeronautics and Space Administration Grant NsG 239-62. The cooperation of the NASA Goddard Space Flight Center and Dr. Thomas Schmugge in conducting the airborne microwave radiometer mission is gratefully acknowledged. Dr. Craig L...

  3. Cloud fraction, liquid and ice water contents derived from long-term radar, lidar, and microwave radiometer data are systematically compared to models to quantify and

    E-Print Network [OSTI]

    Hogan, Robin

    Cloud fraction, liquid and ice water contents derived from long-term radar, lidar, and microwave a systematic evaluation of clouds in forecast models. Clouds and their associated microphysical processes for end users of weather forecasts, who may be interested not only in cloud cover, but in other variables

  4. advanced microwave scanning: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    on radiance) and Infrared Atmospheric Sounding Interferometer (IASI)Advanced Very High Resolution Radiometer (AVHRR Li, Jun 77 900 IEEE TRANSACTIONS ON MICROWAVE THEORY AND...

  5. IEEE MTT-S 2001 International Microwave Symposium Digest, Vol. 3 pp. 1713-1716 185 GHz Monolithic Amplifier in InGaAs/InAlAs

    E-Print Network [OSTI]

    Rodwell, Mark J. W.

    , and automotive radar. Monolithic amplifiers in this frequency range have previously been demonstrated in In in these technologies have exhibited large small signal gains. Weinreb et al [1] have reported a six-stage amplifier]. Larger ICs include 66 GHz master-slave flip flops [9] and 18 GHz delta-sigma ADCs [10]. Here, we report

  6. Stable radiometal antibody immunoconjugates

    DOE Patents [OSTI]

    Mease, R.C.; Srivastava, S.C.; Gestin, J.F.

    1994-08-02T23:59:59.000Z

    The present invention relates to new rigid chelating structures, to methods for preparing these materials, and to their use in preparing radiometal labeled immunoconjugates. These new chelates include cyclohexyl EDTA monohydride, the trans forms of cyclohexyl DTPA and TTHA, and derivatives of these cyclohexyl polyaminocarboxylate materials. No Drawings

  7. ARM - Field Campaign - Microwave Radiometer Profiler Evaluation

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa- Polarization Diversity Lidar (PDL) Campaign

  8. Ground-Based Microwave Radiometer Measurements

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.NewofGeothermal Heaton Armed Services

  9. Microwave and Millimeter-Wave Radiometric Studies of Temperature, Water Vapor and Clouds

    SciTech Connect (OSTI)

    Westwater, Edgeworth

    2011-05-06T23:59:59.000Z

    The importance of accurate measurements of column amounts of water vapor and cloud liquid has been well documented by scientists within the Atmospheric Radiation Measurement (ARM) Program. At the North Slope of Alaska (NSA), both microwave radiometers (MWR) and the MWRProfiler (MWRP), been used operationally by ARM for passive retrievals of the quantities: Precipitable Water Vapor (PWV) and Liquid Water Path (LWP). However, it has been convincingly shown that these instruments are inadequate to measure low amounts of PWV and LWP. In the case of water vapor, this is especially important during the Arctic winter, when PWV is frequently less than 2 mm. For low amounts of LWP (< 50 g/m{sup 2}), the MWR and MWRP retrievals have an accuracy that is also not acceptable. To address some of these needs, in March-April 2004, NOAA and ARM conducted the NSA Arctic Winter Radiometric Experiment - Water Vapor Intensive Operational Period at the ARM NSA/Adjacent Arctic Ocean (NSA/AAO) site. After this experiment, the radiometer group at NOAA moved to the Center for Environmental Technology (CET) of the Department of Electrical and Computer Engineering of the University of Colorado at Boulder. During this 2004 experiment, a total of 220 radiosondes were launched, and radiometric data from 22.235 to 380 GHz were obtained. Primary instruments included the ARM MWR and MWRP, a Global Positioning System (GPS), as well as the CET Ground-based Scanning Radiometer (GSR). We have analyzed data from these instruments to answer several questions of importance to ARM, including: (a) techniques for improved water vapor measurements; (b) improved calibration techniques during cloudy conditions; (c) the spectral response of radiometers to a variety of conditions: clear, liquid, ice, and mixed phase clouds; and (d) forward modeling of microwave and millimeter wave brightness temperatures from 22 to 380 GHz. Many of these results have been published in the open literature. During the third year of this contract, we participated in another ARM-sponsored experiment at the NSA during February-March 2007. This experiment is called the Radiative Heating in Underexplored Bands Campaign (RHUBC) and the GSR was operated successfully for the duration of the campaign. One of the principal goals of the experiment was to provide retrievals of water vapor during PWV amounts less than 2 mm and to compare GSR data with ARM radiometers and radiosondes. A secondary goal was to compare the radiometric response of the microwave and millimeter wavelength radiometers to water and ice clouds. In this final report, we will include the separate progress reports for each of the three years of the project and follow with a section on major accomplishments of the project.

  10. Characterization and calibration of 8-channel E-band heterodyne radiometer system for SST-1 tokamak

    SciTech Connect (OSTI)

    Siju, Varsha; Kumar, Dharmendra; Shukla, Praveena; Pathak, S. K. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India)] [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India)

    2014-05-15T23:59:59.000Z

    An 8-channel E-band heterodyne radiometer system (74–86 GHz) is designed, characterized, and calibrated to measure the radial electron temperature profile by measuring Electron Cyclotron Emission spectrum at SST-1 Tokamak. The developed radiometer has a noise equivalent temperature of 1 eV and sensitivity of 5 × 10{sup 9} V/W. In order to precisely measure the absolute value of electron temperature, a calibration measurement of the radiometer system is performed using hot-cold Dicke switch method, which confirms the system linearity.

  11. Microwave Sensors Active and David G. Long

    E-Print Network [OSTI]

    Long, David G.

    waves up through high energy gamma waves. Microwaves extend over an important part of the elec be classified as either passive (radiometers) or active (radars). Each sensor class provides unique insight instruments can be divided into two broad classes: pas- sive, known as radiometers, and active, known

  12. IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 47, NO. 8, AUGUST 1999 1457 A Planar 4.5-GHz DCDC Power Converter

    E-Print Network [OSTI]

    Popovic, Zoya

    . The need for discrete magnetic components, including inductors and isolation transformers, is the main.5-GHz DC­DC Power Converter Slavko Djuki´c, Dragan Maksimovi´c, Member, IEEE, and Zoya Popovi´c, Senior a maximum power-added efficiency of 86%, corresponding drain efficiency of 95%, and 120 mW of output power

  13. IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 48, NO. 12, DECEMBER 2000 2573 A 310-GHz GaN-Based Flip-Chip Integrated

    E-Print Network [OSTI]

    York, Robert A.

    ­10-GHz GaN-Based Flip-Chip Integrated Broad-Band Power Amplifier Jane J. Xu, Stacia Keller, Gia Parish--In this paper, we report the latest progress of a GaN-based broad-band power amplifier using AlGaN/GaN high-added efficiency was achieved when biased at 24 V, which is the highest output power for a power amplifier using GaN

  14. Observations of tropical cirrus properties in the pilot radiation observation experiment using lidar and the CSIRO ARM filter radiometer

    SciTech Connect (OSTI)

    Platt, C.M.R.; Young, S.A.; Manson, P.J.; Patterson, G.R. [CSIRO, Victoria (Australia)

    1995-04-01T23:59:59.000Z

    A narrow beam fast filter radiometer has been developed for the Atmospheric Radiation Measurement (ARM) Program. The radiometer is intended to operate alongside a lidar at ARM sites in a lidar/radiometer (LIRAD) configuration. The radiometer detects in three narrow bands at 8.62-, 10.86-, and 12.04-m central wavelengths in the atmospheric window. In addition, it has a variable field aperture that varies the radiance incident on the detector and also allows the field of view to be tailored to that of a lidar used in the LIRAD technique. The radiometer was deployed in the ARM Pilot Radiation Observation Experiment (PROBE) at Kavieng, Papua New Guinea in January-February 1993. The radiometer worked satisfactorily and appeared to be very stable. The radiometer was compared with a previous CSIRO radiometer and the improved performance of the ARM instrument was very evident. The ARM radiometer was also compared with a National Oceanic and Atmospheric Administration (NOAA) Environmental Technology Laboratories (ETL) interferometer and gave closely equivalent radiances. The LIRAD method was used at Kavieng to obtain the optical properties of cirrus clouds. Continuous observations of water vapor path obtained by the NOAA ETL microwave radiometer were employed to allow for the strong tropical water vapor absorption and emission. Cirrus cells that developed on one morning, independent of other clouds, had measured infrared emittances varying from <0.1 to 1.0.

  15. 6, 54275456, 2006 Passive microwave

    E-Print Network [OSTI]

    Boyer, Edmond

    ACPD 6, 5427­5456, 2006 Passive microwave 3-D polarization effects from rainy clouds A. Battaglia radiometers A. Battaglia 1 , C. Simmer 1 , and H. Czekala 2 1 Meteorological Institute, University of Bonn April 2006 ­ Published: 27 June 2006 Correspondence to: A. Battaglia (batta@uni-bonn.de) 5427 #12;ACPD 6

  16. Christopher RUF EXTERNAL SPONSORED RESEARCH FUNDING HISTORY 06/30/1992 to 04/30/1996; "GEOSAT Follow-On water vapor radiometer engineering support,"

    E-Print Network [OSTI]

    Ruf, Christopher

    Calibration Standard for Interferometric and Polarimetric Microwave Radiometers," EMAG Technologies, Inc., Ann Cloud Radar Studies," Dept. of Energy; $500,000 ($75,000/yr to Ruf); Co-I (PI is T. Ackermann, PSU Dept/30/2000; "Conical-Scanning Microwave Imager/Sounder Development Program," Ball Aerospace and Technology Corporation

  17. New Technique for Retrieving Liquid Water Path over Land using Satellite Microwave Observations

    SciTech Connect (OSTI)

    Deeter, M.N.; Vivekanandan, J.

    2005-03-18T23:59:59.000Z

    We present a new methodology for retrieving liquid water path over land using satellite microwave observations. As input, the technique exploits the Advanced Microwave Scanning Radiometer for earth observing plan (EOS) (AMSR-E) polarization-difference signals at 37 and 89 GHz. Regression analysis performed on model simulations indicates that over variable atmospheric and surface conditions the polarization-difference signals can be simply parameterized in terms of the surface emissivity polarization difference ({Delta}{var_epsilon}), surface temperature, liquid water path (LWP), and precipitable water vapor (PWV). The resulting polarization-difference parameterization (PDP) enables fast and direct (noniterative) retrievals of LWP with minimal requirements for ancillary data. Single- and dual-channel retrieval methods are described and demonstrated. Data gridding is used to reduce the effects of instrumental noise. The methodology is demonstrated using AMSR-E observations over the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) site during a six day period in November and December, 2003. Single- and dual-channel retrieval results mostly agree with ground-based microwave retrievals of LWP to within approximately 0.04 mm.

  18. Potential Soil Moisture Products from the Aquarius Radiometer and Scatterometer Using an Observing System Simulation Experiment

    SciTech Connect (OSTI)

    Luo, Yan [I.M. Systems Group at NOAA/NCEP/EMC; Feng, Xia [George Mason University; Houser, Paul [George Mason University; Anantharaj, Valentine G [ORNL; Fan, Xingang [Western Kentucky University, Bowling Green; De Lannoy, Gabrielle [Ghent University, Belgium; Zhan, Xiwu [NOAA/NESDIS Center for Satellite Applications and Research; Dabbiru, Lalitha [Mississippi State University (MSU)

    2013-01-01T23:59:59.000Z

    Using an observing system simulation experiment (OSSE), we investigate the potential soil moisture retrieval capability of the National Aeronautics and Space Administration (NASA) Aquarius radiometer (L-band 1.413 GHz) and scatterometer (L-band, 1.260 GHz). We estimate potential errors in soil moisture retrievals and identify the sources that could cause those errors. The OSSE system includes (i) a land surface model in the NASA Land Information System, (ii) a radiative transfer and backscatter model, (iii) a realistic orbital sampling model, and (iv) an inverse soil moisture retrieval model. We execute the OSSE over a 1000 2200 km2 region in the central United States, including the Red and Arkansas river basins. Spatial distributions of soil moisture retrieved from the radiometer and scatterometer are close to the synthetic truth. High root mean square errors (RMSEs) of radiometer retrievals are found over the heavily vegetated regions, while large RMSEs of scatterometer retrievals are scattered over the entire domain. The temporal variations of soil moisture are realistically captured over a sparely vegetated region with correlations 0.98 and 0.63, and RMSEs 1.28% and 8.23% vol/vol for radiometer and scatterometer, respectively. Over the densely vegetated region, soil moisture exhibits larger temporal variation than the truth, leading to correlation 0.70 and 0.67, respectively, and RMSEs 9.49% and 6.09% vol/vol respectively. The domain-averaged correlations and RMSEs suggest that radiometer is more accurate than scatterometer in retrieving soil moisture. The analysis also demonstrates that the accuracy of the retrieved soil moisture is affected by vegetation coverage and spatial aggregation.

  19. Remote monitoring of soil moisture using airborne microwave radiometers 

    E-Print Network [OSTI]

    Kroll, Charles Lindsey

    1973-01-01T23:59:59.000Z

    ) site G (b) site H I V-6 i IV- 7 'IV- 8 iV- I iV- 2 ! iV-3 Chickasha test site I V-4 Ground cover for Chickasha sites: site A (b) site B 62 63 64 67 68 69 71 X1 I I' I giirc I';i g| c Ground cover I or Chickashn sites: (n) site C (b... /&[&9 T (~~)~n ~/h &. r) ryder)zn 7?'(i)? (I I-IS) ff?(~~)~a r/~ year) ~n where: V = vertical polarization H = horizontal polarization j = desired received polarization, either verti- cal or horizontal In well designed antennas, the design...

  20. Wheat stress measurement with the Electrically Scanning Microwave Radiometer (ESMR)

    E-Print Network [OSTI]

    Richter, John Charles

    1980-01-01T23:59:59.000Z

    . 35 0Hz, of some natural surfaces. They found ice had an emissivity of 0. 92 while for water it was 0. 4. Yfet soil, at field capacity, had an emissivity of 0. 6 while dry soil had a value of 0. 94. The values for dry and wet soil are for smooth... winter wheat were not used. This was to insure that wheat emission made a significant contribution to the brightness temperature. A further restriction was that the wheat fields comprising the 30 percent must be continuously cropped. This removed from...

  1. ARM - Field Campaign - Long-Term Microwave Radiometer Intercomparison

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del(ANL-IN-03-032)8LigovCampaignsCLEX-5govCampaignsFall-CloudsgovCampaignsLong-Term

  2. Experimental study of a 1.5-MW, 110-GHz gyrotron oscillator

    E-Print Network [OSTI]

    Anderson, James P. (James Paul), 1972-

    2005-01-01T23:59:59.000Z

    This thesis reports the design, construction and testing of a 1.5 MW, 110 GHz gyrotron oscillator. This high power microwave tube has been proposed as the next evolutionary step for gyrotrons used to provide electron ...

  3. IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, VOL. 53, NO. 8, AUGUST 2006 1647 Multistatic Adaptive Microwave Imaging for Early

    E-Print Network [OSTI]

    Xie, Yao

    , and the backscattered energy distribution is calculated coherently. The advantages of UWB CMI include high to the microwave radiometry [8], [9], which uses radiometers to measure temperature differences between the normal

  4. Novel Cyclotron-Based Radiometal Production

    SciTech Connect (OSTI)

    DeGrado, Timothy R. [Mayo Clinic] [Mayo Clinic (United States)

    2013-10-31T23:59:59.000Z

    Accomplishments: (1) Construction of prototype solution target for radiometal production; (2) Testing of prototype target for production of following isotopes: a. Zr-89. Investigation of Zr-89 production from Y-89 nitrate solution. i. Defined problems of gas evolution and salt precipitation. ii. Solved problem of precipitation by addition of nitric acid. iii. Solved gas evolution problem with addition of backpressure regulator and constant degassing of target during irradiations. iv. Investigated effects of Y-89 nitrate concentration and beam current. v. Published abstracts at SNM and ISRS meetings; (3) Design of 2nd generation radiometal solution target. a. Included reflux chamber and smaller target volume to conserve precious target materials. b. Included aluminum for prototype and tantalum for working model. c. Included greater varicosities for improved heat transfer; and, (4) Construction of 2nd generation radiometal solution target started.

  5. Modification of the collective Thomson scattering radiometer in the search for parametric decay on TEXTOR

    SciTech Connect (OSTI)

    Nielsen, S. K.; Salewski, M.; Korsholm, S. B.; Leipold, F.; Meo, F.; Michelsen, P.; Stejner, M. [Association EURATOM - DTU, Department of Physics, Technical University of Denmark, Risoe Campus, DK-4000 Roskilde (Denmark); Bongers, W.; Moseev, D.; Westerhof, E. [FOM Institute DIFFER, Dutch Institute for Fundamental Energy Research, Association EURATOM - FOM, Nieuwegein (Netherlands); Oosterbeek, J. W. [Department of Applied Physics, Science and Technology of Nuclear Fusion, Eindhoven University of Technology, NL-5600 MB Eindhoven (Netherlands)

    2012-11-15T23:59:59.000Z

    Strong scattering of high-power millimeter waves at 140 GHz has been shown to take place in heating and current-drive experiments at TEXTOR when a tearing mode is present in the plasma. The scattering signal is at present supposed to be generated by the parametric decay instability. Here we describe the heterodyne detection system used to characterize the newly discovered signal measured at TEXTOR, and we present spectral shapes in which the signal can appear under different conditions. The radiation is collected by the receiver through a quasi-optical transmission line that is independent of the electron cyclotron resonance heating transmission line, and so the scattering geometry is variable. The signal is detected with 42 frequency channels ranging from 136 to 142 GHz. We demonstrate that the large signal does not originate from gyrotron spurious radiation. The measured signal agrees well with independent backscattering radiometer data.

  6. Millimeter-wave Radiometer for High Sensitivity Water Vapor Profiling in Arid Regions

    SciTech Connect (OSTI)

    Pazmany, Andrew

    2006-11-09T23:59:59.000Z

    Abstract - ProSensing Inc. has developed a G-band (183 GHz) water Vapor Radiometer (GVR) for long-term, unattended measurements of low concentrations of atmospheric water vapor and liquid water. Precipitable water vapor and liquid water path are estimated from zenith brightness temperatures measured from four double-sideband receiver channels, centered at 183.31 1, 3 and 7, and 14 GHz. A prototype ground-based version of the instrument was deployed at the DOE ARM program?s North Slope of Alaska site near Barrow AK in April 2005, where it collected data continuously for one year. A compact, airborne version of this instrument, packaged to operate from a standard 2-D PMS probe canister, has been tested on the ground and is scheduled for test flights in the summer of 2006. This paper presents design details, laboratory test results and examples of retrieved precipitable water vapor and liquid water path from measured brightness temperature data.

  7. Development of multichannel intermediate frequency system for electron cyclotron emission radiometer on KSTAR Tokamak

    SciTech Connect (OSTI)

    Kogi, Yuichiro; Sakoda, Takuya; Mase, Atsushi; Ito, Naoki; Yokota, Yuya [Art, Science and Technology Center for Cooperative Research, Kyushu University, Kasuga Fukuoka 816-8580 (Japan); Yamaguchi, Soichiro; Nagayama, Yoshio; Kawahata, Kazuo [National Institute for Fusion Science, Toki Gifu 509-5292 (Japan); Jeong, Seung H. [Korea Atomic Energy Research Institute, 1045 Daedeokdaero Daejeon (Korea, Republic of); Kwon, Myeun [National Fusion Research Institute, 113 Gwahangno Daejeon (Korea, Republic of)

    2008-10-15T23:59:59.000Z

    Plasma experiments on KSTAR are scheduled to start up this year (2008). We have developed an electron cyclotron emission (ECE) radiometer to measure the radial electron temperature profiles in KSTAR experiments. The radiometer system consists, briefly, of two downconversion stages, amplifiers, bandpass filter banks, and video detectors. These components are made commercially or developed in house. The system detects ECE power in the frequency range from 110 to 196 GHz, the detected signal being resolved by means of 48 frequency windows. Before installation of this system on KSTAR, we installed a part of this system on large helical device (LHD) to study the system under similar plasma conditions. In this experiment, the signal amplitude, considered to be proportional to the electron temperature, is measured. The time-dependent traces of the electron temperature measured by this radiometer are in good agreement with those provided by the LHD Michelson spectrometer. The system noise level which limits the minimum measurable temperature (converted to the electron temperature) is about 30 eV.

  8. A radiometer for stochastic gravitational waves

    E-Print Network [OSTI]

    Stefan W. Ballmer

    2005-10-20T23:59:59.000Z

    The LIGO Scientific Collaboration recently reported a new upper limit on an isotropic stochastic background of gravitational waves obtained based on the data from the 3rd LIGO science Run (S3). Now I present a new method for obtaining directional upper limits that the LIGO Scientific Collaboration intends to use for future LIGO science runs and that essentially implements a gravitational wave radiometer.

  9. Microwave-driven breakdown: from dielectric surface multipactor

    E-Print Network [OSTI]

    Shyy, Wei

    .85 GHz)Experimental Setup (2.85 GHz) HPM Load Directional Coupler Directional Coupler Rear Viewing Port HPM from Test Section Front Viewing Port HPM from Source Test Section Features ·WR284-WR650 StandardsRF Window Flashover > MW transmitted power (High Power Microwaves, HPM) Field amplitudes in excess

  10. Microwave processing of tantalum capacitor anodes

    SciTech Connect (OSTI)

    Lauf, R J; Hamby, C; Holcombe, C E [Oak Ridge National Lab., TN (United States)] [Oak Ridge National Lab., TN (United States); Vierow, W F [AVX Tantalum Corp., Biddeford, ME (United States)] [AVX Tantalum Corp., Biddeford, ME (United States)

    1992-08-01T23:59:59.000Z

    Porous tantalum anodes were sintered at temperatures from 1600 to 1900{degrees}C using a conventional high-vacuum furnace as well as both 2.45 GHz fixed-frequency and 4--8 GHz variable-frequency microwave furnaces. Various insulation and casketing techniques were used to couple the microwave power to the tantalum compacts. Several types of tantalum powder were used to assess the effect of microwave processing on sintered surface area and impurity levels. Some microwave sintered anodes have an unusual surface rippling not seen on conventionally fired parts. The rippling suggests that a microscopic arcing or plasma might have been generated. Two important effects could be exploited if this phenomenon can be controlled. First, the effective tantalum surface area could be increased, yielding higher capacitance per volume. Second, surface impurities might be cleaned away, allowing the formation of a better dielectric film during the anodization process and, ultimately, higher working voltage.

  11. Microwaves in Photochemistry and Photocatalysis Vladimir Cirkva

    E-Print Network [OSTI]

    Cirkva, Vladimir

    563 14 Microwaves in Photochemistry and Photocatalysis Vladim´ir C´irkva 14.1 Introduction photocatalysis. The energy of MW radia- tion (e.g., E = 0.98 J mol-1 at = 2.45 GHz) is considerably lower than by Wiley-VCH Verlag GmbH & Co. KGaA. #12;564 14 Microwaves in Photochemistry and Photocatalysis UV

  12. A new radiometer for earth radiation budget studies

    SciTech Connect (OSTI)

    Weber, P.G.

    1992-05-01T23:59:59.000Z

    A critical need for the US Global Change Research Program is to provide continuous, well-calibrated radiometric data for radiation balance studies. This paper describes a new, compact, relatively light-weight, adaptable radiometer which will provide both spectrally integrated measurements and data in selected spectral bands. The radiometer design is suitable for use on (small) satellites, aircraft, or Unmanned Aerospace Vehicles (UAVs). Some considerations for the implementation of this radiometer on a small satellite are given. 17 refs.

  13. MEASUREMENTS AND RETRIEVALS FROM A NEW 183-GHz WATER VAPOR RADIOMETER IN

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9November 6, In this3, BPA earned net3rdTHE

  14. active cavity radiometer: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in North America from long-term records of the advanced very high resolution radiometer Geosciences Websites Summary: Interannual changes of active fire detectability in...

  15. Low density inorganic foams fabricated using microwaves

    SciTech Connect (OSTI)

    Meek, T.T.; Blake, R.D.; Gregory, T.G.

    1985-01-01T23:59:59.000Z

    The objective of our work was to determine if high temperature foams could be made using microwave heating; and if so, to investigate some of their properties. Several foams were made and their compressive strengths, tensile strengths and densities were determined. Foams were made of glass, metal-glass, glass-fiber, metal-glass-fiber, and fly ash. The microwave source used was a Litton model 1521 microwave oven which operated at 2.45 GHz and had an output of 700 watts.

  16. The Anisotropy in the Cosmic Microwave Background At Degree Angular Scales.

    E-Print Network [OSTI]

    are 36­39.5, 39.5­43, 43­46 GHz. The six channels in each radiometer view the sky in a single­axis parabola. The FWHM beam in K a band is 1:42 \\Sigma 0:02 ffi and in Q band is 1:04 \\Sigma 0:02 ffi . After

  17. Single scattering parameters of randomly oriented snow particles at microwave frequencies

    E-Print Network [OSTI]

    Houze Jr., Robert A.

    can affect earth energy balance through the surface albedo change. Ground-based radars have been used] Millimeter-wave radiometers operating at frequencies greater than 90 GHz have been employed to estimate, 2004; Kim, 2004] because of their high sensitivity to scattering by snow in the atmosphere

  18. Broadband patterned magnetic microwave absorber

    SciTech Connect (OSTI)

    Li, Wei; Wu, Tianlong; Wang, Wei; Guan, Jianguo, E-mail: guanjg@whut.edu.cn [State Key Lab of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Zhai, Pengcheng [School of Science, Wuhan University of Technology, Wuhan 430070 (China)

    2014-07-28T23:59:59.000Z

    It is a tough task to greatly improve the working bandwidth for the traditional flat microwave absorbers because of the restriction of available material parameters. In this work, a simple patterning method is proposed to drastically broaden the absorption bandwidth of a conventional magnetic absorber. As a demonstration, an ultra-broadband microwave absorber with more than 90% absorption in the frequency range of 4–40 GHz is designed and experimentally realized, which has a thin thickness of 3.7?mm and a light weight equivalent to a 2-mm-thick flat absorber. In such a patterned absorber, the broadband strong absorption is mainly originated from the simultaneous incorporation of multiple ?/4 resonances and edge diffraction effects. This work provides a facile route to greatly extend the microwave absorption bandwidth for the currently available absorbing materials.

  19. Microfluidic Radiometal Labeling Systems for Biomolecules

    SciTech Connect (OSTI)

    Reichert, D E; Kenis, P J. A.

    2011-12-29T23:59:59.000Z

    In a typical labeling procedure with radiometals, such as Cu-64 and Ga-68; a very large (~ 100-fold) excess of the non-radioactive reactant (precursor) is used to promote rapid and efficient incorporation of the radioisotope into the PET imaging agent. In order to achieve high specific activities, careful control of reaction conditions and extensive chromatographic purifications are required in order to separate the labeled compounds from the cold precursors. Here we propose a microfluidic approach to overcome these problems, and achieve high specific activities in a more convenient, semi-automated fashion and faster time frame. Microfluidic reactors, consisting of a network of micron-sized channels (typical dimensions in the range 10 â�� 300 �¼m), filters, separation columns, electrodes and reaction loops/chambers etched onto a solid substrate, are now emerging as an extremely useful technology for the intensification and miniaturization of chemical processes. The ability to manipulate, process and analyze reagent concentrations and reaction interfaces in both space and time within the channel network of a microreactor provides the fine level of reaction control that is desirable in PET radiochemistry practice. These factors can bring radiometal labeling, specifically the preparation of radio-labeled biomolecules such as antibodies, much closer to their theoretical maximum specific activities.

  20. Mobile system for microwave removal of concrete surfaces

    DOE Patents [OSTI]

    White, Terry L. (Oak Ridge, TN); Bigelow, Timothy S. (Knoxville, TN); Schaich, Charles R. (Lenoir City, TN); Foster, Jr., Don (Knoxville, TN)

    1997-01-01T23:59:59.000Z

    A method and apparatus for the microwave removal of contaminated concrete surfaces. The apparatus comprises a housing adapted to pass over a support surface. The housing includes a waveguide for directing microwave energy to the surface at an angle maximizing absorption of microwave energy by the surface. The apparatus is further provided with a source of microwave energy operably associated with the waveguide, wherein the microwave energy has a frequency of between about 10.6 GHz and about 24 GHz and acts to remove the uppermost layer from the surface. The apparatus further includes a debris containment assembly comprising a vacuum assembly operably associated with the housing. The vacuum assembly is adapted to remove debris from the area adjacent the surface.

  1. Mobile system for microwave removal of concrete surfaces

    DOE Patents [OSTI]

    White, T.L.; Bigelow, T.S.; Schaich, C.R.; Foster, D. Jr.

    1997-06-03T23:59:59.000Z

    A method and apparatus are disclosed for the microwave removal of contaminated concrete surfaces. The apparatus comprises a housing adapted to pass over a support surface. The housing includes a waveguide for directing microwave energy to the surface at an angle maximizing absorption of microwave energy by the surface. The apparatus is further provided with a source of microwave energy operably associated with the waveguide, wherein the microwave energy has a frequency of between about 10.6 GHz and about 24 GHz and acts to remove the uppermost layer from the surface. The apparatus further includes a debris containment assembly comprising a vacuum assembly operably associated with the housing. The vacuum assembly is adapted to remove debris from the area adjacent the surface. 7 figs.

  2. Microwave detector

    DOE Patents [OSTI]

    Meldner, Heiner W. (Moss Beach, CA); Cusson, Ronald Y. (Chapel Hill, NC); Johnson, Ray M. (San Ramon, CA)

    1986-01-01T23:59:59.000Z

    A microwave detector (10) is provided for measuring the envelope shape of a microwave pulse comprised of high-frequency oscillations. A biased ferrite (26, 28) produces a magnetization field flux that links a B-dot loop (16, 20). The magnetic field of the microwave pulse participates in the formation of the magnetization field flux. High-frequency insensitive means (18, 22) are provided for measuring electric voltage or current induced in the B-dot loop. The recorded output of the detector is proportional to the time derivative of the square of the envelope shape of the microwave pulse.

  3. Microwave detector

    DOE Patents [OSTI]

    Meldner, H.W.; Cusson, R.Y.; Johnson, R.M.

    1985-02-08T23:59:59.000Z

    A microwave detector is provided for measuring the envelope shape of a microwave pulse comprised of high-frequency oscillations. A biased ferrite produces a magnetization field flux that links a B-dot loop. The magnetic field of the microwave pulse participates in the formation of the magnetization field flux. High-frequency insensitive means are provided for measuring electric voltage or current induced in the B-dot loop. The recorded output of the detector is proportional to the time derivative of the square of the envelope shape of the microwave pulse.

  4. Foregrounds and experiments below 33GHz

    E-Print Network [OSTI]

    A. W. Jones

    1999-05-07T23:59:59.000Z

    In this paper I report on the recent results obtained from the Tenerife switched beam (10 GHz to 33 GHz) experiment and Jodrell Bank 5 GHz interferometer and their predictions for foreground levels. The full data analysis and results will be presented elsewhere. It is found that free-free emission dominates above 10 GHz, whereas synchrotron emission dominates below 5 GHz.

  5. IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 45, NO. 6, JUNE 1997 963 Planar Microwave Integrated Phase-Shifter Design

    E-Print Network [OSTI]

    De Flaviis, Franco

    Microwave Integrated Phase-Shifter Design with High Purity Ferroelectric Material Franco De Flaviis, N. G a change in the dielectric constant. A phase shift of 165 was obtained at 2.4 GHz, with an insertion loss of ferroelectric materials (FEM's) in ceramic form for the realization of a phase shifter operating at 2.4 GHz

  6. ARM: Broadband Radiometer Station (BRS) broadband shortwave and longwave 1-min radiation data with Dutton correction

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Stoffel, Tom; Kay, Bev; Habte, Aron; Anderberg, Mary; Kutchenreiter, Mark

    Broadband Radiometer Station (BRS) broadband shortwave and longwave 1-min radiation data with Dutton correction

  7. GHZ ELECTRICAL PROPERTIES OF CARBON NANOTUBES ON SILICON DIOXIDE MICRO BRIDGES

    E-Print Network [OSTI]

    Tang, William C

    1 GHZ ELECTRICAL PROPERTIES OF CARBON NANOTUBES ON SILICON DIOXIDE MICRO BRIDGES SHENG F. YEN1 of an approach to reduce the high-frequency capacitive feedthrough and dielectric leakages of carbon nanotubes grown on silicon dioxide micro bridges suspended over silicon substrates. The microwave reflection

  8. All-optical signal processing at 10?GHz using a photonic crystal molecule

    SciTech Connect (OSTI)

    Combrié, Sylvain; Lehoucq, Gaëlle; Junay, Alexandra; De Rossi, Alfredo, E-mail: alfredo.derossi@thalesgroup.com [Thales Research and Technology, 1 Avenue A. Fresnel, 91767 Palaiseau (France); Malaguti, Stefania; Bellanca, Gaetano; Trillo, Stefano [Department of Engineering, Università di Ferrara, v. Saragat 1, 44122 Ferrara (Italy)] [Department of Engineering, Università di Ferrara, v. Saragat 1, 44122 Ferrara (Italy); Ménager, Loic [Thales Systèmes Aeroportés, 2 Av. Gay Lussac, 78851 Elancourt (France)] [Thales Systèmes Aeroportés, 2 Av. Gay Lussac, 78851 Elancourt (France); Peter Reithmaier, Johann [Institute of Nanostructure Technologies and Analytics, CINSaT, University of Kassel, Heinrich-Plett-Str. 40, 34132 Kassel (Germany)] [Institute of Nanostructure Technologies and Analytics, CINSaT, University of Kassel, Heinrich-Plett-Str. 40, 34132 Kassel (Germany)

    2013-11-04T23:59:59.000Z

    We report on 10?GHz operation of an all-optical gate based on an Indium Phosphide Photonic Crystal Molecule. Wavelength conversion and all-optical mixing of microwave signals are demonstrated using the 2 mW output of a mode locked diode laser. The spectral separation of the optical pump and signal is crucial in suppressing optical cross-talk.

  9. Satellite Microwave remote sensing of contrasting surface water inundation changes within the ArcticBoreal Region

    E-Print Network [OSTI]

    Montana, University of

    -atmosphere water, energy and carbon (CO2, CH4) fluxes, and potential feedbacks to climate change. Here we report fractional open water (Fw) cover from the Advanced Microwave Scanning Radiometer for EOS (AMSR-E). The AMSR ) of regions above 49°N (Brown et al., 1998). Although permafrost is widespread at high latitudes due to low

  10. Passive microwave soil moisture downscaling using evaporative fraction Olivier Merlin1

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    stations (METFLUX) and six flights of the L-band Push Broom Microwave Radiometer (PBMR). For each PBMR fraction (EF), which is the ratio of the evapotranspiration to the total energy available at the surface, especially for high soil moisture values. Those results illustrate the potential use of high

  11. Plasma Physics Challenges of MMPlasma Physics Challenges of MM--toto--THz and High Power MicrowaveTHz and High Power Microwave

    E-Print Network [OSTI]

    Solid StateSolid State Microwave Power ElectronicsMicrowave Power Electronics · Both convert kinetic Devices (Avg) Vacuum HPM (Peak) Solid State Lasers (Peak) Solid State Devices (Avg) Power(W) (Single ...BUT ... For f > 100 GHz VEDs frontier 1/f2P High power limit for Solid State 1/f 2 and HPM Frontier

  12. Deflection microwave and millimeter-wave amplifiers

    SciTech Connect (OSTI)

    Tang., C.M. [Naval Research Lab., Washington, DC (United States)] [Naval Research Lab., Washington, DC (United States); Lau, Y.Y. [Univ. of Michigan, Ann Arbor, MI (United States)] [Univ. of Michigan, Ann Arbor, MI (United States); Swyden, T.A. [FM Technologies, Inc., Fairfax, VA (United States)] [FM Technologies, Inc., Fairfax, VA (United States)

    1994-03-01T23:59:59.000Z

    A new class of microwave and millimeter-wave amplifiers, called deflectron amplifiers, which are based on the deflection of low voltage electron beams in a microstructure were analyzed. This concept may be applied in two ways: as microelectronic amplifiers or as bunched beam cathodes to power conventional amplifier configurations such as klystrodes and traveling wave tubes. Estimates for gain and efficiency are obtained from a circuit analysis. Particle codes are used to test the viability of the concept. Frequencies of operation are projected up to a few tens of GHz for microelectronic amplifiers and up to {approx}80 GHz for power amplifiers 29 refs., 5 figs.

  13. A 5 GHz LNA for a Radio-Astronomy Experiment

    E-Print Network [OSTI]

    Bergano, Miguel; Rocha, Armando; Barbosa, Domingos

    2011-01-01T23:59:59.000Z

    The paper describes the project, implementation and test of a C-band (5GHz) Low Noise Amplifier (LNA) using new low noise Pseudomorphic High Electron Mobility Transistors (pHEMTS) from Avago. The amplifier was developed to be used as a cost effective solution in a receiver chain for Galactic Emission Mapping (GEM-P) project in Portugal with the objective of finding affordable solutions not requiring strong cryogenic operation, as is the case of massive projects like the Square Kilometer Array (SKA), in Earth Sensing projects and other niches like microwave reflectometry. The particular application and amplifier requirements are first introduced. Several commercially available low noise devices were selected and the noise performance simulated. An ultra-low noise pHEMT was used for an implementation that achieved a Noise Figure of 0.6 dB with 13 dB gain at 5 GHz. The design, simulation and measured results of the prototype are presented and discussed.

  14. Multifilter Rotating Shadowband Radiometer (MFRSR) Handbook

    SciTech Connect (OSTI)

    Hodges, GB; Michalsky, JJ

    2011-02-07T23:59:59.000Z

    The visible Multifilter Rotating Shadowband Radiometer (MFRSR) is a passive instrument that measures global and diffuse components of solar irradiance at six narrowband channels and one open, or broadband, channel (Harrison et al. 1994). Direct irradiance is not a primary measurement, but is calculated using the diffuse and global measurements. To collect one data record, the MFRSR takes measurements at four different shadowband positions. The first measurement is taken with the shadowband in the nadir (home) position. The next three measurements are, in order, the first side-band, sun-blocked, and second side-band. The side-band measurements are used to correct for the portion of the sky obscured by the shadowband. The nominal wavelengths of the narrowband channels are 415, 500, 615, 673, 870, and 940 nm. From such measurements, one may infer the atmosphere's aerosol optical depth at each wavelength. In turn, these optical depths may be used to derive information about the column abundances of ozone and water vapor (Michalsky et al. 1995), as well as aerosol (Harrison and Michalsky 1994) and other atmospheric constituents.

  15. Plasma physics and related challenges of millimeter-wave-to-terahertz and high power microwave generationa...

    E-Print Network [OSTI]

    Smith, James E.

    confronting "classic" high power microwave HPM generators including long-life bright electron beam sources, high power mmw-to-THz sources are compared and contrasted to those of HPM generation, and future assume long pulse or average power, with exceptions be- tween 1 and 10 GHz for high power microwave HPM

  16. A new microwave spectroscope

    E-Print Network [OSTI]

    Salis, Andrew E.

    1951-01-01T23:59:59.000Z

    A NEW MICROWAVE SPECTROSCOPE A Dissertation By Andrew E. Sail* June 1951 Approved as to style and content by Chairman of Com ttee A NEW MICROWAVE SPECTROSCOPE A Dissertation Submitted to the Faculty of the Agricultural and Mechanical.... THEORETICAL APPROACH TO THE DESIGNING OP A MICROWAVE SPECTROSCOPE .................... 7 III. DESIGN OF THE EXPERIMENTAL MICROWAVE SPECTROSCOPE .......................... 14 Microwave Source .............................. 17 Microwave Circuit...

  17. Using indium tin oxide material to implement the imaging of microwave plasma ignition process

    SciTech Connect (OSTI)

    Wang, Qiang; Hou, Lingyun; Zhang, Guixin, E-mail: guixin@mail.tsinghua.edu.cn; Zhang, Boya; Liu, Cheng [Department of Electrical Engineering, Tsinghua University, Beijing 100084 (China); Wang, Zhi; Huang, Jian [State Key Laboratory of Automotive Safety and Energy, Tsinghua University, Beijing 100084 (China)

    2014-02-17T23:59:59.000Z

    In this paper, a method is introduced to get global observation of microwave plasma ignition process at high pressure. A microwave resonator was designed with an indium tin oxide coated glass at bottom. Microwave plasma ignition was implemented in methane and air mixture at 10 bars by a 2?ms-3?kW-2.45?GHz microwave pulse, and the high speed images of the ignition process were obtained. The images visually proved that microwave plasma ignition could lead to a multi-point ignition. The system may also be applied to obtain Schlieren images, which is commonly used to observe the development of flame kernel in an ignition process.

  18. Microwave furnace having microwave compatible dilatometer

    DOE Patents [OSTI]

    Kimrey, Jr., Harold D. (Knoxville, TN); Janney, Mark A. (Knoxville, TN); Ferber, Mattison K. (Oak Ridge, TN)

    1992-01-01T23:59:59.000Z

    An apparatus for measuring and monitoring a change in the dimension of a sample being heated by microwave energy is described. The apparatus comprises a microwave heating device for heating a sample by microwave energy, a microwave compatible dilatometer for measuring and monitoring a change in the dimension of the sample being heated by microwave energy without leaking microwaves out of the microwave heating device, and a temperature determination device for measuring and monitoring the temperature of the sample being heated by microwave energy.

  19. Microwave furnace having microwave compatible dilatometer

    DOE Patents [OSTI]

    Kimrey, H.D. Jr.; Janney, M.A.; Ferber, M.K.

    1992-03-24T23:59:59.000Z

    An apparatus for measuring and monitoring a change in the dimension of a sample being heated by microwave energy is described. The apparatus comprises a microwave heating device for heating a sample by microwave energy, a microwave compatible dilatometer for measuring and monitoring a change in the dimension of the sample being heated by microwave energy without leaking microwaves out of the microwave heating device, and a temperature determination device for measuring and monitoring the temperature of the sample being heated by microwave energy. 2 figs.

  20. Active radiometer for self-calibrated furnace temperature measurements

    DOE Patents [OSTI]

    Woskov, Paul P. (Bedford, MA); Cohn, Daniel R. (Chestnut Hill, MA); Titus, Charles H. (Newtown Square, PA); Wittle, J. Kenneth (Chester Springs, PA); Surma, Jeffrey E. (Kennewick, WA)

    1996-01-01T23:59:59.000Z

    Radiometer with a probe beam superimposed on its field-of-view for furnace temperature measurements. The radiometer includes a heterodyne millimeter/submillimeter-wave receiver including a millimeter/submillimeter-wave source for probing. The receiver is adapted to receive radiation from a surface whose temperature is to be measured. The radiation includes a surface emission portion and a surface reflection portion which includes the probe beam energy reflected from the surface. The surface emission portion is related to the surface temperature and the surface reflection portion is related to the emissivity of the surface. The simultaneous measurement of surface emissivity serves as a real time calibration of the temperature measurement.

  1. Broadband microwave imaging spectroscopy with a solardedicated array

    E-Print Network [OSTI]

    the thermal structure of the solar atmosphere, and to study energy release and particle energization the range 1-- 26.5 GHz. Keywords: Radio interferometry, spectroscopy, optical fiber, correlator 1Broad­band microwave imaging spectroscopy with a solar­dedicated array T.S. Bastian a , D.E. Gary b

  2. INTEGRATED GHz VOLTAGE CONTROLLED OSCILLATORS

    E-Print Network [OSTI]

    Kinget, Peter

    INTEGRATED GHz VOLTAGE CONTROLLED OSCILLATORS Peter Kinget Bell Labs - Lucent Technologies Murray Hill, NJ (USA) Abstract The voltage controlled oscillator (VCO) is a critical sub. We focus on the de- sign of a critical sub-block: the voltage controlled oscillator (VCO). We review

  3. Evaluation of Radiometers Deployed at the National Renewable Energy Laboratory's Solar Radiation Research Laboratory

    SciTech Connect (OSTI)

    Habte, A.; Wilcox, S.; Stoffel, T.

    2014-02-01T23:59:59.000Z

    This study analyzes the performance of various commercially available radiometers used for measuring global horizontal irradiances and direct normal irradiances. These include pyranometers, pyrheliometers, rotating shadowband radiometers, and a pyranometer with fixed internal shading and are all deployed at the National Renewable Energy Laboratory's Solar Radiation Research Laboratory. Data from 32 global horizontal irradiance and 19 direct normal irradiance radiometers are presented. The radiometers in this study were deployed for one year (from April 1, 2011, through March 31, 2012) and compared to measurements from radiometers with the lowest values of estimated measurement uncertainties for producing reference global horizontal irradiances and direct normal irradiances.

  4. A 10GHz CMOS Distributed Voltage Controlled Oscillator1 Hui Wu and Ali Hajimiri

    E-Print Network [OSTI]

    Hajimiri, Ali

    . The output of the drain line is then fed back to the input of the gate line. (It is assumed that both lines the microwave front-end and digital back-end on the same chip and provides a system-on-a-chip solution in the reverse gain mode, using the output from the idle drain load as the feedback output [5]. A 4 GHz

  5. Absolute Calibration of the Radio Astronomy Flux Density Scale at 22 to 43 GHz Using Planck

    E-Print Network [OSTI]

    Partridge, B; Perley, R A; Stevens, J; Butler, B J; Rocha, G; Walter, B; Zacchei, A

    2015-01-01T23:59:59.000Z

    The Planck mission detected thousands of extragalactic radio sources at frequencies from 28 to 857 GHz. Planck's calibration is absolute (in the sense that it is based on the satellite's annual motion around the Sun and the temperature of the cosmic microwave background), and its beams are well characterized at sub-percent levels. Thus Planck's flux density measurements of compact sources are absolute in the same sense. We have made coordinated VLA and ATCA observations of 65 strong, unresolved Planck sources in order to transfer Planck's calibration to ground-based instruments at 22, 28, and 43 GHz. The results are compared to microwave flux density scales currently based on planetary observations. Despite the scatter introduced by the variability of many of the sources, the flux density scales are determined to 1-2% accuracy. At 28 GHz, the flux density scale used by the VLA runs 3.6% +- 1.0% below Planck values; at 43 GHz, the discrepancy increases to 6.2% +- 1.4% for both ATCA and the VLA.

  6. A device for microwave sintering large ceramic articles

    DOE Patents [OSTI]

    Kimrey, H.D. Jr.

    1987-07-24T23:59:59.000Z

    A microwave sintering system is provided for uniform sintering of large and/or irregular shapes ceramic articles at microwave frequencies of at least 28 GHz in the hundreds of kilowatts power range in an untuned cavity. A 28 GHz, 200 kw gyrotron with variable power output is used as the microwave source connected to an untuned microwave cavity formed of an electrically conductive housing. The part to be sintered is placed in the cavity and supported on a removable high temperature table in a central location within the cavity. The part is surrounded by a microwave transparent bulk insulating material to reduce thermal heat loss at the part surfaces and maintain more uniform temperature. The cavity may be operated at a high vacuum to aid in preventing arcing. The system allows controlled increased heating rates of greater than 200/degree/C/min to provide rapid heating of a ceramic part to a selected sintering temperature where it is maintained by regulating the microwave power applied to the part. As a result of rapid heating, the extent on non-isothermal processes such as segregation of impurities to the grain boundaries are minimized and exaggerated grain growth is reduced, thereby strengthening the mechanical properties of the ceramic part being sintered. 1 fig.

  7. Ocean Water Vapor and Cloud Burden Trends Derived from the Topex Microwave Radiometer

    E-Print Network [OSTI]

    Ruf, Christopher

    algorithm is a log-linear regression algorithm with coefficients that are stratified by wind speed and water. TMR OBSERVATIONS The TMR flew in a 10-day non-sun-synchronous exact repeat orbit with an inclination

  8. Determination of an Amazon Hot Reference Target for the On-Orbit Calibration of Microwave Radiometers

    E-Print Network [OSTI]

    Ruf, Christopher

    , University of Michigan, Ann Arbor, Michigan (Manuscript received 12 May 2004, in final form 14 January 2005-surface winds, ocean surface roughness, sea ice concentration, land surface vegetation and soil mois- ture, Corresponding author address: Chris Ruf, University of Michi- gan, 2455 Hayward St., Ann Arbor, MI 48109-2143. E

  9. Validation of Satellite-Derived Liquid Water Paths Using ARM SGP Microwave Radiometers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps toValidatingCloud Properties

  10. Improved Retrievals of Temperature and Water Vapor Profiles Using a Twelve-Channel Microwave Radiometer

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh School footballHydrogenIT |HotImpactControl

  11. Quantitative Analysis of Spectral Impacts on Silicon Photodiode Radiometers: Preprint

    SciTech Connect (OSTI)

    Myers, D. R.

    2011-04-01T23:59:59.000Z

    Inexpensive broadband pyranometers with silicon photodiode detectors have a non-uniform spectral response over the spectral range of 300-1100 nm. The response region includes only about 70% to 75% of the total energy in the terrestrial solar spectral distribution from 300 nm to 4000 nm. The solar spectrum constantly changes with solar position and atmospheric conditions. Relative spectral distributions of diffuse hemispherical irradiance sky radiation and total global hemispherical irradiance are drastically different. This analysis convolves a typical photodiode response with SMARTS 2.9.5 spectral model spectra for different sites and atmospheric conditions. Differences in solar component spectra lead to differences on the order of 2% in global hemispherical and 5% or more in diffuse hemispherical irradiances from silicon radiometers. The result is that errors of more than 7% can occur in the computation of direct normal irradiance from global hemispherical irradiance and diffuse hemispherical irradiance using these radiometers.

  12. ARM Multi-Filter Rotating Shadowband Radiometer (MFRSR): irradiances

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Hodges, Gary

    The multifilter rotating shadowband radiometer (MFRSR) takes spectral measurements of direct normal, diffuse horizontal and total horizontal solar irradiances. These measurements are at nominal wavelengths of 415, 500, 615, 673, 870, and 940 nm. The measurements are made at a user-specified time interval, usually about one minute or less. The sampling rate for the Atmospheric Radiation Measurement (ARM) Climate Research Facility MFRSRs is 20 seconds. From such measurements, one may infer the atmosphere's optical depth at the wavelengths mentioned above. In turn, these optical depths may be used to derive information about the column abundances of ozone and water vapor (Michalsky et al. 1995), as well as aerosol (Michalsky et al. 1994) and other atmospheric constituents. A silicon detector is also part of the MFRSR. This detector provides a measure of the broadband direct normal, diffuse horizontal and total horizontal solar irradiances. A MFRSR head that is mounted to look vertically downward can measure upwelling spectral irradiances. In the ARM system, this instrument is called a multifilter radiometer (MFR). At the Southern Great Plains (SGP) there are two MFRs; one mounted at the 10-m height and the other at 25 m. At the North Slope of Alaska (NSA) sites, the MFRs are mounted at 10 m. MFRSR heads are also used to measure normal incidence radiation by mounting on a solar tracking device. These are referred to as normal incidence multi-filter radiometers (NIMFRs) and are located at the SGP and NSA sites. Another specialized use for the MFRSR is the narrow field of view (NFOV) instrument located at SGP. The NFOV is a ground-based radiometer (MFRSR head) that looks straight up.

  13. The multi-filter rotating shadowband radiometer (MFRSR) - precision infrared radiometer (PIR) platform in Fairbanks: Scientific objectives

    SciTech Connect (OSTI)

    Stamnes, K.; Leontieva, E. [Univ. of Alaska, Fairbanks (United States)

    1996-04-01T23:59:59.000Z

    The multi-filter rotating shadowband radiometer (MFRSR) and precision infrared radiometer (PIR) have been employed at the Geophysical Institute in Fairbanks to check their performance under arctic conditions. Drawing on the experience of the previous measurements in the Arctic, the PIR was equipped with a ventilator to prevent frost and moisture build-up. We adopted the Solar Infrared Observing Sytem (SIROS) concept from the Southern Great Plains Cloud and Radiation Testbed (CART) to allow implementation of the same data processing software for a set of radiation and meteorological instruments. To validate the level of performance of the whole SIROS prior to its incorporation into the North Slope of Alaska (NSA) Cloud and Radiation Testbed Site instrumental suite for flux radiatin measurements, the comparison between measurements and model predictions will be undertaken to assess the MFRSR-PIR Arctic data quality.

  14. Microwave to Optical Link Using an Optical Microresonator

    E-Print Network [OSTI]

    Jost, J D; Lecaplain, C; Brasch, V; Pfeiffer, M H P; Kippenberg, T J

    2014-01-01T23:59:59.000Z

    The ability to phase coherently link optical to radio frequencies with femtosecond modelocked lasers has enabled counting cycles of light and is the basis of optical clocks, absolute frequency synthesis, tests of fundamental physics, and improved spectroscopy. Using an optical microresonator frequency comb to establish a coherent link promises to greatly extend optical frequency synthesis and measurements to areas requiring compact form factor, on chip integration and repetition rates in the microwave regime, including coherent telecommunications, astrophysical spectrometer calibration or microwave photonics. Here we demonstrate for the first time a microwave to optical link using a microresonator. Using a temporal dissipative single soliton state in an ultra high Q crystalline microresonator an optical frequency comb is generated that is self-referenced, allowing to phase coherently link a 190 THZ optical carrier directly to a 14 GHz microwave frequency. Our work demonstrates that precision optical frequency...

  15. Dielectric and microwave attenuation properties of graphene nanoplatelet–epoxy composites

    SciTech Connect (OSTI)

    Wang, Zhou; Luo, Jia; Zhao, Guang–Lin, E-mail: guang-lin-zhao@subr.edu [Department of Physics, Southern University and A and M college, Baton Rouge, LA 70813 (United States)] [Department of Physics, Southern University and A and M college, Baton Rouge, LA 70813 (United States)

    2014-01-15T23:59:59.000Z

    Graphene nanoplatelet (GNP)–epoxy composites were fabricated for the investigation of the dielectric permittivity and microwave absorption in a frequency range from 8 to 20 GHz. The intrinsically conductive GNP particles and polarized interfacial centers in the composites contribute to the microwave absorption. A minimum reflection loss of ?14.5 dB at 18.9 GHz is observed for the GNP–epoxy composites with 15 wt. % GNP loading, which is mainly attributed to electric conductivity and the charge multipoles at the polarized interfaces in the GNP–epoxy composites.

  16. An Experimental Study of Waveguide Coupled Microwave Heating with Conventional Multicusp Negative Ion Source

    E-Print Network [OSTI]

    Komppula, J; Koivisto, H; Laulainen, J; Tarvainen, O

    2015-01-01T23:59:59.000Z

    Negative ion production with conventional multicusp plasma chambers utilizing 2.45 GHz microwave heating is demonstrated. The experimental results were obtained with the multicusp plasma chambers and extraction systems of the RFdriven RADIS ion source and the filament driven arc discharge ion source LIISA. A waveguide microwave coupling system, which is almost similar to the one used with the SILHI ion source, was used. The results demonstrate that at least one third of negative ion beam obtained with inductive RF-coupling (RADIS) or arc discharge (LIISA) can be achieved with 1 kW of 2.45 GHz microwave power in CW mode without any modification of the plasma chamber. The co-extracted electron to H^- ratio and the optimum pressure range were observed to be similar for both heating methods. The behaviour of the plasma implies that the energy transfer from the microwaves to the plasma electrons is mainly an off-resonance process.

  17. FIVE-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE OBSERVATIONS: SOURCE CATALOG

    SciTech Connect (OSTI)

    Wright, E. L.; Chen, X. [UCLA Physics and Astronomy, P.O. Box 951547, Los Angeles, CA 90095-1547 (United States); Odegard, N.; Hill, R. S.; Weiland, J. L. [Adnet Systems, Inc., 7515 Mission Dr., Suite A100, Lanham, MD 20706 (United States); Bennett, C. L.; Gold, B.; Larson, D. [Department of Physics and Astronomy, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218-2686 (United States); Hinshaw, G.; Wollack, E.; Kogut, A. [Code 665, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Jarosik, N.; Page, L.; Dunkley, J. [Department of Physics, Jadwin Hall, Princeton University, Princeton, NJ 08544-0708 (United States); Komatsu, E. [Department of Astronomy, University of Texas, Austin, 2511 Speedway, RLM 15.306, Austin, TX 78712 (United States); Nolta, M. R. [Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St. George St., Toronto, ON M5S 3H8 (Canada); Spergel, D. N. [Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544-1001 (United States); Halpern, M. [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1Z1 (Canada); Limon, M. [Columbia Astrophysics Laboratory, 550 W. 120th St., Mail Code 5247, New York, NY 10027-6902 (United States); Meyer, S. S. [Departments of Astrophysics and Physics, KICP and EFI, University of Chicago, Chicago, IL 60637 (United States)], E-mail: wright@astro.ucla.edu (and others)

    2009-02-15T23:59:59.000Z

    We present the list of point sources found in the Wilkinson Microwave Anisotropy Probe (WMAP) five-year maps. The technique used in the first-year and three-year analyses now finds 390 point sources, and the five-year source catalog is complete for regions of the sky away from the Galactic plane to a 2 Jy limit, with SNR >4.7 in all bands in the least covered parts of the sky. The noise at high frequencies is still mainly radiometer noise, but at low frequencies the cosmic microwave background (CMB) anisotropy is the largest uncertainty. A separate search of CMB-free V-W maps finds 99 sources of which all but one can be identified with known radio sources. The sources seen by WMAP are not strongly polarized. Many of the WMAP sources show significant variability from year to year, with more than a 2:1 range between the minimum and maximum fluxes.

  18. InP HBT Digital ICs and MMICs in the 140-220 GHz band

    E-Print Network [OSTI]

    Rodwell, Mark J. W.

    As Schottky mixer diodes many THz RC and transit time frequencies 10-nm to 100-nm electron drift devices / 485 GHz fmax ~4 V breakdown 150 GHz static dividers 178 GHz amplifiers SiGe HBT: 130 nm emitter 300 GHz f / 350 GHz fmax 96 GHz static dividers 77 GHz amplifiers 150 GHz push-push VCO- 75 GHz

  19. Correlation of globe thermometer response and a YSI radiometer response

    E-Print Network [OSTI]

    Franknecht, Robert Howard

    1979-01-01T23:59:59.000Z

    in the steel 57 in i; try. -' The radian+ heat coiinponon* ivas a major part o' Lhls heat s Lice . = ex'oosrir'e. iclschl mca. sul d the radio. i+ hc t txt Ej xsi Ly with " "ell ov! prir;. ?, s inst ament-:: e*t erin' (v. l' " odcl 653 Radiometer... This investigation developed two regression equations relating measurements of radiant heat, air velocity, and dry bulb temperature to black globe temperatures. The radiant heat energy was controlled over the range of 200 to 2000 Joules/cm sec, as measured by a...

  20. Design evaluation of a ground based radiometer system

    E-Print Network [OSTI]

    McClellan, Wallace Roy

    1977-01-01T23:59:59.000Z

    Radiometer Total Power Receiver . . . . . . . . 57 IV-2 X-Band RF Head. . . . . . . . . . . . . . . . . 59 IV-3 Insertion Loss Test Setup . . . . . . . . . . . 69 IV-4 Hewlett-Packard 8410S-200 Network Analyzer S ystem. ~ s t ~ ~ ~ ~ 1 ~ ~ ~ ~ 0 ~ ~ ~ 72... of the soil and surface parameters, i. e. , moisture ' C Data Set PD 2 Tape 065 7/28/75 Time-1108 Pond File Freq Polar Angle Average Maximum Minimum A. T. A. T. A. T. St'd Dev'n 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46...

  1. Improvement of microwave feeding on a large bore ECRIS with permanent magnets by using coaxial semi-dipole antenna

    SciTech Connect (OSTI)

    Kurisu, Yosuke; Sakamoto, Naoki; Kiriyama, Ryutaro; Takenaka, Tomoya; Nozaki, Dai; Yano, Keisuke; Sato, Fuminobu; Kato, Yushi; Iida, Toshiyuki [Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka Univ. 2-1 Yamadaoka, Suita, Osaka, 565-0871 (Japan)

    2012-11-06T23:59:59.000Z

    We are constructing a tandem type electron cyclotron resonance (ECR) ion source (ECRIS). The first stage of this ECRIS has a large-bore with cylindrically comb-shaped permanent magnets. 2.45GHz and 11-13GHz microwaves can be supplied individually and simultaneously to the plasma chamber. For 2.45GHz, a coaxial semi-dipole antenna is used to feed the microwaves. In previous experiments, there were two problems encountered when running the 2.45GHz microwaves. High incident power was necessary to keep ECR discharge at low operating pressure because of high reflected microwave power. The surface of a support insulator between the inner and the outer electrodes of coaxial semi-dipole antenna was easily metalized by sputtering of the metal wall inside the chamber. The purpose of this study was to solve these problems. Performing several simulation experiments supports the hypothesis that the position of the support insulator is significant for microwave power efficiency. The end result was the ability to sustain ECR discharges at extremely low incident microwave power, several tens of watts, by optimized matching of the position and shape of the insulator.

  2. ECE RADIOMETER UPGRADE ON THE DIII-D TOKAMAK

    SciTech Connect (OSTI)

    AUSTIN, ME; LOHR, J

    2002-08-01T23:59:59.000Z

    OAK A271 ECE RADIOMETER UPGRADE ON THE DIII-D TOKAMAK. The electron cyclotron emission (ECE) heterodyne radiometer diagnostic on DIII-D has been upgraded with the addition of eight channels for a total of 40. The new, higher frequency channels allow measurements of electron temperature into the magnetic axis in discharges at maximum field, 2.15 T. The complete set now extends over the full usable range of second harmonic emission frequencies at 2.0 T covering radii from the outer edge inward to the location of third harmonic overlap on the high field side. Full coverage permits the measurement of heat pulses and magnetohydrodynamic (MHD) fluctuations on both sides of the magnetic axis. In addition, the symmetric measurements are used to fix the location of the magnetic axis in tokamak magnetic equilibrium reconstructions. Also, the new higher frequency channels have been used to determine central T{sub e} with good time resolution in low field, high density discharges using third harmonic ECE in the optically gray and optically thick regimes.

  3. Detection of 6.7 GHz methanol absorption towards hot corinos

    E-Print Network [OSTI]

    J. D. Pandian; S. Leurini; K. M. Menten; A. Belloche; P. F. Goldsmith

    2008-08-14T23:59:59.000Z

    Methanol masers at 6.7 GHz have been found exclusively towards high-mass star forming regions. Recently, some Class 0 protostars have been found to display conditions similar to what are found in hot cores that are associated with massive star formation. These hot corino sources have densities, gas temperatures, and methanol abundances that are adequate for exciting strong 6.7 GHz maser emission. This raises the question of whether 6.7 GHz methanol masers can be found in both hot corinos and massive star forming regions, and if not, whether thermal methanol emission can be detected. We searched for the 6.7 GHz methanol line towards five hot corino sources in the Perseus region using the Arecibo radio telescope. To constrain the excitation conditions of methanol, we observed thermal submillimeter lines of methanol in the NGC1333-IRAS 4 region with the APEX telescope. We did not detect 6.7 GHz emission in any of the sources, but found absorption against the cosmic microwave background in NGC1333-IRAS 4A and NGC1333-IRAS 4B. Using a large velocity gradient analysis, we modeled the excitation of methanol over a wide range of physical parameters, and verify that the 6.7 GHz line is indeed strongly anti-inverted for densities lower than 10^6 cm^-3. We used the submillimeter observations of methanol to verify the predictions of our model for IRAS 4A by comparison with other CH3OH transitions. Our results indicate that the methanol observations from the APEX and Arecibo telescopes are consistent with dense (n ~ 10^6 cm^-3), cold (T ~ 15-30 K) gas. The lack of maser emission in hot corinos and low-mass protostellar objects in general may be due to densities that are much higher than the quenching density in the region where the radiation field is conducive to maser pumping.

  4. High brightness microwave lamp

    DOE Patents [OSTI]

    Kirkpatrick, Douglas A.; Dolan, James T.; MacLennan, Donald A.; Turner, Brian P.; Simpson, James E.

    2003-09-09T23:59:59.000Z

    An electrodeless microwave discharge lamp includes a source of microwave energy, a microwave cavity, a structure configured to transmit the microwave energy from the source to the microwave cavity, a bulb disposed within the microwave cavity, the bulb including a discharge forming fill which emits light when excited by the microwave energy, and a reflector disposed within the microwave cavity, wherein the reflector defines a reflective cavity which encompasses the bulb within its volume and has an inside surface area which is sufficiently less than an inside surface area of the microwave cavity. A portion of the reflector may define a light emitting aperture which extends from a position closely spaced to the bulb to a light transmissive end of the microwave cavity. Preferably, at least a portion of the reflector is spaced from a wall of the microwave cavity. The lamp may be substantially sealed from environmental contamination. The cavity may include a dielectric material is a sufficient amount to require a reduction in the size of the cavity to support the desired resonant mode.

  5. Ferrite-ferroelectric layered structures for electrically and magnetically tunable microwave resonators

    E-Print Network [OSTI]

    Demokritov, S.O.

    Ferrite-ferroelectric layered structures for electrically and magnetically tunable microwave It is demonstrated experimentally that a layered structure consisting of ferrite and ferroelectric thin films can constant , and a bias magnetic field to the ferrite layer. The resonator having central frequency f0 5 GHz

  6. Microwave hemorrhagic stroke detector

    DOE Patents [OSTI]

    Haddad, Waleed S. (Dublin, CA); Trebes, James E. (Livermore, CA)

    2002-01-01T23:59:59.000Z

    The microwave hemorrhagic stroke detector includes a low power pulsed microwave transmitter with a broad-band antenna for producing a directional beam of microwaves, an index of refraction matching cap placed over the patients head, and an array of broad-band microwave receivers with collection antennae. The system of microwave transmitter and receivers are scanned around, and can also be positioned up and down the axis of the patients head. The microwave hemorrhagic stroke detector is a completely non-invasive device designed to detect and localize blood pooling and clots or to measure blood flow within the head or body. The device is based on low power pulsed microwave technology combined with specialized antennas and tomographic methods. The system can be used for rapid, non-invasive detection of blood pooling such as occurs with hemorrhagic stroke in human or animal patients as well as for the detection of hemorrhage within a patient's body.

  7. Microwave hemorrhagic stroke detector

    DOE Patents [OSTI]

    Haddad, Waleed S. (Dublin, CA); Trebes, James E. (Livermore, CA)

    2007-06-05T23:59:59.000Z

    The microwave hemorrhagic stroke detector includes a low power pulsed microwave transmitter with a broad-band antenna for producing a directional beam of microwaves, an index of refraction matching cap placed over the patients head, and an array of broad-band microwave receivers with collection antennae. The system of microwave transmitter and receivers are scanned around, and can also be positioned up and down the axis of the patients head. The microwave hemorrhagic stroke detector is a completely non-invasive device designed to detect and localize blood pooling and clots or to measure blood flow within the head or body. The device is based on low power pulsed microwave technology combined with specialized antennas and tomographic methods. The system can be used for rapid, non-invasive detection of blood pooling such as occurs with hemorrhagic stoke in human or animal patients as well as for the detection of hemorrhage within a patient's body.

  8. Microwave Dielectric Heating of Drops in Microfluidic Devices

    E-Print Network [OSTI]

    David Issadore; Katherine J. Humphry; Keith A. Brown; Lori Sandberg; David Weitz; Robert M. Westervelt

    2009-01-09T23:59:59.000Z

    We present a technique to locally and rapidly heat water drops in microfluidic devices with microwave dielectric heating. Water absorbs microwave power more efficiently than polymers, glass, and oils due to its permanent molecular dipole moment that has a large dielectric loss at GHz frequencies. The relevant heat capacity of the system is a single thermally isolated picoliter drop of water and this enables very fast thermal cycling. We demonstrate microwave dielectric heating in a microfluidic device that integrates a flow-focusing drop maker, drop splitters, and metal electrodes to locally deliver microwave power from an inexpensive, commercially available 3.0 GHz source and amplifier. The temperature of the drops is measured by observing the temperature dependent fluorescence intensity of cadmium selenide nanocrystals suspended in the water drops. We demonstrate characteristic heating times as short as 15 ms to steady-state temperatures as large as 30 degrees C above the base temperature of the microfluidic device. Many common biological and chemical applications require rapid and local control of temperature, such as PCR amplification of DNA, and can benefit from this new technique.

  9. The Planck/LFI Radiometer Electronics Box Assembly

    E-Print Network [OSTI]

    Herreros, J M; Rebolo, R; Chulani, H; Rubino-Martin, J A; Hildebrandt, S R; Bersanelli, M; Butler, R C; Miccolis, M; Pena, A; Pereira, M; Torrero, F; Franceschet, C; Lopez, M; Alcala, C; 10.1088/1748-0221/4/12/T12008

    2010-01-01T23:59:59.000Z

    The Radiometer Electronics Box Assembly (REBA) is the control and data processing on board computer of the Low Frequency Instrument (LFI) of the Planck mission (ESA). The REBA was designed and built incorporating state of the art processors, communication interfaces and real time operating system software in order to meet the scientific performance of the LFI. We present a technical summary of the REBA, including a physical, functional, electrical, mechanical and thermal description. Aspects of the design and development, the assembly, the integration and the verification of the equipment are provided. A brief description of the LFI on board software is given including the Low-Level Software and the main functionalities and architecture of the Application Software. The compressor module, which has been developed as an independent product, later integrated in the application, is also described in this paper. Two identical engineering models EM and AVM, the engineering qualification model EQM, the flight model ...

  10. Global, exact cosmic microwave background data analysis using Gibbs sampling

    SciTech Connect (OSTI)

    Wandelt, Benjamin D. [Department of Physics, UIUC, 1110 W Green Street, Urbana, Illinois 61801 (United States); Department of Astronomy, UIUC, 1002 W Green Street, Urbana, Illinois 61801 (United States); Larson, David L.; Lakshminarayanan, Arun [Department of Physics, UIUC, 1110 W Green Street, Urbana, Illinois 61801 (United States)

    2004-10-15T23:59:59.000Z

    We describe an efficient and exact method that enables global Bayesian analysis of cosmic microwave background (CMB) data. The method reveals the joint posterior density (or likelihood for flat priors) of the power spectrum C{sub l} and the CMB signal. Foregrounds and instrumental parameters can be simultaneously inferred from the data. The method allows the specification of a wide range of foreground priors. We explicitly show how to propagate the non-Gaussian dependency structure of the C{sub l} posterior through to the posterior density of the parameters. If desired, the analysis can be coupled to theoretical (cosmological) priors and can yield the posterior density of cosmological parameter estimates directly from the time-ordered data. The method does not hinge on special assumptions about the survey geometry or noise properties, etc., It is based on a Monte Carlo approach and hence parallelizes trivially. No trace or determinant evaluations are necessary. The feasibility of this approach rests on the ability to solve the systems of linear equations which arise. These are of the same size and computational complexity as the map-making equations. We describe a preconditioned conjugate gradient technique that solves this problem and demonstrate in a numerical example that the computational time required for each Monte Carlo sample scales as n{sub p}{sup 3/2} with the number of pixels n{sub p}. We use our method to analyze the data from the Differential Microwave Radiometer on the Cosmic Background Explorer and explore the non-Gaussian joint posterior density of the C{sub l} from the Differential Microwave Radiometer on the Cosmic Background Explorer in several projections.

  11. A Comparison of Direct Heating During Radiofrequency and Microwave Ablation in Ex Vivo Liver

    SciTech Connect (OSTI)

    Andreano, Anita; Brace, Christopher L., E-mail: clbrace@wisc.edu [University of Wisconsin, Department of Radiology (United States)

    2013-04-15T23:59:59.000Z

    This study was designed to determine the magnitude and spatial distribution of temperature elevations when using 480 kHz RF and 2.45 GHz microwave energy in ex vivo liver models. A total of 60 heating cycles (20 s at 90 W) were performed in normal, RF-ablated, and microwave-ablated liver tissues (n = 10 RF and n = 10 microwave in each tissue type). Heating cycles were performed using a 480-kHz generator and 3-cm cooled-tip electrode (RF) or a 2.45-GHz generator and 14-gauge monopole (microwave) and were designed to isolate direct heating from each energy type. Tissue temperatures were measured by using fiberoptic thermosensors 5, 10, and 15 mm radially from the ablation applicator at the depth of maximal heating. Power delivered, sensor location, heating rates, and maximal temperatures were compared using mixed effects regression models. No significant differences were noted in mean power delivered or thermosensor locations between RF and microwave heating groups (P > 0.05). Microwaves produced significantly more rapid heating than RF at 5, 10, and 15 mm in normal tissue (3.0 vs. 0.73, 0.85 vs. 0.21, and 0.17 vs. 0.09 Degree-Sign C/s; P < 0.05); and at 5 and 10 mm in ablated tissues (2.3 {+-} 1.4 vs. 0.7 {+-} 0.3, 0.5 {+-} 0.3 vs. 0.2 {+-} 0 Degree-Sign C/s, P < 0.05). The radial depth of heating was {approx}5 mm greater for microwaves than RF. Direct heating obtained with 2.45-GHz microwave energy using a single needle-like applicator is faster and covers a larger volume of tissue than 480-kHz RF energy.

  12. The 6.7-GHz and 25-GHz methanol masers in OMC-1

    E-Print Network [OSTI]

    M. A. Voronkov; A. M. Sobolev; S. P. Ellingsen; A. B. Ostrovskii

    2005-07-02T23:59:59.000Z

    The Australia Telescope Compact Array (ATCA) has been used to search for methanol maser emission at 6.7 GHz towards OMC-1. Two features peaking at 7.2 km/s and -1.1 km/s have been detected. The former has at least two components close in both velocity and position. It is located south-east of the Orion Kleinmann-Low (Orion-KL) nebula in the region of outflow traced by the 25-GHz methanol masers and the 95-GHz methanol emission. It is shown by modelling that in contrast to the widespread opinion that simultaneous masing of methanol transitions of different classes is impossible there are conditions for which simultaneous masing of the class II transition at 6.7-GHz and some class I transitions (e.g. the series at 25 GHz) is possible. A relevant example is provided, in which the pumping occurs via the first torsionally excited state and is driven by radiation of the dust intermixed with the gas in the cloud. In this regime the dust temperature is significantly lower (T is about 60 K) than in the case of bright 6.7-GHz masers (T>150 K). The narrow spectral feature at -1.1 km/s has a brightness temperature greater than about 1400 K, which suggests that it is probably a maser. It emanates from the Orion South region and is probably associated with the approaching part of outflow seen in CO. The 25-GHz maser associated with OMC-1 was observed quasi-simultaneously with the 6.7-GHz observations. No 25-GHz emission associated with the -1.1 km/s 6.7 GHz feature towards Orion South was detected.

  13. Sea surface temperature for climate from the along-track scanning radiometers 

    E-Print Network [OSTI]

    Embury, Owen

    2014-06-30T23:59:59.000Z

    This thesis describes the construction of a sea surface temperature (SST) dataset from Along-Track Scanning Radiometer (ATSR) observations suitable for climate applications. The algorithms presented here are now used at ...

  14. Evaluating Solar Resource Data Obtained from Multiple Radiometers Deployed at the National Renewable Energy Laboratory: Preprint

    SciTech Connect (OSTI)

    Habte, A.; Sengupta, M.; Andreas, A.; Wilcox, S.; Stoffel, T.

    2014-09-01T23:59:59.000Z

    Solar radiation resource measurements from radiometers are used to predict and evaluate the performance of photovoltaic and concentrating solar power systems, validate satellite-based models for estimating solar resources, and advance research in solar forecasting and climate change. This study analyzes the performance of various commercially available radiometers used for measuring global horizontal irradiances (GHI) and direct normal irradiances (DNI). These include pyranometers, pyrheliometers, rotating shadowband irradiometers, and a pyranometer with a shading ring deployed at the National Renewable Energy Laboratory's Solar Radiation Research Laboratory (SRRL). The radiometers in this study were deployed for one year (from April 1, 2011, through March 31, 2012) and compared to measurements from radiometers with the lowest values of estimated measurement uncertainties for producing reference GHI and DNI.

  15. Two-frequency heating technique at the 18 GHz electron cyclotron resonance ion source of the National Institute of Radiological Sciences

    E-Print Network [OSTI]

    Biri, S; Muramatsu, M; Drentje, A G; Rácz, R; Yano, K; Kato, Y; Sasaki, N; Takasugi, W

    2015-01-01T23:59:59.000Z

    The two-frequency heating technique was studied to increase the beam intensities of highly charged ions provided by the high-voltage extraction configuration (HEC) ion source at the National Institute of Radiological Sciences (NIRS). The observed dependences on microwave power and frequency suggested that this technique improved plasma stability but it required precise frequency tuning and more microwave power than was available before 2013. Recently, a new, high-power (1200 W) wide bandwidth (17.1-18.5 GHz) travelling-wave-tube amplifier (TWTA) was installed. After some single tests with klystron and TWT amplifiers the simultaneous injection of the two microwaves has been successfully realized. The dependence of highly charged ions (HCI) currents on the superposed microwave power was studied by changing only the output power of one of the two amplifiers, alternatively. While operating the klystron on its fixed 18.0 GHz, the frequency of the TWTA was swept within its full limits (17.1-18.5 GHz), and the effec...

  16. Two-gigawatt burst-mode operation of the intense microwave prototype (IMP) free-electron laser (FEL) for the microwave tokamak experiment (MTX)

    SciTech Connect (OSTI)

    Felker, B.; Allen, S.; Bell, H. [and others

    1993-10-06T23:59:59.000Z

    The MTX explored the plasma heating effects of 140 GHz microwaves from both Gyrotrons and from the IMP FEL wiggler. The Gyrotron was long pulse length (0.5 seconds maximum) and the FEL produced short-pulse length, high-peak power, single and burst modes of 140 GHZ microwaves. Full-power operations of the IMP FEL wiggler were commenced in April of 1992 and continued into October of 1992. The Experimental Test Accelerator H (ETA-II) provided a 50-nanosecond, 6-MeV, 2--3 kAmp electron beam that was introduced co-linear into the IMP FEL with a 140 GHz Gyrotron master oscillator (MO). The FEL was able to amplify the MO signal from approximately 7 kW to peaks consistently in the range of 1--2 GW. This microwave pulse was transmitted into the MTX and allowed the exploration of the linear and non-linear effects of short pulse, intense power in the MTX plasma. Single pulses were used to explore and gain operating experience in the parameter space of the IMP FEL, and finally evaluate transmission and absorption in the MTX. Single-pulse operations were repeatable. After the MTX was shut down burst-mode operations were successful at 2 kHz. This paper will describe the IMP FEL, Microwave Transmission System to MTX, the diagnostics used for calorimetric measurements, and the operations of the entire Microwave system. A discussion of correlated and uncorrelated errors that affect FEL performance will be made Linear and non-linear absorption data of the microwaves in the MTX plasma will be presented.

  17. Design of a 250 GHz gyrotron amplifier

    E-Print Network [OSTI]

    Nanni, Emilio A. (Emilio Alessandro)

    2010-01-01T23:59:59.000Z

    A design is presented of a 250 GHz, 1 kW gyrotron traveling wave tube (gyro-TWT) amplifier with gain exceeding 50 dB. Calculations show that the amplifier will operate at 32 kV, 1 A with a saturated gain of 60 dB, an output ...

  18. A novel wideband 140 GHz gyrotron amplifier

    E-Print Network [OSTI]

    Joye, Colin D., 1980-

    2008-01-01T23:59:59.000Z

    The theory, design and experimental results of a wideband 140 GHz, 1 kW pulsed gyro-traveling wave amplifier are presented. The gyro- TWA operates in the HE(0,6) mode of a novel cylindrical confocal waveguide using a ...

  19. Compact microwave ion source for industrial applications

    SciTech Connect (OSTI)

    Cho, Yong-Sub; Kim, Dae-Il; Kim, Han-Sung; Seol, Kyung-Tae; Kwon, Hyeok-Jung; Hong, In-Seok [Proton Engineering Frontier Project, Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of)

    2012-02-15T23:59:59.000Z

    A 2.45 GHz microwave ion source for ion implanters has many good properties for industrial application, such as easy maintenance and long lifetime, and it should be compact for budget and space. But, it has a dc current supply for the solenoid and a rf generator for plasma generation. Usually, they are located on high voltage platform because they are electrically connected with beam extraction power supply. Using permanent magnet solenoid and multi-layer dc break, high voltage deck and high voltage isolation transformer can be eliminated, and the dose rate on targets can be controlled by pulse duty control with semiconductor high voltage switch. Because the beam optics does not change, beam transfer components, such as focusing elements and beam shutter, can be eliminated. It has shown the good performances in budget and space for industrial applications of ion beams.

  20. IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 50, NO. 10, OCTOBER 2002 2305 A Reduced-Size Silicon Micromachined

    E-Print Network [OSTI]

    Papapolymerou, Ioannis "John"

    communication systems, the need for high-performance, low-cost, low-power, and small-size RF/microwave circuits, IEEE, and John Papapolymerou, Member, IEEE Abstract--This paper depicts the progress toward a novel. Digital Object Identifier 10.1109/TMTT.2002.803428. around 200 MHz­1.5 GHz ( ), but their fabrication

  1. Evaluation of Radiometers in Full-Time Use at the National Renewable Energy Laboratory Solar Radiation Research Laboratory

    SciTech Connect (OSTI)

    Wilcox, S. M.; Myers, D. R.

    2008-12-01T23:59:59.000Z

    This report describes the evaluation of the relative performance of the complement of solar radiometers deployed at the National Renewable Energy Laboratory (NREL) Solar Radiation Research Laboratory (SRRL).

  2. Ultra-low phase noise all-optical microwave generation setup based on commercial devices

    E-Print Network [OSTI]

    Didier, A; Grop, S; Dubois, B; Bigler, E; Rubiola, E; Lacroûte, C; Kersalé, Y

    2015-01-01T23:59:59.000Z

    In this paper, we present a very simple design based on commercial devices for the all-optical generation of ultra-low phase noise microwave signals. A commercial, fibered femtosecond laser is locked to a laser that is stabilized to a commercial ULE Fabry-Perot cavity. The 10 GHz microwave signal extracted from the femtosecond laser output exhibits a single sideband phase noise $\\mathcal{L}(f)=-104 \\ \\mathrm{dBc}/\\mathrm{Hz}$ at 1 Hz Fourier frequency, at the level of the best value obtained with such "microwave photonics" laboratory experiments \\cite{Fortier2011}. Close-to-the-carrier ultra-low phase noise microwave signals will now be available in laboratories outside the frequency metrology field, opening up new possibilities in various domains.

  3. Microwave thawing apparatus and method

    DOE Patents [OSTI]

    Fathi, Zakaryae; Lauf, Robert J.; McMillan, April D.

    2004-06-01T23:59:59.000Z

    An apparatus for thawing a frozen material includes: a microwave energy source; a microwave applicator which defines a cavity for applying microwave energy from the microwave source to a material to be thawed; and a shielded region which is shielded from the microwave source, the shielded region in fluid communication with the cavity so that thawed material may flow from the cavity into the shielded region.

  4. Microwave coupler and method

    DOE Patents [OSTI]

    Holcombe, C.E.

    1984-11-29T23:59:59.000Z

    The present invention is directed to a microwave coupler for enhancing the heating or metallurgical treatment of materials within a cold-wall, rapidly heated cavity as provided by a microwave furnace. The coupling material of the present invention is an alpha-rhombohedral-boron-derivative-structure material such as boron carbide or boron silicide which can be appropriately positioned as a susceptor within the furnace to heat other material or be in powder particulate form so that composites and structures of boron carbide such as cutting tools, grinding wheels and the like can be rapidly and efficiently formed within microwave furnaces.

  5. Fabrication of optoelectronic microwave linear and ring resonators on a gallium arsenide substrate

    E-Print Network [OSTI]

    Yeh, Chun-Liang

    1993-01-01T23:59:59.000Z

    for the degree of MASTER OF SCIENCE August 1993 Major Subject: Electrical Engineering FABRICATION OF OPTOELECTRONIC MICROWAVE LINEAR AND RING RESONATORS ON A GALLIUM ARSENIDE SUBSTRATE A Thesis by CHUN-LIANG YEH Approved as to style and content by: Mark... and the first modes at 4. 87, 4. 89, 4. 91 GHz have been designed, simulated, and fabricated on a GaAs substrate. A microstrip ring resonator with 3/4 pm coupling gaps and the first mode at 3. 456 GHz also has been fabricated on GaAs. A reliable high yield...

  6. Fabrication of optoelectronic microwave linear and ring resonators on a gallium arsenide substrate 

    E-Print Network [OSTI]

    Yeh, Chun-Liang

    1993-01-01T23:59:59.000Z

    the frequency ~, = urn' +amoco) have been observed. In the third part of the optical tests, the degenerate parametric amplification of an optical signal RF modulated at the first mode of the resonator with a microwave pumping LO at second mode... for the ring resonator. 77 46 Mixing Test Setup. 79 47 The sum signal IF, for the linear resonator with 10 prn coupling gap. The RF signal is at 4. 875 GHz and the I, O signal is at 4. 750 GHz, where the IF, signal (users = ans + uiqo) is detected at 9. 624...

  7. A 915 MHz/2. 45 GHz ECR plasma source for large area ion beam and plasma processing

    SciTech Connect (OSTI)

    Asmussen, J.; Hopwood, J.; Sze, F.C. (Department of Electrical Engineering, Michigan State University, East Lansing, Michigan 48824-1226 (US))

    1990-01-01T23:59:59.000Z

    The technology for producing uniform, high density (10{sup 11}--10{sup 12}/cm{sup 3}) microwave discharges over cross sections of 50 cm{sup 2} is well established. The present challenge is to extend the high density, and electrodeless benefits of microwave discharges to produce uniform densities over an area of 300--700 cm{sup 2}. Such discharges have important applications for 6 to 8-in. single wafer processing and as large surface, broad beam, high current density ion sources. The design principles for scaling the 18 cm diam MPDR ECR cavity applicator technology to 38--47 cm diam are reviewed. Microwave discharges with diameters of 20--30 cm can be created when these applicators are excited with either 2.45 GHz or 915 MHz. The design and construction of a prototype cavity applicator with a 20 cm diam discharge is described. The discharge is enclosed with a 12-pole multicusp static magnetic field produced by 2-in. by 2-in. by 1-in. rare-earth magnets. Each magnet has a pole face field strength of 3 kG. The experimental test of this plasma source in argon gas excited with 2.45 GHz energy is reviewed.

  8. Intermediate frequency band digitized high dynamic range radiometer system for plasma diagnostics and real-time Tokamak control

    SciTech Connect (OSTI)

    Bongers, W. A.; Beveren, V. van; Westerhof, E.; Goede, A. P. H.; Krijger, B.; Berg, M. A. van den; Graswinckel, M. F.; Schueller, F. C. [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Trilateral Euregio Cluster, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Thoen, D. J. [Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft (Netherlands); Nuij, P. J. W. M. [Eindhoven University of Technology, Control Systems Technology Group, and Applied Physics Department, PO Box 513, NL-5600 MB Eindhoven (Netherlands); Baar, M. R. de; Donne, A. J. H.; Hennen, B. A. [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Trilateral Euregio Cluster, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Eindhoven University of Technology, Control Systems Technology Group, and Applied Physics Department, PO Box 513, NL-5600 MB Eindhoven (Netherlands); Kantor, M. [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Trilateral Euregio Cluster, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Forschungszentrum Juelich GMBH, Institute of Energy and Climate research, Plasma Physics, Association EURATOM-FZJ, Trilateral Euregio Cluster, 52425 Juelich (Germany); Ioffe Institute, RAS, Saint-Petersburg, 195256 (Russian Federation)

    2011-06-15T23:59:59.000Z

    An intermediate frequency (IF) band digitizing radiometer system in the 100-200 GHz frequency range has been developed for Tokamak diagnostics and control, and other fields of research which require a high flexibility in frequency resolution combined with a large bandwidth and the retrieval of the full wave information of the mm-wave signals under investigation. The system is based on directly digitizing the IF band after down conversion. The enabling technology consists of a fast multi-giga sample analog to digital converter that has recently become available. Field programmable gate arrays (FPGA) are implemented to accomplish versatile real-time data analysis. A prototype system has been developed and tested and its performance has been compared with conventional electron cyclotron emission (ECE) spectrometer systems. On the TEXTOR Tokamak a proof of principle shows that ECE, together with high power injected and scattered radiation, becomes amenable to measurement by this device. In particular, its capability to measure the phase of coherent signals in the spectrum offers important advantages in diagnostics and control. One case developed in detail employs the FPGA in real-time fast Fourier transform (FFT) and additional signal processing. The major benefit of such a FFT-based system is the real-time trade-off that can be made between frequency and time resolution. For ECE diagnostics this corresponds to a flexible spatial resolution in the plasma, with potential application in smart sensing of plasma instabilities such as the neoclassical tearing mode (NTM) and sawtooth instabilities. The flexible resolution would allow for the measurement of the full mode content of plasma instabilities contained within the system bandwidth.

  9. The Air Microwave Yield (AMY) experiment - A laboratory measurement of the microwave emission from extensive air showers

    E-Print Network [OSTI]

    K. Louedec; J. Alvarez-Muñiz; M. Blanco; M. Bohácová; B. Buonomo; G. Cataldi; M. R. Coluccia; P. Creti; I. De Mitri; C. Di Giulio; P. Facal San Luis; L. Foggetta; R. Gaïor; D. Garcia-Fernandez; M. Iarlori; S. Le Coz; A. Letessier-Selvon; I. C. Mari?; D. Martello; G. Mazzitelli; M. Monasor; L. Perrone; R. Pesce; S. Petrera; P. Privitera; V. Rizi; G. Rodriguez Fernandez; F. Salamida; G. Salina; M. Settimo; P. Valente; J. R. Vazquez; V. Verzi; C. Williams

    2013-10-17T23:59:59.000Z

    The AMY experiment aims to measure the microwave bremsstrahlung radiation (MBR) emitted by air-showers secondary electrons accelerating in collisions with neutral molecules of the atmosphere. The measurements are performed using a beam of 510 MeV electrons at the Beam Test Facility (BTF) of Frascati INFN National Laboratories. The goal of the AMY experiment is to measure in laboratory conditions the yield and the spectrum of the GHz emission in the frequency range between 1 and 20 GHz. The final purpose is to characterise the process to be used in a next generation detectors of ultra-high energy cosmic rays. A description of the experimental setup and the first results are presented.

  10. High-Power Microwave Switch Employing Electron Beam Triggering

    SciTech Connect (OSTI)

    Jay L. Hirshfield

    2012-09-19T23:59:59.000Z

    A high-power active microwave pulse compressor is described that modulates the quality factor Q of the energy storage cavity by a new means involving mode conversion controlled by a triggered electron-beam discharge through a switch cavity. The electron beam is emitted from a diamond-coated molybdenum cathode. This report describes the principle of operation, the design of the switch, the configuration used for the test, and the experimental results. The pulse compressor produced output pulses with 140 - Ã?Â?165 MW peak power, power gain of 16 - 20, and pulse duration of 16 - 20 ns at a frequency of 11.43 GHz.

  11. High power microwave generator

    DOE Patents [OSTI]

    Ekdahl, C.A.

    1983-12-29T23:59:59.000Z

    A microwave generator efficiently converts the energy of an intense relativistic electron beam (REB) into a high-power microwave emission using the Smith-Purcell effect which is related to Cerenkov radiation. Feedback for efficient beam bunching and high gain is obtained by placing a cylindrical Smith-Purcell transmission grating on the axis of a toroidal resonator. High efficiency results from the use of a thin cold annular highly-magnetized REB that is closely coupled to the resonant structure.

  12. SEVENTH HARMONIC 20 GHz CO-GENERATOR

    SciTech Connect (OSTI)

    Hirshfield, Jay L

    2014-04-08T23:59:59.000Z

    To satisfy the need for multi-MW rf sources in frequency ranges where commercial sources do not exist, a study was undertaken on a class of devices based on gyro-harmonic frequency multiplication. This mechanism relies upon adding energy in gyrating motion to a linear electron beam that traverses a rotating-mode TE111-mode drive cavity in a dc magnetic field. The beam then drifts along the magnetic field into a second cavity, operating in the TEn11-mode tuned to the nth harmonic of the drive cavity. Studies of this configuration have been carried out for 2 < n < 7. Results are given for multi-MW, efficient operation of a 7th harmonic device operating at 20 GHz, and a 2nd harmonic device operating at 22.4 GHz.

  13. Production of negative hydrogen and deuterium ions in microwave-driven ion sources.

    SciTech Connect (OSTI)

    Spence, D.

    1998-09-11T23:59:59.000Z

    The authors report progress they have made in the production of negative hydrogen and deuterium atomic ions in magnetically-confined microwave-driven (2.45 GHz) ion sources. The influence of source surface material, microwave power, source gas pressure and magnetic field configuration on the resulting ion current is discussed. Results strongly suggest that, at least in the source, vibrationally excited molecular hydrogen, the precursor to atomic negative ion production, is produced via a surface mechanism suggested by Hall et al. rather than via a gas phase reaction as is generally believed to be the case in most ion sources.

  14. 1/f noise and other systematic effects in the Planck-LFI radiometers

    E-Print Network [OSTI]

    Michael Seiffert; Aniello Mennella; Carlo Burigana; Nazzareno Mandolesi; Marco Bersanelli; Peter Meinhold; Phil Lubin

    2002-06-06T23:59:59.000Z

    We use an analytic approach to study the susceptibility of the Planck Low Frequency Instrument radiometers to various systematic effects. We examine the effects of fluctuations in amplifier gain, in amplifier noise temperature and in the reference load temperature. We also study the effect of imperfect gain modulation, non-ideal matching of radiometer parameters, imperfect isolation in the two legs of the radiometer and back-end 1/f noise. We find that with proper gain modulation 1/f gain fluctuations are suppressed, leaving fluctuations in amplifier noise temperature as the main source of 1/f noise. We estimate that with a gain modulation factor within +- 1% of its ideal value the overall 1/f knee frequency will be relatively small (< 0.1 Hz).

  15. Microwaves and particle accelerators: a fundamental link

    SciTech Connect (OSTI)

    Chattopadhyay, Swapan [Universities of Lancaster, Liverpool and Manchester and Cockcroft Institute, Cheshire (United Kingdom)

    2011-07-01T23:59:59.000Z

    John Cockcroft's splitting of the atom and Ernest Lawrence's invention of the cyclotron in the first half of the twentieth century ushered in the grand era of ever higher energy particle accelerators to probe deeper into matter. It also forged a link, bonding scientific discovery with technological innovation that continues today in the twenty first century. The development of radar and high power vacuum electronics, especially microwave power tubes like the magnetrons and the klystrons in the pre-second world war era, was instrumental in the rapid development of circular and linear charged particle accelerators in the second half of the twentieth century. We had harnessed the powerful microwave radio-frequency sources from few tens of MHz to up to 90 GHz spanning L-band to W-band frequencies. Simultaneously in the second half of the twentieth century, lasers began to offer very first opportunities of controlling charged particles at smaller resolutions on the scale of wavelengths of visible light. We also witnessed in this period the emergence of the photon and neutron sciences driven by accelerators built-by-design producing tailored and ultra-bright pulses of bright photons and neutrons to probe structure and function of matter from aggregate to individual molecular and atomic scales in unexplored territories in material and life sciences. As we enter the twenty first century, the race for ever higher energies, brightness and luminosity to probe atto-metric and atto-second domains of the ultra-small structures and ultra-fast processes continues. These developments depend crucially on yet further advancements in the production and control of high power and high frequency microwaves and light sources, often intricately coupled in their operation to the high energy beams themselves. We give a glimpse of the recent developments and innovations in the electromagnetic production and control of charged particle beams in the service of science and society. (author)

  16. On the detection of point sources in Planck LFI 70 GHz CMB maps based on cleaned K-map

    E-Print Network [OSTI]

    Khachatryan, H G; Poghosyan, E; Yegoryan, G

    2015-01-01T23:59:59.000Z

    We use the Planck LFI 70GHz data to further probe point source detection technique in the sky maps of the cosmic microwave background (CMB) radiation. The method developed by Tegmark et al. for foreground reduced maps and the Kolmogorov parameter as the descriptor are adopted for the analysis of Planck satellite CMB temperature data. Most of the detected points coincide with point sources already revealed by other methods. However, we have also found 9 source candidates for which still no counterparts are known.

  17. VLBI Observations of the Galactic Center Source Sgr A* at 86 GHz and 215 GHz

    E-Print Network [OSTI]

    T. P. Krichbaum; A. Witzel; J. A. Zensus

    1998-12-02T23:59:59.000Z

    We summarize previous VLBI observations of Sgr A* at millimeter wavelengths and present new results from VLBI observations at 86 and at 215 GHz. At 86 GHz the measured closure phase is close to zero, consistent with a point-like or symmetric structure of 190 +/- 30 micro-arcsec size. At 215 GHz we have detected Sgr A* with a signal-to-noise ratio of 6. This yields a tentative size estimate of 50 < theta < 190 micro-arcsec, which is larger than the scattering size of 20 micro-arcsec at this frequency. The intrinsic size of Sgr A* thus appears to be a few up to a few ten Schwarzschild radii.

  18. Microwave and Radio Frequency Workshop

    Broader source: Energy.gov [DOE]

    At the Microwave and Radio Frequency Workshop (held in Long Beach, CA, on July 25, 2012), academic and industry experts discussed the existing and emerging electrotechnologies – such as microwave ...

  19. Controllable microwave three-wave mixing via a single three-level superconducting quantum circuit

    E-Print Network [OSTI]

    Yu-xi Liu; Hui-Chen Sun; Z. H. Peng; Adam Miranowicz; J. S. Tsai; Franco Nori

    2014-12-21T23:59:59.000Z

    Three-wave mixing in second-order nonlinear optical processes cannot occur in atomic systems due to the electric-dipole selection rules. In contrast, we demonstrate that second-order nonlinear processes can occur in a superconducting quantum circuit (i.e., a superconducting artificial atom) when the inversion symmetry of the potential energy is broken by simply changing the applied magnetic flux. In particular, we show that difference- and sum-frequencies (and second harmonics) can be generated in the microwave regime in a controllable manner by using a single three-level superconducting flux quantum circuit (SFQC). For our proposed parameters, the frequency tunability of this circuit can be achieved in the range of about 17 GHz for the sum-frequency generation, and around 42 GHz (or 26 GHz) for the difference-frequency generation. Our proposal provides a simple method to generate second-order nonlinear processes within current experimental parameters of SFQCs.

  20. HURRICANE IMAGING RADIOMETER WIND SPEED AND RAIN RATE RETRIEVAL: [PART-1] DEVELOPMENT OF AN IMPROVED OCEAN

    E-Print Network [OSTI]

    Ruf, Christopher

    HURRICANE IMAGING RADIOMETER WIND SPEED AND RAIN RATE RETRIEVAL: [PART-1] DEVELOPMENT U.S.A * selnimri@mail.ucf.edu 2 NOAA/AOML/Hurricane Research Division, Miami, Florida, USA 3 Space model has been developed to support the analysis and design of the new airborne Hurricane Imaging

  1. THE HURRICANE IMAGING RADIOMETER WIDE SWATH SIMULATION AND WIND SPEED RETRIEVALS

    E-Print Network [OSTI]

    Ruf, Christopher

    THE HURRICANE IMAGING RADIOMETER WIDE SWATH SIMULATION AND WIND SPEED RETRIEVALS Ruba A. Amarin1 Space Flight Center, Huntsville, Alabama 4 NOAA/AOML/Hurricane Research Division, Miami, Florida, USA ABSTRACT The knowledge of peak winds in hurricanes is critical to classification of hurricane intensity

  2. Multi-Filter Rotating Shadowband Radiometers Mentor Report and Baseline Surface Radiation Network Submission Status

    SciTech Connect (OSTI)

    Hodges, G.

    2005-03-18T23:59:59.000Z

    There are currently twenty-four Multi-Filter Rotating Shadowband Radiometers (MFRSR) operating within Atmospheric Radiation Measurement (ARM). Eighteen are located within the Southern Great Plains (SGP) region, there is one at each of the North Slope of Alaska (NSA) and Tropical Western Pacific (TWP) sites, and one is part of the instrumentation of the ARM Mobile Facility. At this time there are four sites, all extended facilities within the SGP, that are equipped for a MFRSR but do not have one due to instrument failure and a lack of spare instruments. In addition to the MFRSRs, there are three other MFRSR derived instruments that ARM operates. They are the Multi-Filter Radiometer (MFR), the Normal Incidence Multi-Filter Radiometer (NIMFR) and the Narrow Field of View (NFOV) radiometer. All are essentially just the head of a MFRSR used in innovative ways. The MFR is mounted on a tower and pointed at the surface. At the SGP Central Facility there is one at ten meters and one at twenty-five meters. The NSA has a MFR at each station, both at the ten meter level. ARM operates three NIMFRs; one is at the SGP Central Facility and one at each of the NSA stations. There are two NFOVs, both at the SGP Central Facility. One is a single channel (870) and the other utilizes two channels (673 and 870).

  3. High Cooperativity Cavity QED with Magnons at Microwave Frequencies

    E-Print Network [OSTI]

    Maxim Goryachev; Warrick G. Farr; Daniel L. Creedon; Yaohui Fan; Mikhail Kostylev; Michael E. Tobar

    2014-10-16T23:59:59.000Z

    Using a sub-millimetre sized YIG (Yttrium Iron Garnet) sphere mounted in a magnetic field-focusing cavity, we demonstrate an ultra-high cooperativity of $10^5$ between magnon and photon modes at millikelvin temperatures and microwave frequencies. The cavity is designed to act as a magnetic dipole by using a novel multiple-post approach, effectively focusing the cavity magnetic field within the YIG crystal with a filling factor of 3%. Coupling strength (normal-mode splitting) of 2 GHz, (equivalent to 76 cavity linewidths or $0.3$ Hz per spin), is achieved for a bright cavity mode that constitutes about 10% of the photon energy and shows that ultra-strong coupling is possible in spin systems at microwave frequencies. With straight forward optimisations we demonstrate that with that this system has the potential to reach cooperativities of $10^7$, corresponding to a normal mode splitting of 5.2 GHz and a coupling per spin approaching 1 Hz. We also observe a three-mode strong coupling regime between a dark cavity mode and a magnon mode doublet pair, where the photon-magnon and magnon-magnon couplings (normal-mode splittings) are 143 MHz and 12.5 MHz respectively, with HWHM bandwidth of about 0.5 MHz.

  4. Floating data acquisition system for microwave calorimeter measurements on MTX

    SciTech Connect (OSTI)

    Sewall, N.R.; Meassick, S. (Lawrence Livermore National Lab., CA (USA))

    1989-09-13T23:59:59.000Z

    A microwave calorimeter has been designed for making 140-GHz absorption measurements on the MTX. Measurement of the intensity and spatial distribution of the FEL-generated microwave beam on the inner wall will indicate the absorption characteristics of the plasma when heated with a 140 GHz FEL pulse. The calorimeter works by monitoring changes of temperature in silicon carbide tiles located on the inner wall of the tokamak. Thermistors are used to measure the temperature of each tile. The tiles are located inside the tokamak about 1 cm outside of the limiter radius at machine potential. The success of this measurement depends on our ability to float the data acquisition system near machine potential and isolate it from the rest of the vault ground system. Our data acquisition system has 48 channels of thermistor signal conditioning, a multiplexer and digitizer section, a serial data formatter, and a fiber-optic transmitter to send the data out. Additionally, we bring timing signals to the interface through optical fibers to tell it when to begin measurement, while maintaining isolation. The receiver is an HP 200 series computer with a serial data interface; the computer provides storage and local display for the shot temperature profile. Additionally, the computer provides temporary storage of the data until it can be passed to a shared resource management system for archiving. 2 refs., 6 figs.

  5. A 5364-GHz SiGe Up-Conversion Mixer with 4-GHz IF Bandwidth

    E-Print Network [OSTI]

    Choi, Woo-Young

    ), Germany wchoi@yonsei.ac.kr Abstract -- A Gilbert-cell direct up-conversion mixer is realized for 57­64-GHz mixers is important for the overall system performance of direct-conversion transmitters. In particular-to-RF isolation is necessary due to in- band LO leakage in direct-conversion transmitters. In this paper

  6. A global 86 GHz VLBI survey

    E-Print Network [OSTI]

    S. Lee; A. P. Lobanov; T. P. Krichbaum; A. Witzel; J. A. Zensus; M. Bremer; A. Greve; M. Grewing

    2007-09-27T23:59:59.000Z

    We present results from a large global VLBI(Very Long Baseline Interferometry) survey of compact radio sources at 86 GHz which started in October 2001. The main goal of the survey is to increase the total number of objects accessible for future 3mm-VLBI imaging by factors of 3-5. The survey data reach the baseline sensitivity of 0.1 Jy, and image sensitivity of better than 10 mJy/beam. To date, a total of 127 compact radio sources have been observed. The observations have yielded images for 109 sources, and only 6 sources have not been detected. Flux densities and sizes of core and jet components of all detected sources have been measured using Gaussian model fitting. From these measurements, brightness temperatures have been estimated, taking into account resolution limits of the data. Here, we compare the brightness temperatures of the cores and secondary jet components with similar estimates obtained from surveys at longer wavelengths (e.g. 15 GHz). This approach can be used to study questions related to mechanisms of initial jet acceleration (accelerating or decelerating sub-pc jets?) and jet composition (electron-positron or electron-proton plasma?).

  7. Geophysical parameter estimation with a passive microwave spectrometer at 54 / 118 / 183 / 425 GHz

    E-Print Network [OSTI]

    Leslie, Robert Vincent, 1972-

    2004-01-01T23:59:59.000Z

    (cont.) model of a convective cell is presented that provides a physical basis for this relationship.

  8. A 145-GHz Interferometer for Measuring the Anisotropy of the Cosmic Microwave

    E-Print Network [OSTI]

    the observing campaign. Based on radiometric hot/cold-load tests, the SIS-mixer-based receivers are found. An ill-placed static shock that put an $8000 D-band frequency tripler out of commission was deemed

  9. Variable frequency microwave furnace system

    DOE Patents [OSTI]

    Bible, Don W. (Clinton, TN); Lauf, Robert J. (Oak Ridge, TN)

    1994-01-01T23:59:59.000Z

    A variable frequency microwave furnace system (10) designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity (34) for testing or other selected applications. The variable frequency microwave furnace system (10) includes a microwave signal generator (12) or microwave voltage-controlled oscillator (14) for generating a low-power microwave signal for input to the microwave furnace. A first amplifier (18) may be provided to amplify the magnitude of the signal output from the microwave signal generator (12) or the microwave voltage-controlled oscillator (14). A second amplifier (20) is provided for processing the signal output by the first amplifier (18). The second amplifier (20) outputs the microwave signal input to the furnace cavity (34). In the preferred embodiment, the second amplifier (20) is a traveling-wave tube (TWT). A power supply (22) is provided for operation of the second amplifier (20). A directional coupler (24) is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

  10. Variable frequency microwave furnace system

    DOE Patents [OSTI]

    Bible, D.W.; Lauf, R.J.

    1994-06-14T23:59:59.000Z

    A variable frequency microwave furnace system designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity for testing or other selected applications. The variable frequency microwave furnace system includes a microwave signal generator or microwave voltage-controlled oscillator for generating a low-power microwave signal for input to the microwave furnace. A first amplifier may be provided to amplify the magnitude of the signal output from the microwave signal generator or the microwave voltage-controlled oscillator. A second amplifier is provided for processing the signal output by the first amplifier. The second amplifier outputs the microwave signal input to the furnace cavity. In the preferred embodiment, the second amplifier is a traveling-wave tube (TWT). A power supply is provided for operation of the second amplifier. A directional coupler is provided for detecting the direction of a signal and further directing the signal depending on the detected direction. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load. 5 figs.

  11. Local microwave background radiation

    E-Print Network [OSTI]

    Domingos Soares

    2014-11-13T23:59:59.000Z

    An inquiry on a possible local origin for the Microwave Background Radiation is made. Thermal MBR photons are contained in a system called {\\it magnetic bottle} which is due to Earth magnetic field and solar wind particles, mostly electrons. Observational tests are anticipated.

  12. Highly conducting SrMoO{sub 3} thin films for microwave applications

    SciTech Connect (OSTI)

    Radetinac, Aldin, E-mail: aldin@oxide.tu-darmstadt.de; Mani, Arzhang; Ziegler, Jürgen; Alff, Lambert; Komissinskiy, Philipp, E-mail: komissinskiy@oxide.tu-darmstadt.de [Institute of Materials Science, TU Darmstadt, Alarich-Weiss-Str. 2, 64287 Darmstadt (Germany); Melnyk, Sergiy; Nikfalazar, Mohammad; Zheng, Yuliang; Jakoby, Rolf [Institute for Microwave Engineering and Photonics, TU Darmstadt, Merckstraße 25, 64283 Darmstadt (Germany)

    2014-09-15T23:59:59.000Z

    We have measured the microwave resistance of highly conducting perovskite oxide SrMoO{sub 3} thin film coplanar waveguides. The epitaxial SrMoO{sub 3} thin films were grown by pulsed laser deposition and showed low mosaicity and smooth surfaces with a root mean square roughness below 0.3?nm. Layer-by-layer growth could be achieved for film thicknesses up to 400?nm as monitored by reflection high-energy electron diffraction and confirmed by X-ray diffraction. We obtained a constant microwave resistivity of 29???·cm between 0.1 and 20?GHz by refining the frequency dependence of the transmission coefficients. Our result shows that SrMoO{sub 3} is a viable candidate as a highly conducting electrode material for all-oxide microwave electronic devices.

  13. The microwave electro-thermal (MET) thruster: A new technology for satellite propulsion and attitude control

    SciTech Connect (OSTI)

    Brandenburg, J.E. [Principle Research Scientist, Research Support Instruments, Washington Operations, 4325-B Forbes Boulevard, Lanham, Maryland 20706 (United States); Micci, M.M. [Assoc. Professor of Aerospace Eng., Propulsion Engineering Research Center, Department of Aerospace Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

    1996-03-01T23:59:59.000Z

    This paper discusses the current research status of the MET (Microwave Electro-Thermal) thruster. In the MET thruster, an electrodeless, vortex stabilized, plasma is produced in a microwave resonator cavity for the purpose of heating gaseous fuel to produce a high temperature rocket exhaust for space propulsion. The higher specific impulse (momentum transfer per unit weight) of these heated gases offers advantages over traditional chemical rockets in terms of reduced fuel mass. In MET devices, dense plasmas have been produced in various possible fuel gases, nitrogen, hydrogen, and ammonia, using 600 to 2200 Watts of microwave power at a frequency of 2.45 GHz. Ammonia has been found to give a specific impulse of 550 sec. It has been found that the plasma is a 98{percent} absorber of microwave power leading to negligible reflection of power back to the microwave source and making the cavity operate at low {ital Q}. Taking advantage of this effect, it has been found that a very compact MET thruster design could be operated, with the magnetron microwave source and resonator cavity joined in one unit. The MET can run at a variety of power levels and use many fuels, including H{sub 2}O. {copyright} {ital 1996 American Institute of Physics.}

  14. FUSING MICROWAVE RADAR AND MICROWAVE-INDUCED THERMOACOUSTICS FOR BREAST CANCER DETECTION

    E-Print Network [OSTI]

    FUSING MICROWAVE RADAR AND MICROWAVE-INDUCED THERMOACOUSTICS FOR BREAST CANCER DETECTION Evgeny in the microwave range. Microwave-radar and microwave-induced thermoacoustic methods both struggle when-induced thermoacoustic (MIT) methods measure and process the acoustic signals induced by differential microwave heating

  15. 0.5 -1.0 GHZ-3 1.25-1.75GHZ

    E-Print Network [OSTI]

    . NOTES ALFA MONITOR ALFA 6A ALFA "7A" PWR SPLITTER FIBER RECEIVER RACK 5 Ortel 10450 .01-6 GHz 1,2,...11d -20 -20 -20 -20 GPIB READ- OUT -10 HP4412 PWR HEAD -10 HP4412 PWR HEAD FROM POL B IF AMP (RACK 6) DUAL CHANNEL POWER METER #1 HP E4419A RACK 5 LEFT HAND PWR METER TRANSFER (REVERSING) SWITCH: EXAMPLE: if2 "if2

  16. Experimental test of a microwave ion beam source in oxygen

    SciTech Connect (OSTI)

    Asmussen, J.; Dahimene, M.

    1987-01-01T23:59:59.000Z

    Recent experiments have demonstrated a microwave (2.45 GHz) plasma disk ion source operating with inert gases both with and without an applied static magnetic field. Earlier results were reported using a preliminary, multicusp static magnetic field configuration produced by alternating pole, small, --2.5 kG rare earth magnets surrounding the microwave discharge zone. This electrodeless ion source has been rebuilt incorporating several improvements and has been experimentally tested with different discharge diffusion lengths. The improvements include removing the rare earth magnets from the inside of the microwave cavity and embedding them in the cavity walls. The placement and strength of the magnets allows electron cyclotron resonant surfaces (--875 G) to lie entirely within the discharge zone. Discharges with different diffusion lengths were created by varying the thickness of the disk-shaped discharge zone. The experimental performance with and without a static magnetic field is discussed at the low flow rates of 2--10 sccm and using a 2.5 cm diam double grid set. Experimental test results are compared to similar ion beam sources in oxygen that employ a dc discharge. The expected lifetime, startup, and shutdown problems and maintenance are also reviewed.

  17. A precise narrow-beam filter infrared radiometer and its use with lidar in the ARM Program

    SciTech Connect (OSTI)

    Platt, C.M.R.

    1992-05-01T23:59:59.000Z

    The first six months of the grant (December 1991--May 1992) have been taken up with the design and specification for the new narrow-beam radiometer. The radiometer will be built and tested at the Division of Atmospheric Research over the next three months. Improved algorithms for obtaining cloud extinction have also been developed. It is proposed during 1993 to use the radiometer in conjunction with a new CSIRO 3-wavelength lidar in the ARM PROBE experiment at Kavieng, New Guinea, which is a test mission under tropical conditions for the ARM CART Tropical West Pacific site, and is part of the TOGA COARE experiment. During the latter part of 1992, the radiometer will be tested thoroughly and tested at the Division of Atmospheric Research, Aspendale.

  18. Microwave emissivity of fresh water ice--Lake ice and Antarctic ice pack--Radiative transfer simulations versus satellite radiances

    E-Print Network [OSTI]

    Mills, Peter

    2012-01-01T23:59:59.000Z

    Microwave emissivity models of sea ice are poorly validated empirically. Typical validation studies involve using averaged or stereotyped profiles of ice parameters against averaged radiance measurements. Measurement sites are rarely matched and even less often point-by-point. Because of saline content, complex permittivity of sea ice is highly variable and difficult to predict. Therefore, to check the validity of a typical, plane-parallel, radiative-transfer-based ice emissivity model, we apply it to fresh water ice instead of salt-water ice. Radiance simulations for lake ice are compared with measurements over Lake Superior from the Advanced Microwave Scanning Radiometer on EOS (AMSR-E). AMSR-E measurements are also collected over Antarctic icepack. For each pixel, a thermodynamic model is driven by four years of European Center for Medium Range Weather Forecasts (ECMWF) reanalysis data and the resulting temperature profiles used to drive the emissivity model. The results suggest that the relatively simple ...

  19. Development of a new radiometer for the thermodynamic measurement of high temperature fixed points

    SciTech Connect (OSTI)

    Dury, M. R.; Goodman, T. M.; Lowe, D. H.; Machin, G.; Woolliams, E. R. [National Physical Laboratory, Teddington (United Kingdom)] [National Physical Laboratory, Teddington (United Kingdom)

    2013-09-11T23:59:59.000Z

    The National Physical Laboratory (NPL) has developed a new radiometer to measure the thermodynamic melting point temperatures of high temperature fixed points with ultra-low uncertainties. In comparison with the NPL's Absolute Radiation Thermometer (ART), the 'THermodynamic Optical Radiometer' (THOR) is more portable and compact, with a much lower size-of-source effect and improved performance in other parameters such as temperature sensitivity. It has been designed for calibration as a whole instrument via the radiance method, removing the need to calibrate the individual subcomponents, as required by ART, and thereby reducing uncertainties. In addition, the calibration approach has been improved through a new integrating sphere that has been designed to have greater uniformity.

  20. Electron cyclotron emission radiometer upgrade on the Joint European Torus (JET) tokamak

    SciTech Connect (OSTI)

    Luna, E. de la; Sanchez, J.; Tribaldos, V.; Conway, G.; Suttrop, W.; Fessey, J.; Prentice, R.; Gowers, C.; Chareau, J. M. [Asociacion EURATOM-CIEMAT para Fusion, CIEMAT, Madrid (Spain); IPP-EURATOM Association, Garching (Germany); EURATOM-UKAEA Fusion Associations, Culham Science Centre, Abingdon (United Kingdom); European Commission, Institute for Transuranium Elements, Karlsruhe (Germany)

    2004-10-01T23:59:59.000Z

    The capabilities of the Joint European Torus (JET) electron cyclotron emission (ECE) diagnostics have recently been extended with an upgrading of the heterodyne radiometer. The number of channels has been doubled to 96 channels, with a frequency separation corresponding to <1 cm for JET magnetic field gradient, and with a frequency response of 1 MHz. This enhancement has increased the radial coverage of the ECE electron temperature measurements in JET to approximately the full plasma column (limited at R>2.6 m for the X-mode due to harmonic overlap) at almost all magnetic field values used at JET (1.7 Tradiometer is presented along with some results showing its performance.

  1. A continuous-wave second harmonic gyrotron oscillator at 460 GHz

    E-Print Network [OSTI]

    Hornstein, Melissa K. (Melissa Kristen), 1977-

    2005-01-01T23:59:59.000Z

    We report the short pulse and CW operation of a 460 GHz gyrotron oscillator both at the fundamental (near 230 GHz) and second harmonic (near 460 GHz) of electron cyclotron resonance. During operation in a complete CW regime ...

  2. Absolute intensity calibration of the 32-channel heterodyne radiometer on experimental advanced superconducting tokamak

    SciTech Connect (OSTI)

    Liu, X.; Zhao, H. L.; Liu, Y., E-mail: liuyong@ipp.ac.cn; Li, E. Z.; Han, X.; Ti, A.; Hu, L. Q.; Zhang, X. D. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Domier, C. W.; Luhmann, N. C. [Department of Electrical and Computer Engineering, University of California at Davis, Davis, California 95616 (United States)

    2014-09-15T23:59:59.000Z

    This paper presents the results of the in situ absolute intensity calibration for the 32-channel heterodyne radiometer on the experimental advanced superconducting tokamak. The hot/cold load method is adopted, and the coherent averaging technique is employed to improve the signal to noise ratio. Measured spectra and electron temperature profiles are compared with those from an independent calibrated Michelson interferometer, and there is a relatively good agreement between the results from the two different systems.

  3. Calibration of a 32 channel electron cyclotron emission radiometer on the HL-2A tokamak

    SciTech Connect (OSTI)

    Shi, Z. B., E-mail: shizb@swip.ac.cn; Jiang, M.; Huang, X. L.; Zhong, W. L.; Chen, W.; Che, Y. L.; Liu, Z. T.; Ding, X. T.; Yang, Q. W.; Duan, X. R. [Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041 (China)] [Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041 (China)

    2014-02-15T23:59:59.000Z

    A novel 32-channel electron cyclotron emission radiometer has been designed and tested for the measurement of electron temperature profiles on the HL-2A tokamak. This system is based on the intermediate frequency filter detection technique, and has the features of wide working frequency range and high spatial resolution. Two relative calibration methods have been investigated: sweeping the toroidal magnetic field and hopping the output frequency of the local oscillator. Preliminary results show that both methods can ensure reasonable profiles.

  4. Using a cold radiometer to measure heat loads and survey heat leaks

    SciTech Connect (OSTI)

    DiPirro, M.; Tuttle, J.; Hait, T.; Shirron, P. [Cryogenics and Fluids Branch, NASA/Goddard Space Flight Center, Greenbelt MD 20771 (United States)

    2014-01-29T23:59:59.000Z

    We have developed an inexpensive cold radiometer for use in thermal/vacuum chambers to measure heat loads, characterize emissivity and specularity of surfaces and to survey areas to evaluate stray heat loads. We report here the results of two such tests for the James Webb Space Telescope to measure heat loads and effective emissivities of 2 major pieces of optical ground support equipment that will be used in upcoming thermal vacuum testing of the Telescope.

  5. InGaAs/InP DHBTs with 120-nm Collector Having Simultaneously High ft,fmax > 450 GHz

    E-Print Network [OSTI]

    2005-01-01T23:59:59.000Z

    Simultaneously High f , f max 450 GHz Zach Grif?th, Mark J.devices exhibit a maximum 450 GHz and 490 GHz max , which iscollector. Here, we report a 450 GHz and 490 InP DHBT—the ?

  6. Single Spin Optically Detected Magnetic Resonance with E-Band Microwave Resonators

    E-Print Network [OSTI]

    Nabeel Aslam; Matthias Pfender; Rainer Stöhr; Philipp Neumann; Marc Scheffler; Hitoshi Sumiya; Hiroshi Abe; Shinobu Onoda; Takeshi Ohshima; Junichi Isoya; Jörg Wrachtrup

    2015-03-13T23:59:59.000Z

    Magnetic resonance with ensembles of electron spins is nowadays performed in frequency ranges up to 240 GHz and in corresponding magnetic fields of up to 10 T. However, experiments with single electron and nuclear spins so far only reach into frequency ranges of several 10 GHz, where existing coplanar waveguide structures for microwave (MW) delivery are compatible with single spin readout techniques (e.g. electrical or optical readout). Here, we explore the frequency range up to 90 GHz, respectively magnetic fields of up to $\\approx 3\\,$T for single spin magnetic resonance in conjunction with optical spin readout. To this end, we develop MW resonators with optical single spin access. In our case, rectangular E-band waveguides guarantee low-loss supply of microwaves to the resonators. Three dimensional cavities, as well as coplanar waveguide resonators enhance MW fields by spatial and spectral confinement with a MW efficiency of $1.36\\,\\mathrm{mT/\\sqrt{W}}$. We utilize single NV centers as hosts for optically accessible spins, and show, that their properties regarding optical spin readout known from smaller fields (sensor. Regarding spin based quantum registers, high fields lead to a purer product basis of electron and nuclear spins, which promises improved spin lifetimes. For example, during continuous single-shot readout the $^{14}$N nuclear spin shows second-long longitudinal relaxation times.

  7. Relative Accuracy of 1-Minute and Daily Total Solar Radiation Data for 12 Global and 4 Direct Beam Solar Radiometers: Preprint

    SciTech Connect (OSTI)

    Myers, D. R.; Wilcox, S. M.

    2009-03-01T23:59:59.000Z

    This report evaluates the relative performance of 12 global and four direct beam solar radiometers deployed at a single site over a 12-month period. Test radiometer irradiances were compared with a reference irradiance consisting of either an absolute cavity radiometer (during calibrations) or a low uncertainty thermopile pyrheliometer (during the evaluation period) for pyrheliometers; and for pyranometers a reference global irradiance computed from the reference pyrheliometer and diffuse irradiance from a shaded pyranometer.

  8. A 250 GHz photonic band gap gyrotron amplifier

    E-Print Network [OSTI]

    Nanni, Emilio A. (Emilio Alessandro)

    2013-01-01T23:59:59.000Z

    This thesis reports the theoretical and experimental investigation of a novel gyrotron traveling-wave-tube (TWT) amplifier at 250 GHz. The gyrotron amplifier designed and tested in this thesis has achieved a peak small ...

  9. Design of a wideband, 100 W, 140 GHz gyroklystron amplifier

    E-Print Network [OSTI]

    Joye, Colin D., 1980-

    2004-01-01T23:59:59.000Z

    The design study of a 140 GHz, 100 W continuous wave gyroklystron amplifier is presented. The device is intended for use in Dynamic Nuclear Polarization (DNP) enhanced Nuclear Magnetic Resonance (NMR) spectroscopy experiments. ...

  10. THE IMPACT OF THE SPECTRAL RESPONSE OF AN ACHROMATIC HALF-WAVE PLATE ON THE MEASUREMENT OF THE COSMIC MICROWAVE BACKGROUND POLARIZATION

    SciTech Connect (OSTI)

    Bao, C.; Gold, B.; Hanany, S. [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States); Baccigalupi, C.; Leach, S. [SISSA, Astrophysics Sector, Via Bonomea 265, Trieste 34136 (Italy); Didier, J.; Johnson, B. R.; Miller, A. [Department of Physics, Columbia University, New York, NY 10027 (United States); Jaffe, A.; O'Dea, D. [Department of Physics, Imperial College, London SW72AZ (United Kingdom); Matsumura, T. [High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan)

    2012-03-10T23:59:59.000Z

    We study the impact of the spectral dependence of the linear polarization rotation induced by an achromatic half-wave plate on measurements of cosmic microwave background polarization in the presence of astrophysical foregrounds. We focus on the systematic effects induced on the measurement of inflationary gravitational waves by uncertainties in the polarization and spectral index of Galactic dust. We find that for the experimental configuration and noise levels of the balloon-borne EBEX experiment, which has three frequency bands centered at 150, 250, and 410 GHz, a crude dust subtraction process mitigates systematic effects to below detectable levels for 10% polarized dust and tensor-to-scalar ratio of as low as r = 0.01. We also study the impact of uncertainties in the spectral response of the instrument. With a top-hat model of the spectral response for each band, characterized by band center and bandwidth, and with the same crude dust subtraction process, we find that these parameters need to be determined to within 1 and 0.8 GHz at 150 GHz; 9 and 2.0 GHz at 250 GHz; and 20 and 14 GHz at 410 GHz, respectively. The approach presented in this paper is applicable to other optical elements that exhibit polarization rotation as a function of frequency.

  11. 60 GHz ecrh system for the PPL PDX machine

    SciTech Connect (OSTI)

    Bowen, N.; Doane, J.; Newman, W.

    1981-01-01T23:59:59.000Z

    A 60-GHz kW Electron Cyclotron Resonance (ECR) heating system for the PDX machine is now under construction. It will use two of the pulse-type 60 GHz gyrotrons now being developed by Varian for the U.S. Department of Energy under a subcontract for Oak Ridge National Laboratory. The system will be used for various temperature profile, start-up, and heating experiments. This paper describes the design of the system and its physical configuration.

  12. OAK 270 - The use of Lidar/radiometer (LIRAD) in the ARM program to obtain optical properties and microphysics of high and midlevel clouds

    SciTech Connect (OSTI)

    C.M.R. Platt; R.T. Austin; S.A. Young; and G.L. Stephens

    2002-12-13T23:59:59.000Z

    OAK 270 - The use of Lidar/Radiometer (LIRAD) in the ARM program to obtain optical properties and microphysics of high and midlevel clouds

  13. Microwave hematoma detector

    DOE Patents [OSTI]

    Haddad, Waleed S. (Dublin, CA); Trebes, James E. (Livermore, CA); Matthews, Dennis L. (Moss Beach, CA)

    2001-01-01T23:59:59.000Z

    The Microwave Hematoma Detector is a non-invasive device designed to detect and localize blood pooling and clots near the outer surface of the body. While being geared towards finding sub-dural and epi-dural hematomas, the device can be used to detect blood pooling anywhere near the surface of the body. Modified versions of the device can also detect pneumothorax, organ hemorrhage, atherosclerotic plaque in the carotid arteries, evaluate perfusion (blood flow) at or near the body surface, body tissue damage at or near the surface (especially for burn assessment) and be used in a number of NDE applications. The device is based on low power pulsed microwave technology combined with a specialized antenna, signal processing/recognition algorithms and a disposable cap worn by the patient which will facilitate accurate mapping of the brain and proper function of the instrument. The invention may be used for rapid, non-invasive detection of sub-dural or epi-dural hematoma in human or animal patients, detection of hemorrhage within approximately 5 cm of the outer surface anywhere on a patient's body.

  14. Predictions of microwavePredictions of microwave breakdown in rf structuresbreakdown in rf structures

    E-Print Network [OSTI]

    Yu, Ming

    Predictions of microwave breakdownPredictions of microwave breakdown in rf structuresin rf structures #12;2 of the breakdown phenomenon). 2. Electron interaction with microwave field (rough estimates of parameters which in communication systems Predictions of microwave breakdown in rf structuresPredictions of microwave breakdown

  15. Application of vane-type resonator to microwave powered electrodeless HID lamp

    SciTech Connect (OSTI)

    Hochi, Akira; Takeda, Mamoru

    1999-07-01T23:59:59.000Z

    A cavity resonator has been generally used as microwave applicator for an electrodeless high intensity discharge (HID) lamp. The size of a cavity resonator is determined by the wavelength of a microwave applied. For example, for a microwave of 2.45 GHz, an inner diameter of more than about 76 mm is necessary for obtaining a microwave resonant field, and then the size of a plasma arc capable of maintaining a stable discharge is experimentally limited at about 15 mm and above. Accordingly the microwave powered electrodeless HID lamp device using cavity resonator is inappropriate in applications where a point light source is required. A vane-type resonator is generally known as an anode of a magnetron, which decides the oscillation frequency of the magnetron. The authors used 3-D finite element method simulation for a design of a vane-type resonator with parabolic reflector to obtain a desired resonant frequency. According to the results of the simulation, the sizes of a 4-vanes resonator with the parabolic reflector were decided, and the resonator made of aluminum and copper was prepared. An electrodeless lamp with InBr and Ar gas enclosed in a spherical quartz glass tube having an inner diameter of about 4 mm was also prepared, and was set at center portion of the resonator. The total luminous flux was about 2,150 lm at microwave input of 27 W. Incidentally, the CRI and Tc for this lamp were 93 and 10,200 K, respectively. Thus, it becomes possible to efficiently couple microwave energy with a smaller-sized electrodeless HID lamp than conventional.

  16. Microwave-driven ultraviolet light sources

    SciTech Connect (OSTI)

    Manos, Dennis M. (Williamsburg, VA); Diggs, Jessie (Norfolk, VA); Ametepe, Joseph D. (Roanoke, VA)

    2002-01-29T23:59:59.000Z

    A microwave-driven ultraviolet (UV) light source is provided. The light source comprises an over-moded microwave cavity having at least one discharge bulb disposed within the microwave cavity. At least one magnetron probe is coupled directly to the microwave cavity.

  17. Temperature and density evolution during decay in a 2.45 GHz hydrogen electron cyclotron resonance plasma: Off-resonant and resonant cases

    SciTech Connect (OSTI)

    Cortázar, O. D. [ESS Bilbao, Edificio Cosimet, Landabarri 2, 48940-Leioa, Vizcaya (Spain) [ESS Bilbao, Edificio Cosimet, Landabarri 2, 48940-Leioa, Vizcaya (Spain); Universidad de Castilla-La Mancha, ETSII, C.J. Cela s/n, 13170 Ciudad Real (Spain); Megía-Macías, A.; Vizcaíno-de-Julián, A. [ESS Bilbao, Edificio Cosimet, Landabarri 2, 48940-Leioa, Vizcaya (Spain)] [ESS Bilbao, Edificio Cosimet, Landabarri 2, 48940-Leioa, Vizcaya (Spain)

    2013-09-15T23:59:59.000Z

    Time resolved electron temperature and density measurements during the decay stage in a hydrogen electron cyclotron resonance (ECR) plasma are presented for a resonance and off-resonance magnetic field configurations. The measurements are conducted on a ECR plasma generator excited at 2.45 GHz denominated test-bench for ion-sources plasma studies at ESS Bilbao. The plasma parameters evolution is studied by Langmuir probe diagnostic with synchronized sample technique developed for repetitive pulsed plasmas with a temporal resolution of 200 ns in typical decay processes of about 40 ?s. An afterglow transient is clearly observed in the reflected microwave power signal from the plasma. Simultaneously, the electron temperature evolution shows rebounding peaks that may be related to the interplay between density drop and microwave coupling with deep impact on the Electron Energy Distribution Function. The correlation of such structures with the plasma absorbed power and the coupling quality is also reported.

  18. First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Foreground Emission

    E-Print Network [OSTI]

    C. Bennett; R. S. Hill; G. Hinshaw; M. R. Nolta; N. Odegard; L. Page; D. N. Spergel; J. L. Weiland; E. L. Wright; M. Halpern; N. Jarosik; A. Kogut; M. Limon; S. S. Meyer; G. S. Tucker; E. Wollack

    2003-06-05T23:59:59.000Z

    Full sky maps are made in five microwave frequency bands to separate the temperature anisotropy of the CMB from foreground emission. We define masks that excise regions of high foreground emission. The effectiveness of template fits to remove foreground emission from the WMAP data is examined. These efforts result in a CMB map with minimal contamination and a demonstration that the WMAP CMB power spectrum is insensitive to residual foreground emission. We construct a model of the Galactic emission components. We find that the Milky Way resembles other normal spiral galaxies between 408 MHz and 23 GHz, with a synchrotron spectral index that is flattest (beta ~ -2.5) near star-forming regions, especially in the plane, and steepest (beta ~ -3) in the halo. The significant synchrotron index steepening out of the plane suggests a diffusion process in which the halo electrons are trapped in the Galactic potential long enough to suffer synchrotron and inverse Compton energy losses and hence a spectral steepening. The synchrotron index is steeper in the WMAP bands than in lower frequency radio surveys, with a spectral break near 20 GHz to beta < -3. The modeled thermal dust spectral index is also steep in the WMAP bands, with beta ~ 2.2. Microwave and H alpha measurements of the ionized gas agree. Spinning dust emission is limited to < ~5% of the Ka-band foreground emission. A catalog of 208 point sources is presented. Derived source counts suggest a contribution to the anisotropy power from unresolved sources of (15.0 +- 1.4) 10^{-3} microK^2 sr at Q-band and negligible levels at V-band and W-band.

  19. Macrocyclic polyaminocarboxylates for stable radiometal antibody conjugates for therapy, SPECT and PET imaging

    DOE Patents [OSTI]

    Mease, R.C.; Mausner, L.F.; Srivastava, S.C.

    1997-06-17T23:59:59.000Z

    A simple method for the synthesis of 1,4,7, 10-tetraazacyclododecane N,N{prime}N{double_prime},N{prime}{double_prime}-tetraacetic acid and 1,4,8,11-tetraazacyclotetradecane N,N{prime},N{double_prime},N{prime}{double_prime}-tetraacetic acid involves cyanomethylating 1,4,7,10-tetraazacyclododecane or 1,4,8,11-tetraazacyclotetradecane to form a tetranitrile and hydrolyzing the tetranitrile. These macrocyclic compounds are functionalized through one of the carboxylates and then conjugated to various biological molecules including monoclonal antibodies. The resulting conjugated molecules are labeled with radiometals for SPECT and PET imaging and for radiotherapy. 4 figs.

  20. Macrocyclic polyaminocarboxylates for stable radiometal antibody conjugates for therapy, spect and pet imaging

    DOE Patents [OSTI]

    Mease, Ronnie C. (Fairfax, VA); Mausner, Leonard F. (Stony Brook, NY); Srivastava, Suresh C. (Setauket, NY)

    1997-06-17T23:59:59.000Z

    A simple method for the synthesis of 1,4,7, 10-tetraazacyclododecane N,N'N",N'"-tetraacetic acid and 1,4,8,11-tetraazacyclotetradecane N,N',N",N'"-tetraacetic acid involves cyanomethylating 1,4,7, 10-tetraazacyclododecane or 1,4,8,11-tetraazacyclotetradecane to form a tetranitrile and hydrolyzing the tetranitrile. These macrocyclic compounds are functionalized through one of the carboxylates and then conjugated to various biological molecules including monoclonal antibodies. The resulting conjugated molecules are labeled with radiometals for SPECT and PET imaging and for radiotherapy.

  1. Microwave Regenerated DPF for Auxiliary Power Units and Diesel...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Microwave Regenerated DPF for Auxiliary Power Units and Diesel Hybrid Vehicles Microwave Regenerated DPF for Auxiliary Power Units and Diesel Hybrid Vehicles Microwave regeneration...

  2. Gigatron microwave amplifier

    DOE Patents [OSTI]

    McIntyre, P.M.

    1993-07-13T23:59:59.000Z

    An electron tube for achieving high power at high frequency with high efficiency is described, including an input coupler, a ribbon-shaped electron beam and a traveling wave output coupler. The input coupler is a lumped constant resonant circuit that modulates a field emitter array cathode at microwave frequency. A bunched ribbon electron beam is emitted from the cathode in periodic bursts at the desired frequency. The beam has a ribbon configuration to eliminate limitations inherent in round beam devices. The traveling wave coupler efficiently extracts energy from the electron beam, and includes a waveguide with a slot there through for receiving the electron beam. The ribbon beam is tilted at an angle with respect to the traveling wave coupler so that the electron beam couples in-phase with the traveling wave in the waveguide. The traveling wave coupler thus extracts energy from the electron beam over the entire width of the beam.

  3. Gigatron microwave amplifier

    DOE Patents [OSTI]

    McIntyre, Peter M. (611 Montclair, College Station, TX 77840)

    1993-01-01T23:59:59.000Z

    An electron tube for achieving high power at high frequency with high efficiency, including an input coupler, a ribbon-shaped electron beam and a traveling wave output coupler. The input coupler is a lumped constant resonant circuit that modulates a field emitter array cathode at microwave frequency. A bunched ribbon electron beam is emitted from the cathode in periodic bursts at the desired frequency. The beam has a ribbon configuration to eliminate limitations inherent in round beam devices. The traveling wave coupler efficiently extracts energy from the electron beam, and includes a waveguide with a slot therethrough for receiving the electron beam. The ribbon beam is tilted at an angle with respect to the traveling wave coupler so that the electron beam couples in-phase with the traveling wave in the waveguide. The traveling wave coupler thus extracts energy from the electron beam over the entire width of the beam.

  4. Cosmic Microwave Background Polarization

    E-Print Network [OSTI]

    James G. Bartlett

    2006-04-18T23:59:59.000Z

    Cosmic microwave background (CMB) anisotropy is our richest source of cosmological information; the standard cosmological model was largely established thanks to study of the temperature anisotropies. By the end of the decade, the Planck satellite will close this important chapter and move us deeper into the new frontier of polarization measurements. Numerous ground--based and balloon--borne experiments are already forging into this new territory. Besides providing new and independent information on the primordial density perturbations and cosmological parameters, polarization measurements offer the potential to detect primordial gravity waves, constrain dark energy and measure the neutrino mass scale. A vigorous experimental program is underway worldwide and heading towards a new satellite mission dedicated to CMB polarization.

  5. STATISTICAL PROPERTIES OF 12.2 GHz METHANOL MASERS ASSOCIATED WITH A COMPLETE SAMPLE OF 6.7 GHz METHANOL MASERS

    SciTech Connect (OSTI)

    Breen, S. L.; Caswell, J. L.; Green, J. A.; Voronkov, M. A. [CSIRO Astronomy and Space Science, P.O. Box 76, Epping, NSW 1710 (Australia); Ellingsen, S. P. [School of Mathematics and Physics, University of Tasmania, Private Bag 37, Hobart, Tasmania 7001 (Australia); Fuller, G. A.; Quinn, L. J.; Avison, A., E-mail: Shari.Breen@csiro.au [Jodrell Bank Centre for Astrophysics, Alan Turing Building, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom)

    2011-06-01T23:59:59.000Z

    We present definitive detection statistics for 12.2 GHz methanol masers toward a complete sample of 6.7 GHz methanol masers detected in the Methanol Multibeam survey south of declination -20{sup 0}. In total, we detect 250 12.2 GHz methanol masers toward 580 6.7 GHz methanol masers. This equates to a detection rate of 43.1%, which is lower than that of previous significant searches of comparable sensitivity. Both the velocity ranges and the flux densities of the target 6.7 GHz sources surpass that of their 12.2 GHz companion in almost all cases. Eighty percent of the detected 12.2 GHz methanol maser peaks are coincident in velocity with the 6.7 GHz maser peak. Our data support an evolutionary scenario whereby the 12.2 GHz sources are associated with a somewhat later evolutionary stage than the 6.7 GHz sources devoid of this transition. Furthermore, we find that the 6.7 GHz and 12.2 GHz methanol sources increase in luminosity as they evolve. In addition to this, evidence for an increase in velocity range with evolution is presented. This implies that it is not only the luminosity but also the volume of gas conducive to the different maser transitions that increases as the sources evolve. Comparison with GLIMPSE mid-infrared sources has revealed a coincidence rate between the locations of the 6.7 GHz methanol masers and GLIMPSE point sources similar to that achieved in previous studies. Overall, the properties of the GLIMPSE sources with and without 12.2 GHz counterparts are similar. There is a higher 12.2 GHz detection rate toward those 6.7 GHz methanol masers that are coincident with extended green objects.

  6. Bayesian modeling of microwave foregrounds

    E-Print Network [OSTI]

    Rahlin, Alexandra Sasha

    2008-01-01T23:59:59.000Z

    In the past decade, advances in precision cosmology have pushed our understanding of the evolving Universe to new limits. Since the discovery of the cosmic microwave background (CMB) radiation in 1965 by Penzias and Wilson, ...

  7. SLOW MAGNETOACOUSTIC OSCILLATIONS IN THE MICROWAVE EMISSION OF SOLAR FLARES

    SciTech Connect (OSTI)

    Kim, S.; Shibasaki, K. [Nobeyama Solar Radio Observatory/NAOJ, Nagano 384-1305 (Japan); Nakariakov, V. M., E-mail: sjkim@nro.nao.ac.jp [Physics Department, University of Warwick, Coventry, CV4 7AL (United Kingdom)

    2012-09-10T23:59:59.000Z

    Analysis of the microwave data, obtained in the 17 GHz channel of the Nobeyama Radioheliograph during the M1.6 flare on 2010 November 4, revealed the presence of 12.6 minute oscillations of the emitting plasma density. The oscillations decayed with the characteristic time of about 15 minutes. Similar oscillations with the period of about 13.8 minutes and the decay time of 25 minutes are also detected in the variation of EUV emission intensity measured in the 335 A channel of the Solar Dynamics Observatory/Atmospheric Imaging Assembly. The observed properties of the oscillations are consistent with the oscillations of hot loops observed by the Solar and Heliospheric Observatory/Solar Ultraviolet Measurement of Emitted Radiation (SUMER) in the EUV spectra in the form of periodic Doppler shift. Our analysis presents the first direct observations of the slow magnetoacoustic oscillations in the microwave emission of a solar flare, complementing accepted interpretations of SUMER hot loop oscillations as standing slow magnetoacoustic waves.

  8. Tunable microwave impedance matching to a high impedance source using a Josephson metamaterial

    SciTech Connect (OSTI)

    Altimiras, Carles, E-mail: carles.altimiras@sns.it; Parlavecchio, Olivier; Joyez, Philippe; Vion, Denis; Roche, Patrice; Esteve, Daniel; Portier, Fabien [Service de Physique de l’Etat Condensé (CNRS URA 2464), IRAMIS, CEA Saclay, 91191 Gif-sur-Yvette (France)] [Service de Physique de l’Etat Condensé (CNRS URA 2464), IRAMIS, CEA Saclay, 91191 Gif-sur-Yvette (France)

    2013-11-18T23:59:59.000Z

    We report the efficient coupling of a 50??? microwave circuit to a high impedance conductor. We use an impedance transformer consisting of a ?/4 co-planar resonator whose inner conductor contains an array of superconducting quantum interference devices (SQUIDs), providing it with a tunable lineic inductance L?80??{sub 0}, resulting in a characteristic impedance Z{sub C}?1?k?. The impedance matching efficiency is characterized by measuring the shot noise power emitted by a dc biased tunnel junction connected to the resonator. We demonstrate matching to impedances in the 15 to 35?k? range with bandwidths above 100?MHz around a resonant frequency tunable between 4 and 6 GHz.

  9. Microwave power spectral density and its effects on exciting electrodeless high intensity discharge lamps

    SciTech Connect (OSTI)

    Butler, S.J.; Goss, H.H.; Lapatovich, W.P. [Osram Sylvania Inc., Salem, MA (United States)

    1995-12-31T23:59:59.000Z

    The effects of a microwave source generating a spectrally dense power spectrum on the operation of an electrodeless high intensity discharge lamp were measured. Spectrally pure sources operating within ISM bands at 915 MHz and 2.45 GHz produce stable capacitively coupled discharges useful for producing flicker-free light for numerous applications. The internal plasma temperature distribution and lamp geometry define acoustic resonance modes within the lamp which can be excited with power sidebands. The operation of lamps with commercially available power sources and custom built generators are discussed. Estimates of the spectral purity required for stable operation are provided.

  10. Retrieval of Optical And Size Parameters of Aerosols Utilizing a Multi-Filter Rotating Shadowband Radiometer and Inter-Comparison with CIMEL Sun Photometer and

    E-Print Network [OSTI]

    Radiometer and Inter-Comparison with CIMEL Sun Photometer and MICROTOPS Sun Photometer Antonio Aguirre Radiometer (MFRSR) and comparing with data from a CIMEL Sun Photometer and a MICROTOPS Sun Photometer. Using the inverse cosine of the angle between the sun and the vertical. A Langley plot provides a linear regression

  11. Temporally and spatially resolved characterization of microwave induced argon plasmas: Experiment and modeling

    SciTech Connect (OSTI)

    Baeva, M., E-mail: baeva@inp-greifswald.de; Andrasch, M.; Ehlbeck, J.; Loffhagen, D.; Weltmann, K.-D. [INP Greifswald, Felix-Hausdorff-Str. 2, 17489 Greifswald (Germany)

    2014-04-14T23:59:59.000Z

    Experiments and modeling of the plasma-microwave interaction have been performed in a coaxial microwave plasma source at a field frequency of 2.45 GHz generating argon plasmas at pressures of 20 and 40 millibars and a ratio of flow rate to pressure of 0.125 sccm/Pa. The incident microwave power between 100?W and 300?W is supplied in a regime of a pulse-width modulation with cycle duration of 110?ms and a power-on time of 23?ms. The experiments are based on heterodyne reflectometry and microwave interferometry at 45.75?GHz. They provide the temporal behaviour of the complex reflection coefficient, the microwave power in the plasma, as well as the electron density in the afterglow zone of the discharge. The self-consistent spatially two-dimensional and time-dependent modeling complements the analysis of the plasma-microwave interaction delivering the plasma and electromagnetic field parameters. The consolidating experimental observations and model predictions allow further characterizing the plasma source. The generated plasma has a core occupying the region close to the end of the inner electrode, where maximum electron densities above 10{sup 20}?m{sup ?3} and electron temperatures of about 1?eV are observed. Due to a longer outer electrode of the coaxial structure, the plasma region is extended and fills the volume comprised by the outer electrode. The electron density reaches values of the order of 10{sup 19}?m{sup ?3}. The heating of the gas occurs in its great part due to elastic collisions with the plasma electrons. However, the contribution of the convective heating is important especially in the extended plasma region, where the gas temperature reaches its maximum values up to approximately 1400?K. The temporally and spatially resolved modeling enables a thorough investigation of the plasma-microwave interaction which clearly shows that the power in-coupling occurs in the region of the highest electron density during the early stage of the discharge. In the steady state phase, however, the power in-coupling occurs close to the source walls where the electron density is significantly lower than on the discharge axis.

  12. Studies on the coupling transformer to improve the performance of microwave ion source

    SciTech Connect (OSTI)

    Misra, Anuraag, E-mail: pandit@vecc.gov.in, E-mail: vspandit12@gmail.com, E-mail: anuraag@vecc.gov.in; Pandit, V. S., E-mail: pandit@vecc.gov.in, E-mail: vspandit12@gmail.com, E-mail: anuraag@vecc.gov.in [Variable Energy Cyclotron Centre, 1- AF, Bidhannagar, Kolkata 700064 (India)

    2014-06-15T23:59:59.000Z

    A 2.45 GHz microwave ion source has been developed and installed at the Variable Energy Cyclotron Centre to produce high intensity proton beam. It is operational and has already produced more than 12 mA of proton beam with just 350 W of microwave power. In order to optimize the coupling of microwave power to the plasma, a maximally flat matching transformer has been used. In this paper, we first describe an analytical method to design the matching transformer and then present the results of rigorous simulation performed using ANSYS HFSS code to understand the effect of different parameters on the transformed impedance and reflection and transmission coefficients. Based on the simulation results, we have chosen two different coupling transformers which are double ridged waveguides with ridge widths of 24 mm and 48 mm. We have fabricated these transformers and performed experiments to study the influence of these transformers on the coupling of microwave to plasma and extracted beam current from the ion source.

  13. Microwave heating apparatus and method

    DOE Patents [OSTI]

    Johnson, Andrew J. (Boulder, CO); Petersen, Robert D. (Thornton, CO); Swanson, Stephen D. (Brighton, CO)

    1990-01-01T23:59:59.000Z

    An apparatus is provided for heating and melting materials using microwave energy, and for permitting them to solidify. The apparatus includes a microwave energy source, a resonant cavity having an opening in its floor, a microwave energy choke encompassing the opening in the floor of the cavity, a metal container to hold the materials to be heated and melted, a turntable, and a lift-table. During operation, the combined action of the turntable and the lift-table position the metal container so that the top of the container is level with the floor of the cavity, is in substantial registration with the floor opening, and is encompassed by the microwave energy choke; thus, during operation, the interior of the container defines part of the resonant cavity. Additionally, a screw feeder, extending into the cavity and sheltered from microwave energy by a conveyor choke, may convey the materials to be heated to the container. Also, preferably, the floor of the resonant cavity may include perforatins, so that the offgases and dust generated in the apparatus may be removed from the resonant cavity by pulling outside air between the container choke and the exterior wall of the container into the resonant cavity and out from the cavity through the perforations.

  14. Introduction to Scanning Microwave Microscopy Mode

    E-Print Network [OSTI]

    Anlage, Steven

    Wenhai Han Introduction to Scanning Microwave Microscopy Mode Application Note Introduction Mapping through" and meanwhile achieve sufficient sensitivity and resolution. With the invention of scanning been developed to probe materials properties. These include scanning near-field to scanning microwave

  15. SLAC All Access: Vacuum Microwave Device Department

    ScienceCinema (OSTI)

    Haase, Andy

    2014-06-13T23:59:59.000Z

    The Vacuum Microwave Device Department (VMDD) builds the devices that make SLAC's particle accelerators go. These devices, called klystrons, generate intense waves of microwave energy that rocket subatomic particles up to nearly the speed of light.

  16. A 76GHz PLL for mm-wave imaging applications

    E-Print Network [OSTI]

    Nguyen, Khoa M.

    A 76 GHz phase-locked loop (PLL) was designed in 0.13 ?m IBM BiCMOS8HP technology with the intended application of millimeter-wave imaging. The PLL has a type II second order loop filter. The voltage-controlled oscillator ...

  17. 60 GHz High Data Rate Wireless Communication System

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    amplifiers (PAs) non-linearities. OFDM requires large back-off for PAs, high stability and low phase noise.zaharia@insa-rennes.fr; ghais.el-zein@insa-rennes. Abstract ­ This paper presents the design and the realization of a 60 GHz analyzed to develop new MMW communication systems for commercial applications [1-2]. Due to the large

  18. Solar Irradiances Measured using SPN1 Radiometers: Uncertainties and Clues for Development

    SciTech Connect (OSTI)

    Badosa, Jordi; Wood, John; Blanc, Philippe; Long, Charles N.; Vuilleumier, Laurent; Demengel, Dominique; Haeffelin, Martial

    2014-12-08T23:59:59.000Z

    The fast development of solar radiation and energy applications, such as photovoltaic and solar thermodynamic systems, has increased the need for solar radiation measurement and monitoring, not only for the global component but also the diffuse and direct. End users look for the best compromise between getting close to state-of-the-art measurements and keeping capital, maintenance and operating costs to a minimum. Among the existing commercial options, SPN1 is a relatively low cost solar radiometer that estimates global and diffuse solar irradiances from seven thermopile sensors under a shading mask and without moving parts. This work presents a comprehensive study of SPN1 accuracy and sources of uncertainty, which results from laboratory experiments, numerical modeling and comparison studies between measurements from this sensor and state-of-the art instruments for six diverse sites. Several clues are provided for improving the SPN1 accuracy and agreement with state-of-the-art measurements.

  19. Ignition methods and apparatus using microwave energy

    DOE Patents [OSTI]

    DeFreitas, Dennis M. (Oxford, NY); Darling, Timothy W. (Los Alamos, NM); Migliori, Albert (Santa Fe, NM); Rees, Daniel E. (Los Alamos, NM)

    1997-01-01T23:59:59.000Z

    An ignition apparatus for a combustor includes a microwave energy source that emits microwave energy into the combustor at a frequency within a resonant response of the combustor, the combustor functioning as a resonant cavity for the microwave energy so that a plasma is produced that ignites a combustible mixture therein. The plasma preferably is a non-contact plasma produced in free space within the resonant cavity spaced away from with the cavity wall structure and spaced from the microwave emitter.

  20. Informal Preliminary Report on Comparisons of Prototype SPN-1 Radiometer to PARSL Measurements

    SciTech Connect (OSTI)

    Long, Charles N.

    2014-06-17T23:59:59.000Z

    The prototype SPN-1 has been taking measurements for several months collocated with our PNNL Atmospheric Remote Sensing Laboratory (PARSL) solar tracker mounted instruments at the Pacific Northwest National Laboratory (PNNL) located in Richland, Washington, USA. The PARSL radiometers used in the following comparisons consist of an Eppley Normal Incident Pyrheliometer (NIP) and a shaded Eppley model 8-48 “Black and White” pyrgeometer (B&W) to measure the direct and diffuse shortwave irradiance (SW), respectively. These instruments were calibrated in mid-September by comparison to an absolute cavity radiometer directly traceable to the world standard group in Davos, Switzerland. The NIP calibration was determined by direct comparison, while the B&W was calibrated using the shade/unshade technique. All PARSL data prior to mid-September have been reprocessed using the new calibration factors. The PARSL data are logged as 1-minute averages from 1-second samples. Data used in this report span the time period from June 22 through December 1, 2006. All data have been processed through the QCRad code (Long and Shi, 2006), which itself is a more elaborately developed methodology along the lines of that applied by the Baseline Surface Radiation Network (BSRN) Archive (Long and Dutton, 2004), for quality control. The SPN-1 data are the standard total and diffuse SW values obtained from the analog data port of the instrument. The comparisons use only times when both the PARSL and SPN-1 data passed all QC testing. The data were further processed and analyzed by application of the SW Flux Analysis methodology (Long and Ackerman, 2000; Long and Gaustad, 2004, Long et al., 2006) to detect periods of clear skies, calculate continuous estimates of clear-sky SW irradiance and the effect of clouds on the downwelling SW, and estimate fractional sky cover.

  1. Effect of Land Surface Heterogeneity on Satellite Near-

    E-Print Network [OSTI]

    Walker, Jeff

    in regulating the energy and water balance at the soil surface and it is therefore a crucial variable for many. SMOS will carry an L-band (1.4GHz) microwave radiometer and will provide near-surface soil moisture highly heterogeneous land surface conditions. The principal objectives of this research are to (i) test

  2. Microwavable thermal energy storage material

    DOE Patents [OSTI]

    Salyer, Ival O. (Dayton, OH)

    1998-09-08T23:59:59.000Z

    A microwavable thermal energy storage material is provided which includes a mixture of a phase change material and silica, and a carbon black additive in the form of a conformable dry powder of phase change material/silica/carbon black, or solid pellets, films, fibers, moldings or strands of phase change material/high density polyethylene/ethylene-vinyl acetate/silica/carbon black which allows the phase change material to be rapidly heated in a microwave oven. The carbon black additive, which is preferably an electrically conductive carbon black, may be added in low concentrations of from 0.5 to 15% by weight, and may be used to tailor the heating times of the phase change material as desired. The microwavable thermal energy storage material can be used in food serving applications such as tableware items or pizza warmers, and in medical wraps and garments.

  3. Microwavable thermal energy storage material

    DOE Patents [OSTI]

    Salyer, I.O.

    1998-09-08T23:59:59.000Z

    A microwavable thermal energy storage material is provided which includes a mixture of a phase change material and silica, and a carbon black additive in the form of a conformable dry powder of phase change material/silica/carbon black, or solid pellets, films, fibers, moldings or strands of phase change material/high density polyethylene/ethylene vinyl acetate/silica/carbon black which allows the phase change material to be rapidly heated in a microwave oven. The carbon black additive, which is preferably an electrically conductive carbon black, may be added in low concentrations of from 0.5 to 15% by weight, and may be used to tailor the heating times of the phase change material as desired. The microwavable thermal energy storage material can be used in food serving applications such as tableware items or pizza warmers, and in medical wraps and garments. 3 figs.

  4. Microwave assisted centrifuge and related methods

    DOE Patents [OSTI]

    Meikrantz, David H. (Idaho Falls, ID) [Idaho Falls, ID

    2010-08-17T23:59:59.000Z

    Centrifuge samples may be exposed to microwave energy to heat the samples during centrifugation and to promote separation of the different components or constituents of the samples using a centrifuge device configured for generating microwave energy and directing the microwave energy at a sample located in the centrifuge.

  5. Microwave treatment of vulcanized rubber

    DOE Patents [OSTI]

    Wicks, George G. (Aiken, SC); Schulz, Rebecca L. (Aiken, SC); Clark, David E. (Gainesville, FL); Folz, Diane C. (Gainesville, FL)

    2002-07-16T23:59:59.000Z

    A process and resulting product is provided in which a vulcanized solid particulate, such as vulcanized crumb rubber, has select chemical bonds broken by microwave radiation. The direct application of microwaves in combination with uniform heating of the crumb rubber renders the treated crumb rubber more suitable for use in new rubber formulations. As a result, larger particle sizes and/or loading levels of the treated crumb rubber can be used in new rubber mixtures to produce recycled composite products with good properties.

  6. Microwave emissions from police radar

    E-Print Network [OSTI]

    Fink, John Michael

    1994-01-01T23:59:59.000Z

    MICROWAVE EMISSIONS FROM POLICE RADAR A Thesis by JOHN MICHAEL FINK Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August 1994 Major Subject...: Industrial Hygiene MICROWAVE EMISSIONS FROM POLICE RADAR A Thesis by JOHN MICHAEL FINK Submitted to Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE John P. Wag (Chair of Committee) Jero e J. C...

  7. Self-aligned InGaP/GaAs heterojunction bipolar transistors for microwave power application

    SciTech Connect (OSTI)

    Ren, F.; Abernathy, C.R.; Pearton, S.J.; Lothian, J.R.; Wisk, P.W.; Fullowan, T.R.; Youngkai Chen (AT and T Bell Labs., Murray Hill, NJ (United States)); Yang, L.W.; Fu, S.T.; Brozovich, R.S. (General Electric Co., Syracuse, NY (USSR))

    1993-07-01T23:59:59.000Z

    As an alternative to AlGaAs/GaAs heterojunction bipolar transistors (HBT's) for microwave applications, InGaP/ GaAs HBT's with carbon-doped base layers grown by metal organic molecular beam epitaxy (MOMBE) are demonstrated with excellent dc, RF, and microwave performance. As previously reported, with a 700-[angstrom]-thick base layer (135-[Omega]/[open square] sheet resistance), a dc current gain of 25, and cutoff frequency and maximum frequency of oscillation above 70 GHz were measured for a 2 [times] 5-[mu]m[sup 2] emitter area device. A device with 12 cells, each consisting of a 2 [times] 15-[mu] m[sup 2] emitter area device for a total emitter area of 360 [mu] m[sup 2], was power tested at 4 GHz under continuous-wave (CW) bias condition. The device delivered 0.6-W output power with 13-dB linear gain and a power-added efficiency of 50%.

  8. Adhesive bonding using variable frequency microwave energy

    DOE Patents [OSTI]

    Lauf, Robert J. (Oak Ridge, TN); McMillan, April D. (Knoxville, TN); Paulauskas, Felix L. (Oak Ridge, TN); Fathi, Zakaryae (Cary, NC); Wei, Jianghua (Raleigh, NC)

    1998-01-01T23:59:59.000Z

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy.

  9. Adhesive bonding using variable frequency microwave energy

    DOE Patents [OSTI]

    Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.; Fathi, Z.; Wei, J.

    1998-09-08T23:59:59.000Z

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy. 26 figs.

  10. Adhesive bonding using variable frequency microwave energy

    DOE Patents [OSTI]

    Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.; Fathi, Z.; Wei, J.

    1998-08-25T23:59:59.000Z

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy. 26 figs.

  11. Global longterm passive microwave satellitebased retrievals of vegetation optical depth

    E-Print Network [OSTI]

    Evans, Jason

    with those observed in the Advanced Very High Resolution Radiometer (AVHRR) Normalized Difference Vegetation the Advanced Very High Resolution Radiometer (AVHRR) extending back to 1981. The NDVI is derived by subtracting in the hydrological, energy and carbon cycles, through influences of land cover change on hydrologic responses

  12. Microwave sintering of boron carbide

    DOE Patents [OSTI]

    Blake, R.D.; Katz, J.D.; Petrovic, J.J.; Sheinberg, H.

    1988-06-10T23:59:59.000Z

    A method for forming boron carbide into a particular shape and densifying the green boron carbide shape. Boron carbide in powder form is pressed into a green shape and then sintered, using a microwave oven, to obtain a dense boron carbide body. Densities of greater than 95% of theoretical density have been obtained. 1 tab.

  13. Controlled zone microwave plasma system

    DOE Patents [OSTI]

    Ripley, Edward B. (Knoxville, TN); Seals, Roland D. (Oak Ridge, TN); Morrell, Jonathan S. (Knoxville, TN)

    2009-10-20T23:59:59.000Z

    An apparatus and method for initiating a process gas plasma. A conductive plate having a plurality of conductive fingers is positioned in a microwave applicator. An arc forms between the conductive fingers to initiate the formation of a plasma. A transport mechanism may convey process materials through the plasma. A spray port may be provided to expel processed materials.

  14. MMS 2007 Mediterranean Microwave Symposium

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    and the radiating slots. The design was based on electromagnetic simulations made using the CST Microwave Studio substrate metallization has been used to improve radiation properties. The simulated radiation efficiency is one of the possible solutions for the development of radiofrequency (RF) systems [1], for example

  15. MONITORING POWER PLANT EFFICIENCY USING THE MICROWAVE-EXCITED PHOTOACOUSTIC EFFECT TO MEASURE UNBURNED CARBON

    SciTech Connect (OSTI)

    Robert C. Brown; Robert J. Weber; Andrew A. Suby

    2003-01-01T23:59:59.000Z

    Three test instruments are being evaluated to determine the feasibility of using photoacoustic technology for measuring unburned carbon in fly ash. The first test instrument is a single microwave frequency system previously constructed to measure photo-acoustic signals in an off-line configuration. This system was assembled and used to test parameters thought important to photo-acoustic signal output. A standard modulation frequency was chosen based upon signal to noise data gained from experimentation. Sample heterogeneity was tested and found not to be influential. Further testing showed that sample compression and photo-acoustic volume do affect photo-acoustic signal with photoacoustic volume being the most influential. Testing in the fifth quarter focused on microwave power stability. Simultaneously, a second instrument is being constructed based in part on lessons learned with the first instrument, but also expands the capabilities of the first instrument by allowing a spectrum of microwave frequencies to be tested up to 10 GHz. The power amplifiers for this second instrument were completed and tested. Improvements were made to the current leveling loop, which will stabilize the microwave power. This loop is currently in operation with the single frequency cell. Discriminatory measurements are continuing in an attempt to differentiate between magnetic contaminants such as iron and non-magnetic contaminants such as carbon. A short coaxial test fixture was fabricated and tested showing the promise of another microwave based test method for determining carbon content in fly ash. Preliminary design iterations for the third on-line instrument (based on the experiences of the first two instruments) have begun.

  16. Materials for freeform fabrication of GHz tunable dielectric photonic crystals.

    SciTech Connect (OSTI)

    Niehaus, Michael Keith; Lewis, Jennifer A. (University of Illinois, Urbana, IL); Smay, James Earl; Clem, Paul Gilbert; Lin, Shawn-Yu; Cesarano, Joseph, III (,; ); Carroll, James F.

    2003-01-01T23:59:59.000Z

    Photonic crystals are of interest for GHz transmission applications, including rapid switching, GHz filters, and phased-array technology. 3D fabrication by Robocasting enables moldless printing of high solid loading slurries into structures such as the ''woodpile'' structures used to fabricate dielectric photonic band gap crystals. In this work, tunable dielectric materials were developed and printed into woodpile structures via solid freeform fabrication (SFF) toward demonstration of tunable photonic crystals. Barium strontium titanate ceramics possess interesting electrical properties including high permittivity, low loss, and high tunability. This paper discusses the processing route and dielectric characterization of (BaxSr1-XTiO3):MgO ceramic composites, toward fabrication of tunable dielectric photonic band gap crystals.

  17. A precise narrow-beam filter infrared radiometer and its use with lidar in the ARM Program. Progress report, 1 December 1991--31 May 1992

    SciTech Connect (OSTI)

    Platt, C.M.R.

    1992-05-01T23:59:59.000Z

    The first six months of the grant (December 1991--May 1992) have been taken up with the design and specification for the new narrow-beam radiometer. The radiometer will be built and tested at the Division of Atmospheric Research over the next three months. Improved algorithms for obtaining cloud extinction have also been developed. It is proposed during 1993 to use the radiometer in conjunction with a new CSIRO 3-wavelength lidar in the ARM PROBE experiment at Kavieng, New Guinea, which is a test mission under tropical conditions for the ARM CART Tropical West Pacific site, and is part of the TOGA COARE experiment. During the latter part of 1992, the radiometer will be tested thoroughly and tested at the Division of Atmospheric Research, Aspendale.

  18. Uniplanar microwave balanced mixers and amplifiers 

    E-Print Network [OSTI]

    Hsu, Pang-Cheng

    1995-01-01T23:59:59.000Z

    (MMICs). Two new types of uniplanar broadband singly balanced diode mixers are developed. The first mixer exhibits a conversion loss between 6 and 10 dB when the RF is swept from 7 to 10.5 GHz and the LO is 3.5 dBm fixed at 7 GHz. The measured IP3...

  19. Comparison of Historical Satellite-Based Estimates of Solar Radiation Resources with Recent Rotating Shadowband Radiometer Measurements: Preprint

    SciTech Connect (OSTI)

    Myers, D. R.

    2009-03-01T23:59:59.000Z

    The availability of rotating shadow band radiometer measurement data at several new stations provides an opportunity to compare historical satellite-based estimates of solar resources with measurements. We compare mean monthly daily total (MMDT) solar radiation data from eight years of NSRDB and 22 years of NASA hourly global horizontal and direct beam solar estimates with measured data from three stations, collected after the end of the available resource estimates.

  20. 31. 4-GHz flux density measurements of a complete sample of sources from the 5-GHz S5 survey

    SciTech Connect (OSTI)

    Geldzahler, B.J.; Kuehr, H.

    1983-08-01T23:59:59.000Z

    Measurements at 31.4-GHz (9.5-mm) are presented for the complete sample of 66 radio sources with declinations greater than +70/sup 0/ and 5-GHz flux densities greater than 0.5 Jy. About half the sources have the flat radio spectra characteristic of objects with compact components radiating most strongly in the mid-centimeter wavelength range, and about one third show evidence of very compact components (theta< or approx. =0.//0001) radiating at short centimeter wavelengths regardless of morphological type. The median spectral index of all the sources, the quasars alone, and the galaxies alone tends to flatten with increasing frequency for steep spectrum sources, whereas a steepening was found with increasing frequency for the flat spectrum sources.

  1. A MERLIN Study of 6 GHz Excited-state OH & 6.7 GHz Methanol Masers in ON1

    E-Print Network [OSTI]

    J. A. Green; A. M. S. Richards; W. H. T. Vlemmings; P. Diamond; R. J. Cohen

    2007-09-05T23:59:59.000Z

    MERLIN observations of 6.668-GHz methanol and both 6.031- and 6.035-GHz hydroxyl (OH) emission from the massive star-formation region ON1 are presented. These are the first methanol observations made in full polarization using 5 antennas of MERLIN, giving high resolution and sensitivity to extended emission. Maser features are found to lie at the southern edge of the ultra-compact HII region, following the known distribution of ground-state OH masers. The masers cover a region ~1 arcsec in extent, lying perpendicular to the H13CO+ bipolar outflow. Excited-state OH emission demonstrates consistent polarization angles across the strongest linearly polarized features which are parallel to the overall distribution. The linear polarizations vary between 10.0 and 18.5 per cent, with an average polarization angle of -60 deg +/- 28 deg. The strongest 6.668-GHz methanol features provide an upper limit to linear polarization of ~1 per cent. Zeeman splitting of OH shows magnetic fields between -1.1 to -5.8 mG, and a tentative methanol magnetic field strength of -18 mG is measured.

  2. Sub-optical wavelength acoustic wave modulation of integrated photonic resonators at microwave frequencies

    E-Print Network [OSTI]

    Semere Ayalew Tadesse; Mo Li

    2014-10-04T23:59:59.000Z

    Light-sound interactions have long been exploited in various acousto-optic devices based on bulk crystalline materials. Conventionally these devices operate in megahertz frequency range where the acoustic wavelength is much longer than the optical wavelength and a long interaction length is required to attain significant coupling. With nanoscale transducers, acoustic waves with sub-optical wavelengths can now be excited to induce strong acousto-optic coupling in nanophotonic devices. Here we demonstrate microwave frequency surface acoustic wave transducers co-integrated with nanophotonic resonators on piezoelectric aluminum nitride substrates. Acousto-optic modulation of the resonance modes at above 10 GHz with the acoustic wavelength significantly below the optical wavelength is achieved. The phase and modal matching conditions in this scheme are investigated for efficient modulation. The new acousto-optic platform can lead to novel optical devices based on nonlinear Brillouin processes and provides a direct, wideband link between optical and microwave photons for microwave photonics and quantum optomechanics.

  3. Future Directions in the Microwave Cavity Search for Dark Matter Axions

    E-Print Network [OSTI]

    T. M. Shokair; J. Root; K. A. Van Bibber; B. Brubaker; Y. V. Gurevich; S. B. Cahn; S. K. Lamoreaux; M. A. Anil; K. W. Lehnert; B. K. Mitchell; A. Reed; G. Carosi

    2014-05-14T23:59:59.000Z

    The axion is a light pseudoscalar particle which suppresses CP-violating effects in strong interactions and also happens to be an excellent dark matter candidate. Axions constituting the dark matter halo of our galaxy may be detected by their resonant conversion to photons in a microwave cavity permeated by a magnetic field. The current generation of the microwave cavity experiment has demonstrated sensitivity to plausible axion models, and upgrades in progress should achieve the sensitivity required for a definitive search, at least for low mass axions. However, a comprehensive strategy for scanning the entire mass range, from 1-1000 $\\mu$eV, will require significant technological advances to maintain the needed sensitivity at higher frequencies. Such advances could include sub-quantum-limited amplifiers based on squeezed vacuum states, bolometers, and/or superconducting microwave cavities. The Axion Dark Matter eXperiment at High Frequencies (ADMX-HF) represents both a pathfinder for first data in the 20-100 $\\mu$eV range ($\\sim$5-25 GHz), and an innovation test-bed for these concepts.

  4. Method to Calculate Uncertainty Estimate of Measuring Shortwave Solar Irradiance using Thermopile and Semiconductor Solar Radiometers

    SciTech Connect (OSTI)

    Reda, I.

    2011-07-01T23:59:59.000Z

    The uncertainty of measuring solar irradiance is fundamentally important for solar energy and atmospheric science applications. Without an uncertainty statement, the quality of a result, model, or testing method cannot be quantified, the chain of traceability is broken, and confidence cannot be maintained in the measurement. Measurement results are incomplete and meaningless without a statement of the estimated uncertainty with traceability to the International System of Units (SI) or to another internationally recognized standard. This report explains how to use International Guidelines of Uncertainty in Measurement (GUM) to calculate such uncertainty. The report also shows that without appropriate corrections to solar measuring instruments (solar radiometers), the uncertainty of measuring shortwave solar irradiance can exceed 4% using present state-of-the-art pyranometers and 2.7% using present state-of-the-art pyrheliometers. Finally, the report demonstrates that by applying the appropriate corrections, uncertainties may be reduced by at least 50%. The uncertainties, with or without the appropriate corrections might not be compatible with the needs of solar energy and atmospheric science applications; yet, this report may shed some light on the sources of uncertainties and the means to reduce overall uncertainty in measuring solar irradiance.

  5. Densification and thermal gradient evolution of alumina during microwave sintering at 2.45 GHz Daniel ymelkaa

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    is doped by magnesia. This system also allows monitoring of temperature distribution on the surface sample to the conversion of electromagnetic (EM) field energy into heat (rapid heating rates). Reduced sintering.e. by the response of a material to an external electromagnetic field. In the case of dielectric materials

  6. IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 61, NO. 8, AUGUST 2013 2865 A 1540-GHz Frequency Reconfigurable

    E-Print Network [OSTI]

    Akin, Tayfun

    and T. Akin are with the Department of Electrical and Electronics Engineering, Middle East Technical by changing the electrical lengths of the stubs and the connecting transmission lines, while having ideally insertion loss of 3.1, 5, and 8.2 dB and average return loss of 19.3, 15.8, and 13.7 dB at 15, 30, and 40

  7. Monitoring of Precipitable Water Vapor and Cloud Liquid Path from Scanning Microwave Radiometers During the 2003 Cloudiness Inter-Comparison Experiment

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHighandSWPA / SPRA /Ml'.Solar Thermal Solar ThermalJul 13 1 2 3

  8. Microwave assisted hard rock cutting

    DOE Patents [OSTI]

    Lindroth, David P. (Apple Valley, MN); Morrell, Roger J. (Bloomington, MN); Blair, James R. (Inver Grove Heights, MN)

    1991-01-01T23:59:59.000Z

    An apparatus for the sequential fracturing and cutting of subsurface volume of hard rock (102) in the strata (101) of a mining environment (100) by subjecting the volume of rock to a beam (25) of microwave energy to fracture the subsurface volume of rock by differential expansion; and , then bringing the cutting edge (52) of a piece of conventional mining machinery (50) into contact with the fractured rock (102).

  9. Scanning microwave-induced thermoacoustic tomography: Signal, resolution, and contrast

    E-Print Network [OSTI]

    Wang, Lihong

    Scanning microwave-induced thermoacoustic tomography: Signal, resolution, and contrast Geng Ku Scanning thermoacoustic tomography was explored in the microwave region of the electromagnetic spectrum ultrasonic transducer detected the time-resolved thermoacoustic signals. Based on the microwave

  10. Process for microwave sintering boron carbide

    DOE Patents [OSTI]

    Holcombe, Cressie E. (440 Sugarwood Dr., Knoxville, TN 37922); Morrow, Marvin S. (Rte. #3, Box 113, Kingston, TN 37763)

    1993-01-01T23:59:59.000Z

    A method of microwave sintering boron carbide comprises leaching boron carbide powder with an aqueous solution of nitric acid to form a leached boron carbide powder. The leached boron carbide powder is coated with a glassy carbon precursor to form a coated boron carbide powder. The coated boron carbide powder is consolidated in an enclosure of boron nitride particles coated with a layer of glassy carbon within a container for microwave heating to form an enclosed coated boron carbide powder. The enclosed coated boron carbide powder is sintered within the container for microwave heating with microwave energy.

  11. New opportunities in microwave electronics with ferromagnetic nanowires

    SciTech Connect (OSTI)

    Sharma, Monika, E-mail: monikasharma1604@gmail.com; Sharma, Manish; Basu, Ananjan [Centre for Applied Research in Electronics, Indian Institute of Technology, Delhi 110016 (India); Kuanr, Bijoy K. [Special Centre for Nanoscience, Jawaharlal Nehru University, New Delhi 110067 (India)

    2014-05-07T23:59:59.000Z

    A series of monolithic tunable microwave band-stop filters and phase shifters have been designed, fabricated, and characterized on arrays of ferromagnetic nanowires (FMNWs) constituted of Ni, Co, CoFeB, and NiFe alloy embedded in anodic alumina templates (AAO). The aim of the present investigation is to significantly boost the operating frequency of devices in very low applied magnetic field. The stop-band response can cover from 8 to 40?GHz with an applied magnetic field up to 5 kOe using these materials. In addition, we observed a substantial increase in frequency tunability (>110%) for Ni and NiFe alloy based filter. Frequency bandwidth/linewidth can be tuned with the proper choice of magnetic material, broad band for Co nanowires to narrow band for CoFeB nanowires. The amorphous nature of CoFeB reduces linewidth considerably and hence increases resonance absorption. It is also observed that the frequency linewidth (?f) decreases with increasing applied magnetic field. The same filter can be used as a tunable phase shifter. For Ni nanowire based phase shifter, a maximum shift of 75°/cm at 4 kOe was observed.

  12. A 300 GHz collective scattering diagnostic for low temperature plasmas

    SciTech Connect (OSTI)

    Hardin, Robert A.; Scime, Earl E. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506-6315 (United States); Heard, John [Department of Physics, Clarion University, Clarion, Pennsylvania 16214 (United States)

    2008-10-15T23:59:59.000Z

    A compact and portable 300 GHz collective scattering diagnostic employing a homodyne detection scheme has been constructed and installed on the hot helicon experiment (HELIX). Verification of the homodyne detection scheme was accomplished with a rotating grooved aluminum wheel to Doppler shift the interaction beam. The HELIX chamber geometry and collection optics allow measurement of scattering angles ranging from 60 deg. to 90 deg. Artificially driven ion-acoustic waves are also being investigated as a proof-of-principle test for the diagnostic system.

  13. Comment on Quantum teleportation via GHZ-like state

    E-Print Network [OSTI]

    Anindita Banerjee; Kamal Patel; Anirban Pathak

    2010-06-08T23:59:59.000Z

    Recently Yang et al. [Int. J. Theo. Phys. 48 (2009) 516] have shown that an unknown qubit can be teleported by using a particular GHZ-like state as quantum channel. However, there are several errors in the calculation which lead to incorrect conclusions. The errors have been indicated and corrected. It is also noted that their scheme and the independently proposed teleportation scheme of Zhang et al. [Int. J. Theo. Phys. 48 (2009) 3331] uses quantum channel from the same family and any state of that family may be used for teleportation.

  14. Microwave (MW) and Radio Frequency (RF) as Enabling Technologies...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Microwave (MW) and Radio Frequency (RF) as Enabling Technologies for Advanced Manufacturing Microwave (MW) and Radio Frequency (RF) as Enabling Technologies for Advanced...

  15. active microwave medium: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    that silica shell addition through microwave synthesis Park, Jeong Chan; Gilbert, Dustin A; Liu, Kai; Louie, Angelique Y. 2012-01-01 149 MURI High Energy Microwave Sources...

  16. Microwave-excited microplasma thruster with helium and hydrogen propellants

    SciTech Connect (OSTI)

    Takahashi, Takeshi; Takao, Yoshinori; Ichida, Yugo; Eriguchi, Koji; Ono, Kouichi [Department of Aeronautics and Astronautics, Graduate School of Engineering, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501 (Japan)

    2011-06-15T23:59:59.000Z

    Microplasma thruster of electrothermal type has been investigated with feed or propellant gases of He and H{sub 2}. The thruster consisted of an azimuthally symmetric microwave-excited microplasma source 1.5 mm in diameter and 10 mm long with a rod antenna on axis, and a converging-diverging micronozzle 1 mm long with a throat 0.2 mm in diameter. Surface wave-excited plasmas were established by 4.0-GHz microwaves at powers of {<=} 6 W, with the source pressure in the range 0.5-12 kPa at flow rates of 2-70 sccm. The microplasma generation, micronozzle flow, and thrust performance with He were numerically analyzed by using a two-dimensional fluid model, coupled with an electromagnetic model for microwaves interacting with plasmas in the source region. In experiments, the plasma electron density and gas temperature in the microplasma source were measured at around the top of the microwave antenna, or just upstream of the micronozzle inlet, by optical emission spectroscopy with a small amount of additive gases of H{sub 2} and N{sub 2}. In the case of He propellant, the Stark broadening of H Balmer-{beta} line and the vibronic spectrum of N{sub 2} 2nd positive (0, 2) band indicated that the electron density was in the range (2-5)x10{sup 19}m{sup -3} and the gas or rotational temperature was in the range 600-700 K. The thrust performance was also measured by using a target-type microthrust stand, giving a thrust in the range 0.04-0.51 mN, a specific impulse in the range 150-270 s, and a thrust efficiency in the range 2%-12%. These experimental results were consistent with those of numerical analysis, depending on microwave power and gas flow rate. Similar plasma characteristics and thrust performance were obtained with H{sub 2} propellant, where the specific impulse of {<=} 450 s was more than 1.5 times higher than that with He, owing to a difference in mass between He and H{sub 2}. A comparison with previous studies with Ar propellant [T. Takahashi et al., Phys. Plasmas 16, 083505 (2009)] indicated that in the presence as well as absence of plasma discharge, the specific impulse was enhanced by more than 3-5 times with light-mass propellants He and H{sub 2} as has been known for large-scale propulsion systems. Thus, it follows that in the microplasma thruster of electrothermal type, the high diffusivity and thermal conductivity of He and H{sub 2} in the microplasma source of high surface-to-volume ratios do not lead to a deterioration of the thrust performance, primarily owing to a more significant thermal energy gain due to elastic collisions between electrons and heavy particles in He and H{sub 2}.

  17. The R/V Discoverer cruise to Manus Island. The BNL Portable Radiometer Package (PRP) evaluation

    SciTech Connect (OSTI)

    Reynolds, R.M.; Smith, S.

    1996-05-24T23:59:59.000Z

    Brookhaven National Laboratory installed and operated a Portable Radiation Package (PRP) on the NOAA ship R/V DISCOVERER as part of the Combined Sensor Program cruise in the Tropical Western Pacific Ocean. The DISCOVERER transported a collection of radiation and atmospheric instrumentation to positions offshore of manus Island to compare cloud and radiation fields to like instruments measured from a station on the island. The ship sailed NW from Pago Pago, American Samoa, on 14 March 1996 to a latitude of 1{degree}S then due West until it approached manus Island (2{degree}S and 148{degree}E) on approximately 7 April. The ship then turned SW and approached Manus Island in three steps. This route was reversed during the ship`s return to Hawaii. The PRP package is a compact low-power integration of simple sensors that measure long- and short-wave irradiance from moving platforms. A rapid rotating shadowband radiometer that is designed to provide good estimates of diffuse (sky) radiation even from moving buoys or ships was being evaluated. The PRP provided the only means of making diffuse (sky) radiation measurements from the ship. The CSP cruise provided an excellent opportunity to intercompare the PRP with other like instruments in the TWP locale. The unit was located on the starboard flying bridge which was fully exposed to direct sunlight during the ship`s westward transit. When the ship was at its closest approach to manus, the PRP was moved to the island where careful intercomparison with the Manus instrumentation was conducted.

  18. Impedance Mismatch study between the Microwave Generator and the PUPR Plasma Machine

    SciTech Connect (OSTI)

    Gaudier, Jorge R.; Castellanos, Ligeia; Encarnacion, Kabir; Zavala, Natyaliz; Rivera, Ramon; Farahat, Nader; Leal, Edberto [Polytechnic University of Puerto Rico, San Juan, 00919-2017 (Puerto Rico)

    2006-12-04T23:59:59.000Z

    Impedance mismatch inside the connection from the microwave power generator to the plasma machine is studied. A magnetron power generator transmits microwaves of 2.45 GHz and variable power from 50W to 5000W, through a flexible rectangular waveguide to heat plasma inside a Mirror Cusp devise located at the Polytechnic University of Puerto Rico. Before the production of plasma, the residual gas of the devise must be extracted by a vacuum system (5Torr or better), then Argon gas is injected to the machine. The microwaves heat the Argon ions to initiate ionization and plasma is produced. A dielectric wall is used inside the rectangular waveguide to isolate the plasma machine and maintain vacuum. Even though the dielectric will not block the wave propagation, some absorption of microwaves will occur. This absorption will cause reflection, reducing the efficiency of the power transfer. Typically a thin layer of Teflon is used, but measurements using this dielectric show a significant reflection of power back to the generator. Due to the high-power nature of the generator (5KW), this mismatch is not desirable. An electromagnetic field solver based on the Finite Difference Time Domain Method(FDTD) is used to model the rectangular waveguide connection. The characteristic impedance of the simulation is compared with the analytical formula expression and a good agreement is obtain. Furthermore the Teflon-loaded guide is modeled using the above program and the input impedance is computed. The reflection coefficient is calculated based on the transmission line theory with the characteristic and input impedances. Based on the simulation results it is possible to optimize the thickness, shape and dielectric constant of the material, in order to seal the connection with a better match.

  19. A Global 86GHz VLBI Survey of Compact Radio Sources

    E-Print Network [OSTI]

    Sang-Sung Lee; Andrei P. Lobanov; Thomas P. Krichbaum; Arno Witzel; J. Anton Zensus; Michael Bremer; Albert Greve; Michael Grewing

    2008-03-28T23:59:59.000Z

    We present results from a large 86GHz global VLBI survey of compact radio sources. The main goal of the survey is to increase by factors of 3--5 the total number of objects accessible for future 3-mm VLBI imaging. The survey observations reach the baseline sensitivity of 0.1Jy and image sensitivity of better than 10 mJy/beam. The total of 127 compact radio sources have been observed. The observations have yielded images for 109 sources, extending the database of the sources imaged at 86GHz with VLBI observation by a factor of 5, and only 6 sources have not been detected. The remaining 12 objects have been detected but could not be imaged due to insufficient closure phase information. Radio galaxies are less compact than quasars and BL Lacs on sub-milliarcsecond scale. Flux densities and sizes of core and jet components of all imaged sources have been estimated using Gaussian model fitting. From these measurements, brightness temperatures have been calculated, taking into account resolution limits of the data. The cores of 70% of the imaged sources are resolved. The core brightness temperatures of the sources peak at $\\sim 10^{11}$ K and only 1% have brightness temperatures higher than $10^{12}$ K. Cores of Intraday Variable (IDV) sources are smaller in angular size than non-IDV sources, and so yield higher brightness temperatures.

  20. A precise passive narrow-beam filter infrared radiometer and its use with LIDAR in the ARM program. Progress report, 1 June 1992--31 May 1993

    SciTech Connect (OSTI)

    Platt, C.M.R.

    1993-05-01T23:59:59.000Z

    The work done divides conveniently into two parts. First, the completion of the design and manufacture of the new narrow-beam radiometer, which occupied the period of July to December, 1992. The second part of the report concerns participation of the CSIRO Division of Atmospheric Research (DAR) Lidar/radiometer team in the ARM PROBE experiment at Kavieng, New Ireland, Papua New Guinea as part of the international TOGA COARE experiment. The DAR team participated for about one month from mid-January. The PROBE experiment allowed the new radiometer to be tested under field conditions, a test which was very successful, with very few teething problems. It is proposed during the rest of 1993 and during 1994 to make further tests with the radiometer and particularly to look at using a stirling cycle liquid nitrogen detector to obviate the need for supplies of liquid nitrogen. It is proposed further during 1994 to carry out a thorough analysis of the PROBE data and collaborate with other US PROBE participants in studying and interpreting the observations as a whole. Some further work with the new ARM radiometer will be done during the CSIRO SOCEX experiment.

  1. Microwave-triggered laser switch

    DOE Patents [OSTI]

    Piltch, Martin S. (Los Alamos, NM)

    1984-01-01T23:59:59.000Z

    A high-repetition rate switch for delivering short duration, high-power electrical pulses from a pulsed-charged dc power supply. The present invention utilizes a microwave-generating device such as a magnetron that is capable of producing high-power pulses at high-pulse repetition rates and fast-pulse risetimes for long periods with high reliability. The rail-gap electrodes provide a large surface area that reduces induction effects and minimizes electrode erosion. Additionally, breakdown is initiated in a continuous geometric fashion that also increases operating lifetime of the device.

  2. Microwave Meals in a Hurry.

    E-Print Network [OSTI]

    Haggard, Marilyn A.

    1981-01-01T23:59:59.000Z

    of time to prepare complete meals. Select dishes that are family favorites and use tested recipes . Learning to adapt recipes for microwave cooking comes. later with experience. In general, advance meal planning is the key to getting the most out.... For example, whole carrots stay hot longer than sliced carrots. Cooking and then serving food in the same dish extends holding time. So does wrapping or cov ering the food in plastic wrap or foil, or covering it with a lid. Cook foods with a long holding...

  3. Microwave-triggered laser switch

    DOE Patents [OSTI]

    Piltch, M.S.

    1982-05-19T23:59:59.000Z

    A high-repetition rate switch is described for delivering short duration, high-powered electrical pulses from a pulsed-charged dc power supply. The present invention utilizes a microwave-generating device such as a magnetron that is capable of producing high-power pulses at high-pulse repetition rates and fast-pulse risetimes for long periods with high reliability. The rail-gap electrodes provide a large surface area that reduces induction effects and minimizes electrode erosion. Additionally, breakdown is initiated in a continuous geometric fashion that also increases operating lifetime of the device.

  4. Microwave cavity search for paraphotons

    SciTech Connect (OSTI)

    Povey, Rhys; Hartnett, John; Tobar, Michael [School of Physics, University of Western Australia, 35 Stirling Hwy, Crawley 6009 WA (Australia)

    2010-06-15T23:59:59.000Z

    In this proceeding we report the first results of a microwave cavity search for hidden sector photons. Using a pair of isolated resonant cavities we look for 'light shining through a wall' from photon--hidden sector photon oscillations. Our prototype experiment consists of two cylindrical, copper cavities stacked axially inside a single vacuum chamber. At a hidden sector photon mass of 39.58 mueV we place an upper limit on the kinetic mixing parameter chi at 7.8x10{sup -6}. Whilst this result is inside already established limits our experiment has great scope for improvement.

  5. Microwave-enhanced chemical processes

    DOE Patents [OSTI]

    Varma, R.

    1990-06-19T23:59:59.000Z

    A process is disclosed for the disposal of toxic wastes including chlorinated hydrocarbons, comprising, establishing a bed of non-metallic particulates having a high dielectric loss factor. Intimate contact of the particulates and the toxic wastes at a temperature in excess of about 400 C in the presence of microwave radiation for a time sufficient breaks the hydrocarbon chlorine bonds. Detoxification values in excess of 80 are provided and further detoxification of the bed is followed by additional disposal of toxic wastes. 1 figure.

  6. Soil moisture modeling and scaling using passive microwave remote sensing 

    E-Print Network [OSTI]

    Das, Narendra N.

    2007-04-25T23:59:59.000Z

    across spatial scales; accounting uncertainties in forcing data; and preserving interactions for spatially correlated pixels. The second study focused on spatial scaling properties of the Polarimetric Scanning Radiometer (PSR)-based remotely sensed...

  7. Tandem microwave waste remediation and decontamination system

    DOE Patents [OSTI]

    Wicks, George G. (North Aiken, SC); Clark, David E. (Gainesville, FL); Schulz, Rebecca L. (Gainesville, FL)

    1999-01-01T23:59:59.000Z

    The invention discloses a tandem microwave system consisting of a primary chamber in which microwave energy is used for the controlled combustion of materials. A second chamber is used to further treat the off-gases from the primary chamber by passage through a susceptor matrix subjected to additional microwave energy. The direct microwave radiation and elevated temperatures provide for significant reductions in the qualitative and quantitative emissions of the treated off gases. The tandem microwave system can be utilized for disinfecting wastes, sterilizing materials, and/or modifying the form of wastes to solidify organic or inorganic materials. The simple design allows on-site treatment of waste by small volume waste generators.

  8. Electrodeless lamp energized by microwave energy

    SciTech Connect (OSTI)

    Ervin, R.M.; Perret, J.

    1990-01-16T23:59:59.000Z

    This patent describes an electrodeless lamp. It comprises: a microwave cavity; a source of microwaves in communication with the cavity; a lamp envelope containing a plasma-forming medium mounted within the microwave cavity; a gas manifold for feeding gas to at least one gas passageway for directing a stream of gas to the outer surface of the envelope; a gas leak passageway leading from the gas manifold; a conductive mesh assembly for retaining microwaves within the cavity and permitting light to be emitted from the cavity. The assembly including gas flow blocking means for preventing the flow of gas through the gas leak passageway when the screen is in place in the lamp; and means for shutting off the source of microwaves when the gas pressure in the manifold drops below a predetermined value.

  9. Microwave generated plasma light source apparatus

    SciTech Connect (OSTI)

    Yoshizawa, K.; Ito, H.; Kodama, H.; Komura, H.; Minowa, Y.

    1985-02-05T23:59:59.000Z

    A microwave generated plasma light source including a microwave generator, a microwave cavity having a light reflecting member forming at least a portion of the cavity, and a member transparent to light and opaque to microwaves disposed across an opening of the cavity opposite the feeding opening through which the microwave generator is coupled. An electrodeless discharge bulb is disposed at a position in the cavity such that the cavity operates as a resonant cavity at least when the bulb is emitting light. In the bulb is encapsulated at least one discharge light emissive substance. The bulb has a shape and is sufficiently small that the bulb acts substantially as a point light source.

  10. Microwave drying of ferric oxide pellets

    SciTech Connect (OSTI)

    Pickles, C.A.; Xia, D.K. [Queens` Univ., Kingston, Ontario (Canada). Dept. of Materials and Metallurgical Engineering

    1997-12-31T23:59:59.000Z

    The application of microwave energy for the drying of ferric oxide pellets has been investigated and evaluated. It is shown that the microwave drying rates are much higher than those observed in the conventional process. Also there is some potential for improved quality of the product. As a stand-alone technology it is unlikely that microwave drying would be economical for pellets due to the low cost of conventional fuels. However, based on an understanding of the drying mechanisms in the conventional process and in the microwave process, it is shown that microwave-assisted drying offers considerable potential. In this hybrid process, the advantages of the two drying techniques are combined to provide an improved drying process.

  11. Synthesis of macrocyclic polyaminocarboxylates and their use for preparing stable radiometal antibody immunoconjugates for therapy, SPECT and PET imaging

    DOE Patents [OSTI]

    Mease, R.C.; Mausner, L.F.; Srivastava, S.C.

    1995-06-27T23:59:59.000Z

    A simple method for the synthesis of 1,4,7,10-tetraazacyclododecane N,N{prime}N{double_prime},N{prime}{double_prime}-tetraacetic acid and 1,4,8,11-tetraazacyclotetradecane N,N{prime},N{double_prime},N{prime}{double_prime}-tetraacetic acid involves cyanomethylating 1,4,7,10-tetraazacyclododecane or 1,4,8,11-tetraazacyclotetradecane to form a tetranitrile and hydrolyzing the tetranitrile. These macrocyclic compounds are functionalized through one of the carboxylates and then conjugated to various biological molecules including monoclonal antibodies. The resulting conjugated molecules are labeled with radiometals for SPECT and PET imaging and for radiotherapy. 4 figs.

  12. Synthesis of macrocyclic polyaminocarboxylates and their use for preparing stable radiometal antibody immunoconjugates for therapy, spect and pet imaging

    DOE Patents [OSTI]

    Mease, Ronnie C. (Fairfax, VA); Mausner, Leonard F. (Stony Brook, NY); Srivastava, Suresh C. (Setauket, NY)

    1995-06-27T23:59:59.000Z

    A simple method for the synthesis of 1,4,7,10-tetraazacyclododecane N,N'N",N'"-tetraacetic acid and 1,4,8,11-tetraazacyclotetradecane N,N',N",N'"-tetraacetic acid involves cyanomethylating 1,4,7,10-tetraazacyclododecane or 1,4,8,11-tetraazacyclotetradecane to form a tetranitrile and hydrolyzing the tetranitrile. These macrocyclic compounds are functionalized through one of the carboxylates and then conjugated to various biological molecules including monoclonal antibodies. The resulting conjugated molecules are labeled with radiometals for SPECT and PET imaging and for radiotherapy.

  13. Results of First Outdoor Comparison Between Absolute Cavity Pyrgeometer (ACP) and Infrared Integrating Sphere (IRIS) Radiometer at PMOD (Presentation)

    SciTech Connect (OSTI)

    Reda, I.; Grobner, J.; Wacker, S.; Stoffel, T.

    2013-03-01T23:59:59.000Z

    The ACP and IRIS are developed to establish a world reference for calibrating pyrgeometers with traceability to SI units. The two radiometers are unwindowed with negligible spectral dependence, and traceable to SI units through the temperature scale (ITS-90). The first outdoor comparison between the two designs was held from January 28 to February 8, 2013 at the Physikalisch-Metorologisches Observatorium Davos (PMOD). The difference between the irradiance measured by ACP and that of IRIS was within 1 W/m2. A difference of 5 W/m2 was observed between the irradiance measured by ACP&IRIS and that of the interim World Infrared Standard Group (WISG).

  14. Yb:(YLa){sub 2}O{sub 3} laser ceramics produced by microwave sintering

    SciTech Connect (OSTI)

    Balabanov, S S; Bykov, Yu V; Egorov, S V; Eremeev, A G; Gavrishchuk, E M; Khazanov, Efim A; Mukhin, I B; Palashov, O V; Permin, D A; Zelenogorskii, V V

    2013-04-30T23:59:59.000Z

    The possibility of using microwave heating for sintering of optical oxide ceramics and the advantages of this method are considered. Sintering of Yb{sub 0.1}:(YLa){sub 1.9}O{sub 3} ceramics by heating with 24-GHz radiation is studied. The compacts for sintering are prepared from nanosized powders obtained by high-temperature synthesis from acetate-nitrates of rare-earth metals. The effect of addition of lanthanum oxide and of the uniaxial pressing conditions on the microstructure and optical transmission of ceramics is studied. Lasing at a wavelength of 1030 nm with an efficiency of 7.5 % is achieved in ceramic samples of the (Yb{sub 0.05}Y{sub 0.1}La{sub 0.85}){sub 2}O{sub 3} composition under pumping by a laser diode at a wavelength of 940 nm. (extreme light fields and their applications)

  15. advanced microwave processing: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    for 148 GHz (90 GHz) only 3% (4%) of halos have thei... Sehgal, Neelima; Das, Sudeep; Hernandez-Monteagudo, Carlos; Huffenberger, Kevin; Lin, Yen-Ting; Ostriker, Jeremiah P; Trac,...

  16. A microwave resonator for limiting depth sensitivity for electron paramagnetic resonance spectroscopy of surfaces

    SciTech Connect (OSTI)

    Sidabras, Jason W.; Varanasi, Shiv K.; Hyde, James S. [Department of Biophysics, Medical College of Wisconsin, Milwaukee, Wisconsin 53211 (United States); Mett, Richard R. [Department of Biophysics, Medical College of Wisconsin, Milwaukee, Wisconsin 53211 (United States); Department of Physics and Chemistry, Milwaukee School of Engineering, Milwaukee, Wisconsin 53202 (United States); Swarts, Steven G. [Department of Radiation Oncology, University of Florida, Gainesville, Florida, 32610 (United States); Swartz, Harold M. [Department of Radiology, Geisel Medical School at Dartmouth, Hanover, New Hampshire 03755 (United States)

    2014-10-15T23:59:59.000Z

    A microwave Surface Resonator Array (SRA) structure is described for use in Electron Paramagnetic Resonance (EPR) spectroscopy. The SRA has a series of anti-parallel transmission line modes that provides a region of sensitivity equal to the cross-sectional area times its depth sensitivity, which is approximately half the distance between the transmission line centers. It is shown that the quarter-wave twin-lead transmission line can be a useful element for design of microwave resonators at frequencies as high as 10 GHz. The SRA geometry is presented as a novel resonator for use in surface spectroscopy where the region of interest is either surrounded by lossy material, or the spectroscopist wishes to minimize signal from surrounding materials. One such application is in vivo spectroscopy of human finger-nails at X-band (9.5 GHz) to measure ionizing radiation dosages. In order to reduce losses associated with tissues beneath the nail that yield no EPR signal, the SRA structure is designed to limit depth sensitivity to the thickness of the fingernail. Another application, due to the resonator geometry and limited depth penetration, is surface spectroscopy in coating or material science. To test this application, a spectrum of 1.44 ?M of Mg{sup 2+} doped polystyrene 1.1 mm thick on an aluminum surface is obtained. Modeling, design, and simulations were performed using Wolfram Mathematica (Champaign, IL; v. 9.0) and Ansys High Frequency Structure Simulator (HFSS; Canonsburg, PA; v. 15.0). A micro-strip coupling circuit is designed to suppress unwanted modes and provide a balanced impedance transformation to a 50 ? coaxial input. Agreement between simulated and experimental results is shown.

  17. Design and optimization of a 200 GHz SiGe HBT collector profile by TCAD

    E-Print Network [OSTI]

    Rieh, Jae-Sung

    Design and optimization of a 200 GHz SiGe HBT collector profile by TCAD Andreas D. Strickera A novel simulation assisted investigation was used to obtain the optimum collector design of a 200 GHz; BJT; Collector doping profile; TCAD; Design methodology 1. Introduction The continuing trend toward

  18. 37 GHz METHANOL MASERS : HORSEMEN OF THE APOCALYPSE FOR THE CLASS II METHANOL MASER PHASE?

    SciTech Connect (OSTI)

    Ellingsen, S. P.; Breen, S. L. [School of Mathematics and Physics, University of Tasmania, Private Bag 37, Hobart, TAS 7001 (Australia); Sobolev, A. M. [Astronomical Observatory, Ural Federal University, Lenin avenue 51, 620000 Ekaterinburg (Russian Federation); Voronkov, M. A.; Caswell, J. L. [CSIRO Astronomy and Space Science, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710 (Australia); Lo, N., E-mail: Simon.Ellingsen@utas.edu.au [Departamento de Astronomia, Universidad de Chile, Camino El Observatorio 1515, Las Condes, Santiago, Casilla 36-D (Chile)

    2011-12-01T23:59:59.000Z

    We report the results of a search for class II methanol masers at 37.7, 38.3, and 38.5 GHz toward a sample of 70 high-mass star formation regions. We primarily searched toward regions known to show emission either from the 107 GHz class II methanol maser transition, or from the 6.035 GHz excited OH transition. We detected maser emission from 13 sources in the 37.7 GHz transition, eight of these being new detections. We detected maser emission from three sources in the 38 GHz transitions, one of which is a new detection. We find that 37.7 GHz methanol masers are only associated with the most luminous 6.7 and 12.2 GHz methanol maser sources, which in turn are hypothesized to be the oldest class II methanol sources. We suggest that the 37.7 GHz methanol masers are associated with a brief evolutionary phase (of 1000-4000 years) prior to the cessation of class II methanol maser activity in the associated high-mass star formation region.

  19. Hanbury BrownTwiss Correlations to Probe the Population Statistics of GHz Photons Emitted by Conductors

    E-Print Network [OSTI]

    Plaçais, Bernard

    Hanbury Brown­Twiss Correlations to Probe the Population Statistics of GHz Photons Emitted of GHz photons in quantum circuits, using Hanbury Brown and Twiss correlations. The super The seminal experiment of Hanbury Brown and Twiss (HBT) [1], consisted in two detectors correlating the power

  20. THE CELESTIAL REFERENCE FRAME AT 24 AND 43 GHz. I. ASTROMETRY

    SciTech Connect (OSTI)

    Lanyi, G. E.; Jacobs, C. S.; Naudet, C. J.; Sovers, O. J.; Zhang, L. D. [Jet Propulsion Laboratory, Caltech, 4800 Oak Grove Dr., Pasadena, CA 91109 (United States); Boboltz, D. A.; Fey, A. L. [U.S. Naval Observatory, 3450 Massachusetts Ave., NW, Washington, DC 20392-5420 (United States); Charlot, P. [Universite de Bordeaux, Observatoire Aquitain des Sciences de l'Univers, BP 89, 33271 Floirac Cedex (France); Fomalont, E. B. [National Radio Astronomy Observatory, 520 Edgemont Rd., Charlottesville, VA 22903 (United States); Geldzahler, B. J. [National Aeronautics and Space Administration, 300 E. St., SW, Washington, DC 20546 (United States); Gordon, D. [NVI Inc./NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Ma, C. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Romney, J. D. [National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801 (United States)

    2010-05-15T23:59:59.000Z

    We present astrometric results for compact extragalactic objects observed with the Very Long Baseline Array at radio frequencies of 24 and 43 GHz. Data were obtained from ten 24 hr observing sessions made over a five-year period. These observations were motivated by the need to extend the International Celestial Reference Frame (ICRF) to higher radio frequencies to enable improved deep space navigation after 2016 and to improve state-of-the-art astrometry. Source coordinates for 268 sources were estimated at 24 GHz and for 131 sources at 43 GHz. The median formal uncertainties of right ascension and declination at 24 GHz are 0.08 and 0.15 mas, respectively. Median formal uncertainties at 43 GHz are 0.20 and 0.35 mas, respectively. Weighted root-mean-square differences between the 24 and 43 GHz positions and astrometric positions based on simultaneous 2.3 and 8.4 GHz Very Long Baseline Interferometry observations, such as the ICRF, are less than about 0.3 mas in both coordinates. With observations over five years we have achieved a precision at 24 GHz approaching that of the ICRF but unaccounted systematic errors limit the overall accuracy of the catalogs.

  1. 108 GHz passive mode locking of a multiple quantum well semiconductor laser with an intracavity absorber

    SciTech Connect (OSTI)

    Sanders, S.; Eng, L.; Paslaski, J.; Yariv, A. (Department of Applied Physics 128-95, California Institute of Technology, Pasadena, California 91125 (US))

    1990-01-22T23:59:59.000Z

    A two-section multiple quantum well laser is passively mode locked without an external cavity at {similar to}108 GHz. The pulse widths average 2.4 ps and have a time-bandwidth product of 1.1. Self-pulsations at frequencies up to 8 GHz are also observed.

  2. 6.7 GHZ METHANOL MASERS: PROPERTIES, ASSOCIATIONS AND TRACERS OF GALACTIC

    E-Print Network [OSTI]

    Richardson Jr., James E.

    6.7 GHZ METHANOL MASERS: PROPERTIES, ASSOCIATIONS AND TRACERS OF GALACTIC STRUCTURE A Dissertation Jagadheep Dhanasekara Pandian ALL RIGHTS RESERVED #12;6.7 GHZ METHANOL MASERS: PROPERTIES, ASSOCIATIONS transition of methanol is the strongest of methanol masers, and is the second strongest maser transition ever

  3. A 60GHz, 13dBm Fully Integrated 65nm RF-CMOS Power Amplifier

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    simulation. A. Transistor Layout Caracterisation The size of the transistor depends on the maximum powerA 60GHz, 13dBm Fully Integrated 65nm RF-CMOS Power Amplifier Sofiane Aloui, Eric Kerhervé IMS-CNRS University of Toulouse Toulouse, France plana@laas.fr Abstract--A 65nm CMOS, 60GHz fully integrated power

  4. Results of Second Outdoor Comparison Between Absolute Cavity Pyrgeometer (ACP) and Infrared Integrating Sphere (IRIS) Radiometer at PMOD (Presentation)

    SciTech Connect (OSTI)

    Reda, I.; Grobner, J.; Wacker, S.

    2014-01-01T23:59:59.000Z

    The Absolute Cavity Pyrgeometer (ACP) and InfraRed Integrating Sphere radiometer (IRIS) are developed to establish a world reference for calibrating pyrgeometers with traceability to SI units. The two radiometers are un-windowed with negligible spectral dependence, and traceable to SI units through the temperature scale (ITS-90). The second outdoor comparison between the two designs was held from September 30 to October 11, 2013 at the Physikalisch-Metorologisches Observatorium Davos (PMOD). The difference between the irradiance measured by ACP and that of the IRIS was within 1 W/m2 (3 IRISs: PMOD + Australia + Germany). From the first and second comparisons, a difference of 4-6 W/m2 was observed between the irradiance measured by ACP&IRIS and that of the interim World Infrared Standard Group (WISG). This presentation includes results from the first and second comparison in an effort to establish the world reference for pyrgeometer calibrations, a key deliverable for the World Meteorological Organization (WMO), and the DOE-ASR.

  5. Dependence of ion beam current on position of mobile plate tuner in multi-frequencies microwaves electron cyclotron resonance ion source

    SciTech Connect (OSTI)

    Kurisu, Yosuke; Kiriyama, Ryutaro; Takenaka, Tomoya; Nozaki, Dai; Sato, Fuminobu; Kato, Yushi; Iida, Toshiyuki [Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2012-02-15T23:59:59.000Z

    We are constructing a tandem-type electron cyclotron resonance ion source (ECRIS). The first stage of this can supply 2.45 GHz and 11-13 GHz microwaves to plasma chamber individually and simultaneously. We optimize the beam current I{sub FC} by the mobile plate tuner. The I{sub FC} is affected by the position of the mobile plate tuner in the chamber as like a circular cavity resonator. We aim to clarify the relation between the I{sub FC} and the ion saturation current in the ECRIS against the position of the mobile plate tuner. We obtained the result that the variation of the plasma density contributes largely to the variation of the I{sub FC} when we change the position of the mobile plate tuner.

  6. EXPANDED VERY LARGE ARRAY DETECTION OF 36.2 GHz CLASS I METHANOL MASERS IN SAGITTARIUS A

    E-Print Network [OSTI]

    Sjouwerman, Loránt O.

    We report on the interferometric detection of 36.2 GHz Class I methanol emission with the new 27-40 GHz Ka-band receivers available on the Expanded Very Large Array (EVLA). The brightness temperatures of the interferometric ...

  7. Modulated microwave microscopy and probes used therewith

    DOE Patents [OSTI]

    Lai, Keji; Kelly, Michael; Shen, Zhi-Xun

    2012-09-11T23:59:59.000Z

    A microwave microscope including a probe tip electrode vertically positionable over a sample and projecting downwardly from the end of a cantilever. A transmission line connecting the tip electrode to the electronic control system extends along the cantilever and is separated from a ground plane at the bottom of the cantilever by a dielectric layer. The probe tip may be vertically tapped near or at the sample surface at a low frequency and the microwave signal reflected from the tip/sample interaction is demodulated at the low frequency. Alternatively, a low-frequency electrical signal is also a non-linear electrical element associated with the probe tip to non-linearly interact with the applied microwave signal and the reflected non-linear microwave signal is detected at the low frequency. The non-linear element may be semiconductor junction formed near the apex of the probe tip or be an FET formed at the base of a semiconducting tip.

  8. Chemical vapor infiltration using microwave energy

    DOE Patents [OSTI]

    Devlin, David J. (Los Alamos, NM); Currier, Robert P. (Los Alamos, NM); Laia, Jr., Joseph R. (Los Alamos, NM); Barbero, Robert S. (Santa Cruz, NM)

    1993-01-01T23:59:59.000Z

    A method for producing reinforced ceramic composite articles by means of chemical vapor infiltration and deposition in which an inverted temperature gradient is utilized. Microwave energy is the source of heat for the process.

  9. Continuous, real time microwave plasma element sensor

    DOE Patents [OSTI]

    Woskov, Paul P. (4 Ledgewood Dr., Bedford, MA 01730); Smatlak, Donna L. (10 Village Hill Rd., Belmont, MA 02178); Cohn, Daniel R. (26 Walnut Hill Rd., Chestnut Hill, MA 02167); Wittle, J. Kenneth (1740 Conestoga Rd., Chester Springs, PA 19425); Titus, Charles H. (323 Echo Valley La., Newton Square, PA 19072); Surma, Jeffrey E. (806 Brian La., Kennewick, WA 99337)

    1995-01-01T23:59:59.000Z

    Microwave-induced plasma for continuous, real time trace element monitoring under harsh and variable conditions. The sensor includes a source of high power microwave energy and a shorted waveguide made of a microwave conductive, refractory material communicating with the source of the microwave energy to generate a plasma. The high power waveguide is constructed to be robust in a hot, hostile environment. It includes an aperture for the passage of gases to be analyzed and a spectrometer is connected to receive light from the plasma. Provision is made for real time in situ calibration. The spectrometer disperses the light, which is then analyzed by a computer. The sensor is capable of making continuous, real time quantitative measurements of desired elements, such as the heavy metals lead and mercury.

  10. Continuous, real time microwave plasma element sensor

    DOE Patents [OSTI]

    Woskov, P.P.; Smatlak, D.L.; Cohn, D.R.; Wittle, J.K.; Titus, C.H.; Surma, J.E.

    1995-12-26T23:59:59.000Z

    Microwave-induced plasma is described for continuous, real time trace element monitoring under harsh and variable conditions. The sensor includes a source of high power microwave energy and a shorted waveguide made of a microwave conductive, refractory material communicating with the source of the microwave energy to generate a plasma. The high power waveguide is constructed to be robust in a hot, hostile environment. It includes an aperture for the passage of gases to be analyzed and a spectrometer is connected to receive light from the plasma. Provision is made for real time in situ calibration. The spectrometer disperses the light, which is then analyzed by a computer. The sensor is capable of making continuous, real time quantitative measurements of desired elements, such as the heavy metals lead and mercury. 3 figs.

  11. Detection of contraband using microwave radiation

    DOE Patents [OSTI]

    Toth, Richard P. (Albuquerque, NM); Loubriel, Guillermo M. (Albuquerque, NM); Bacon, Larry D. (Albuquerque, NM); Watson, Robert D. (Tijeras, NM)

    2002-01-01T23:59:59.000Z

    The present invention relates to a method and system for using microwave radiation to detect contraband hidden inside of a non-metallic container, such as a pneumatic vehicle tire. The method relies on the attenuation, retardation, time delay, or phase shift of microwave radiation as it passes through the container plus the contraband. The method is non-invasive, non-destructive, low power, and does not require physical contact with the container.

  12. Continuous microwave regeneration apparatus for absorption media

    DOE Patents [OSTI]

    Smith, Douglas D. (Knoxville, TN)

    1999-01-01T23:59:59.000Z

    A method and apparatus for continuously drying and regenerating ceramic beads for use in process gas moisture drying operations such as glove boxes. A microwave energy source is coupled to a process chamber to internally heat the ceramic beads and vaporize moisture contained therein. In a preferred embodiment, the moisture laden ceramic beads are conveyed toward the microwave source by a screw mechanism. The regenerated beads flow down outside of the screw mechanism and are available to absorb additional moisture.

  13. High Precision Noise Measurements at Microwave Frequencies

    SciTech Connect (OSTI)

    Ivanov, Eugene; Tobar, Michael [School of Physics, University of Western Australia, 35 Stirling Hwy., Crawley, 6009, WA (Australia)

    2009-04-23T23:59:59.000Z

    We describe microwave noise measurement system capable of detecting the phase fluctuations of rms amplitude of 2{center_dot}10{sup -11} rad/{radical}(Hz). Such resolution allows the study of intrinsic fluctuations in various microwave components and materials, as well as precise tests of fundamental physics. Employing this system we discovered a previously unknown phenomenon of down-conversion of pump oscillator phase noise into the low-frequency voltage fluctuations.

  14. Wide-open, high-resolution microwave/millimeter-wave Doppler frequency shift estimation using photonics technology

    E-Print Network [OSTI]

    Zou, Xihua; Lu, Bing; Pan, Wei; Yan, Lianshan; Shao, Liyang

    2014-01-01T23:59:59.000Z

    Today, wide-open, high-resolution Doppler frequency shift (DFS) estimation is essential for radar, microwave/millimeter-wave, and communication systems. Using photonics technology, an effective approach is proposed and experimentally demonstrated, providing a high-resolution and frequency-independent solution. In the approach consisting of two cascaded opto-electronic modulators, DFS between the transmitted microwave/ millimeter-wave signal and the received echo signal is mapped into a doubled spacing between two target optical sidebands. Subsequently, the DFS is then estimated through the spectrum analysis of a generated low-frequency electrical signal, with an improved resolution by a factor of 2. In experiments, DFSs from -90 to 90 KHz are successfully estimated for microwave/millimeter-wave signals at 10, 15, and 30 GHz, where estimation errors keep lower than +/- 5e-10 Hz. For radial velocity measurement, these results reveal a range from 0 to 900 m/s (0 to 450 m/s) and a resolution of 1e-11 m/s (5e-12 m...

  15. A Wideband 77GHz, 17.5dBm Power Amplifier in Silicon Abbas Komijani and Ali Hajimiri

    E-Print Network [OSTI]

    Hajimiri, Ali

    such as short-range communication (e.g., 60GHz band) and automotive radar (e.g., 77GHz band) [1 integrated 77GHz power amplifier in silicon. II. FREQUENCY BAND In a collision-avoidance automotive radar copper layers and a thick 4µm aluminum layer as top metal for low-loss interconnects. The breakdown

  16. Solid-State Dynamic Nuclear Polarization at 263 GHz: Spectrometer Design and Experimental Results

    E-Print Network [OSTI]

    Rosay, Melanie

    Dynamic Nuclear Polarization (DNP) experiments transfer polarization from electron spins to nuclear spins with microwave irradiation of the electron spins for enhanced sensitivity in nuclear magnetic resonance (NMR) ...

  17. Neural networks and separation of Cosmic Microwave Background and astrophysical signals in sky maps

    E-Print Network [OSTI]

    C. Baccigalupi; L. Bedini; C. Burigana; G. De Zotti; A. Farusi; D. Maino; M. Maris; F. Perrotta; E. Salerno; L. Toffolatti; A. Tonazzini

    2000-06-21T23:59:59.000Z

    The Independent Component Analysis (ICA) algorithm is implemented as a neural network for separating signals of different origin in astrophysical sky maps. Due to its self-organizing capability, it works without prior assumptions on the signals, neither on their frequency scaling, nor on the signal maps themselves; instead, it learns directly from the input data how to separate the physical components, making use of their statistical independence. To test the capabilities of this approach, we apply the ICA algorithm on sky patches, taken from simulations and observations, at the microwave frequencies, that are going to be deeply explored in a few years on the whole sky, by the Microwave Anisotropy Probe (MAP) and by the {\\sc Planck} Surveyor Satellite. The maps are at the frequencies of the Low Frequency Instrument (LFI) aboard the {\\sc Planck} satellite (30, 44, 70 and 100 GHz), and contain simulated astrophysical radio sources, Cosmic Microwave Background (CMB) radiation, and Galactic diffuse emissions from thermal dust and synchrotron. We show that the ICA algorithm is able to recover each signal, with precision going from 10% for the Galactic components to percent for CMB; radio sources are almost completely recovered down to a flux limit corresponding to $0.7\\sigma_{CMB}$, where $\\sigma_{CMB}$ is the rms level of CMB fluctuations. The signal recovering possesses equal quality on all the scales larger then the pixel size. In addition, we show that the frequency scalings of the input signals can be partially inferred from the ICA outputs, at the percent precision for the dominant components, radio sources and CMB.

  18. Progress toward a MEMS fabricated 100 GHz oscillator.

    SciTech Connect (OSTI)

    Loubriel, Guillermo Manuel; Lemp, Thomas; Weyn, Mark L.; Coleman, Phillip Dale; Rowley, James E. (SAIC, Albuquerque, NM)

    2006-02-01T23:59:59.000Z

    This report summarizes an LDRD effort which looked at the feasibility of building a MEMS (Micro-Electro-Mechanical Systems) fabricated 100 GHz micro vacuum tube. PIC Simulations proved to be a very useful tool in investigating various device designs. Scaling parameters were identified. This in turn allowed predictions of oscillator growth based on beam parameters, cavity geometry, and cavity loading. The electron beam source was identified as a critical element of the design. FEA's (Field Emission Arrays) were purchased to be built into the micro device. Laboratory testing of the FEA's was also performed which pointed out care and handling issues along with maximum current capabilities. Progress was made toward MEMS fabrication of the device. Techniques were developed and successfully employed to build up several of the subassemblies of the device. However, the lower wall fabrication proved to be difficult and a successful build was not completed. Alternative approaches to building this structure have been identified. Although these alternatives look like good solutions for building the device, it was not possible to complete a redesign and build during the timeframe of this effort.

  19. NEAR-FIELD SCANNING MICROWAVE MICROSCOPY: MEASURING LOCAL MICROWAVE PROPERTIES AND ELECTRIC FIELD DISTRIBUTIONS

    E-Print Network [OSTI]

    Anlage, Steven

    WEIF-49 NEAR-FIELD SCANNING MICROWAVE MICROSCOPY: MEASURING LOCAL MICROWAVE PROPERTIES AND ELECTRIC>;ics, University of Maryland, College Park, MD 2OY@-4lll, USA Abstract We describe the near-field scanning methods of scanning probe microscopy have been developed. Generally spea- king one can divide

  20. Relationships between tropical cyclone intensity and satellite based indicators of inner core convection: 85 GHz ice scattering signature and lightning

    E-Print Network [OSTI]

    Cecil, Daniel Joseph

    1997-01-01T23:59:59.000Z

    -1' radius minimum PCT and lightning in Hurricane Felix. . . . . 48 22 Hurricane Luis best track, 12 UTC 27 August - 0 UTC 11 September 1995. . . ?50 23 Luis 85 GHz PCT iield at 0748 V TC 29 August 1995. . . . . . 57 24 Luis OTD lightning observations... at 2348 UTC 28 August 1995. . . . . 25 Luis 85 GHz PCT field at 0905 UTC 30 August 1995. . . . 54 26 Luis 85 GHz PCT field at 2017 UTC 31 August 1995. . . . . . . . 27 Luis 85 GHz PCT field at 0841 UTC 2 September 1995. . . . 28 Luis 85 GHz PCT field...

  1. Implementation of a 1GHZ frontend using transform domain charge sampling techniques

    E-Print Network [OSTI]

    Kulkarni, Mandar Shashikant

    2009-05-15T23:59:59.000Z

    in these architectures due to the built in antialiasing capabilities, jitter robustness at high signal frequencies and flexibility in filter design. This work proposed a 1GHz wideband front end aimed at SDR applications using Transform Domain (TD) sampling techniques...

  2. Commissioning of the superconducting ECR ion source VENUS at 18 GHz

    E-Print Network [OSTI]

    Leitner, Daniela; Abbott, Steven R.; Dwinell, Roger D.; Leitner, Matthaeus; Taylor, Clyde E.; Lyneis, Claude M.

    2004-01-01T23:59:59.000Z

    Commissioning of the Superconducting ECR ion source VENUS atQ Analyzed FC Current (euA) COMMISSIONING RESULTS AT 18 GHZIn 2002 and 2003 initial commissioning at 18 GHz was carried

  3. Calculation of wakefields in a 17 GHz beam-driven photonic band-gap accelerator structure

    E-Print Network [OSTI]

    Hu, Min

    We present the theoretical analysis and computer simulation of the wakefields in a 17 GHz photonic band-gap (PBG) structure for accelerator applications. Using the commercial code CST Particle Studio, the fundamental ...

  4. Direct modulation of semiconductor lasers at f>10 GHz by low-temperature operation

    SciTech Connect (OSTI)

    Lau, K.Y.; Harder, C.; Yariv, A.

    1984-02-01T23:59:59.000Z

    Using a 175-..mu..m-long buried-heterostructure laser fabricated on a semi-insulating substrate operating at -50 /sup 0/C, a direct amplitude modulation bandwidth in excess of 10 GHz has been achieved.

  5. Rare Earth ? N = N* fs fGHZ fp nH fl

    E-Print Network [OSTI]

    Walter, Frederick M.

    Rare Earth ? #12;N to date N = N* fs fGHZ fp nH fl ·N* = 4 x 1011 ·fs = 0.2 ·fGHZ = 0.1 ·fp = 0.8 ·nH = 2 ·fl = 1.0 N = 1.3 x 1010 #12;The Goldilocks Effect Earth is "Just Right" Yes, life on Earth has adapted to Earth, but ... Earth has just the right mass to be ·Tectonically-active ·Retain

  6. Global estimation of precipitation using opaque microwave bands

    E-Print Network [OSTI]

    Chen, Frederick Wey-Min, 1975-

    2004-01-01T23:59:59.000Z

    This thesis describes the use of opaque microwave bands for global estimation of precipitation rate. An algorithm was developed for estimating instantaneous precipitation rate for the Advanced Microwave Sounding Unit (AMSU) ...

  7. Development of a microwave ion and plasma source immersed in a multicusp electron-cyclotron-resonant magnetic field

    SciTech Connect (OSTI)

    Dahimene, M.

    1987-01-01T23:59:59.000Z

    Experimental development and test of an electrodeless microwave (2.45 GHz)-generated plasma and ion source in a discharge pressure range of 6 x 10 /sup -4/-5 x 10/sup -1/ Torr and relatively low power (80-350 W CW) are presented. Also presented is a semi-empirical model applicable to low-pressure microwave discharges with no static magnetic field. Initial experiments studied the properties of variable diffusion length (0.43-1.22 cm) disk-shaped discharges generated and maintained in a cylindrical microwave resonant-cavity applicator for argon and oxygen gases without a static magnetic field. These discharges were characterized by measuring plasma densities and electron temperatures using a Langmuir double probe for different experimental conditions. The measured plasma densities and electron temperatures ranged for 8 x 10/sup 10/ to 5 x 10 /sup 11/ cm/sup -3/ and 2 x 10/sup 4/ to 8 x 10/sup 4/ /sup 0/K, respectively. The ion temperature was less than 500 /sup 0/K. Ion beams were extracted from these discharges using single and double grids. Argon ion-beam currents densities were measured to be 3.0 mA/cm/sup 2/ for the single grid and 5.8 mA/cm/sup 2/ for the double grids with a maximum extraction voltage of 1.7 kV. This applicator was then retrofitted with magnets to study the effect of a multicusp static magnetic field. Using this concept, a new cylindrical microwave applicator was designed and tested.

  8. Integrated microwave and millimeter-wave phased-array designs in silicon technologies

    E-Print Network [OSTI]

    Koh, Kwang-Jin

    2008-01-01T23:59:59.000Z

    for 2-GHz WCDMA direct-conversion transceiver,” IEEE J.for 2-GHz WCDMA direct-conversion transceiver,” IEEE J.

  9. MICROWAVE PROCESSING OF LUNAR SOIL Lawrence A. Taylor1

    E-Print Network [OSTI]

    Taylor, Lawrence A.

    and microwave into hybrid heating can be used to form various structural and mechanical materials for use both

  10. Microwave off-gas treatment apparatus and process

    DOE Patents [OSTI]

    Schulz, Rebecca L. (Aiken, SC); Clark, David E. (Gainesville, FL); Wicks, George G. (North Aiken, SC)

    2003-01-01T23:59:59.000Z

    The invention discloses a microwave off-gas system in which microwave energy is used to treat gaseous waste. A treatment chamber is used to remediate off-gases from an emission source by passing the off-gases through a susceptor matrix, the matrix being exposed to microwave radiation. The microwave radiation and elevated temperatures within the combustion chamber provide for significant reductions in the qualitative and quantitative emissions of the gas waste stream.

  11. Microwave dressing of Rydberg dark states

    E-Print Network [OSTI]

    M. Tanasittikosol; J. D. Pritchard; D. Maxwell; A. Gauguet; K. J. Weatherill; R. M. Potvliege; C. S. Adams

    2011-04-20T23:59:59.000Z

    We study electromagnetically induced transparency (EIT) in the 5s$\\rightarrow$5p$\\rightarrow$46s ladder system of a cold $^{87}$Rb gas. We show that the resonant microwave coupling between the 46s and 45p states leads to an Autler-Townes splitting of the EIT resonance. This splitting can be employed to vary the group index by $\\pm 10^5$ allowing independent control of the propagation of dark state polaritons. We also demonstrate that microwave dressing leads to enhanced interaction effects. In particular, we present evidence for a $1/R^3$ energy shift between Rydberg states resonantly coupled by the microwave field and the ensuing breakdown of the pair-wise interaction approximation.

  12. Experimental investigation of a ``scanner`` microwave amplifier

    SciTech Connect (OSTI)

    Velazco, J.E.; Ceperley, P.H.; Black, W.M.; Thomason, K. [George Mason Univ., Fairfax, VA (United States); Godlove, T.F.; Mako, F.M. [FM Technology, Inc., Fairfax, VA (United States)

    1994-12-31T23:59:59.000Z

    The authors report on initial experimental results of a high-efficiency L-band proof-of-principle microwave amplifier experiment. The prototype under experimental investigation employs a 120 kV, 20A, 5mm diameter, 4 {mu}sec pencil beam. The pencil beam is made to spiral through the interaction with a rotating mode microwave cavity. Efficient energy extraction from the spiral beam is obtained in an output cavity also supporting a rotating mode. The system is immersed in a uniform magnetic field with its amplitude properly adjusted to permit synchronization between the temporal oscillations of the spiral beam and the fields of the rotating modes. This device should be capable of providing coherent, efficient, multimegawatt microwave radiation for a variety of applications appropriate to its frequency range.

  13. Microwave joining of SiC

    SciTech Connect (OSTI)

    Silberglitt, R.; Ahmad, I.; Tian, Y.L. [FM Technologies, Inc., Fairfax, VA (United States)] [and others

    1997-04-01T23:59:59.000Z

    The purpose of this work is to optimize the properties of SiC-SiC joints made using microwave energy. The current focus is on identification of the most effective joining methods for scale-up to large tube assemblies, including joining using SiC produced in situ from chemical precursors. During FY 1996, a new microwave applicator was designed, fabricated and tested that provides the capability for vacuum baking of the specimens and insulation and for processing under inert environment. This applicator was used to join continuous fiber-reinforced (CFCC) SiC/SiC composites using a polymer precursor to form a SiC interlayer in situ.

  14. Ion beams extraction and measurements of plasma parameters on a multi-frequencies microwaves large bore ECRIS with permanent magnets

    SciTech Connect (OSTI)

    Nozaki, Dai; Kiriyama, Ryutaro; Takenaka, Tomoya; Kurisu, Yosuke; Yano, Keisuke; Sato, Fuminobu; Kato, Yushi; Iida, Toshiyuki [Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka Univ., 2-1 Yamadaoka, Suita-shi, Osaka, 565-0871 (Japan)

    2012-11-06T23:59:59.000Z

    We have developed an all-permanent magnet large bore electron cyclotron resonance ion source (ECRIS) for broad ion beam processing. The cylindrically comb-shaped magnetic field configuration is adopted for efficient plasma production and good magnetic confinement. To compensate for disadvantages of fixed magnetic configuration, a traveling wave tube amplifier (TWTA) is used. In the comb-shaped ECRIS, it is difficult to achieve controlling ion beam profiles in the whole inside the chamber by using even single frequency-controllable TWTA (11-13GHz), because of large bore size with all-magnets. We have tried controlling profiles of plasma parameters and then those of extracted ion beams by launching two largely different frequencies simultaneously, i.e., multi-frequencies microwaves. Here we report ion beam profiles and corresponding plasma parameters under various experimental conditions, dependence of ion beams against extraction voltages, and influence of different electrode positions on the electron density profile.

  15. Optimized ECR plasma apparatus with varied microwave window thickness

    DOE Patents [OSTI]

    Berry, L.A.

    1995-11-14T23:59:59.000Z

    The present invention describes a technique to control the radial profile of microwave power in an ECR plasma discharge. In order to provide for a uniform plasma density to a specimen, uniform energy absorption by the plasma is desired. By controlling the radial profile of the microwave power transmitted through the microwave window of a reactor, the profile of the transmitted energy to the plasma can be controlled in order to have uniform energy absorption by the plasma. An advantage of controlling the profile using the window transmission characteristics is that variations to the radial profile of microwave power can be made without changing the microwave coupler or reactor design. 9 figs.

  16. Optimized ECR plasma apparatus with varied microwave window thickness

    DOE Patents [OSTI]

    Berry, Lee A. (Oak Ridge, TN)

    1995-01-01T23:59:59.000Z

    The present invention describes a technique to control the radial profile of microwave power in an ECR plasma discharge. In order to provide for a uniform plasma density to a specimen, uniform energy absorption by the plasma is desired. By controlling the radial profile of the microwave power transmitted through the microwave window of a reactor, the profile of the transmitted energy to the plasma can be controlled in order to have uniform energy absorption by the plasma. An advantage of controlling the profile using the window transmission characteristics is that variations to the radial profile of microwave power can be made without changing the microwave coupler or reactor design.

  17. IMPROVED CONSTRAINTS ON PRIMORDIAL NON-GAUSSIANITY FOR THE WILKINSON MICROWAVE ANISOTROPY PROBE 5-YEAR DATA

    SciTech Connect (OSTI)

    Curto, A.; Martinez-Gonzalez, E.; Barreiro, R. B., E-mail: curto@ifca.unican.e [IFCA, CSIC-Univ. de Cantabria, Avda. los Castros, s/n, E-39005-Santander (Spain)

    2009-11-20T23:59:59.000Z

    We present constraints on the nonlinear coupling parameter f{sub nl} with the Wilkinson Microwave Anisotropy Probe (WMAP) data. We use an updated method based on the spherical Mexican hat wavelet (SMHW) which provides improved constraints on the f{sub nl} parameter. This paper is a continuation of a previous work by Curto et al., where several third-order statistics based on the SMHW were considered. In this paper, we use all the possible third-order statistics computed from the wavelet coefficient maps evaluated at 12 angular scales. The scales are logarithmically distributed from 6.9 arcmin to 500 arcmin. Our analysis indicates that f{sub nl} is constrained to -18 < f{sub nl} < +80 at 95% confidence level (CL) for the combined V+W WMAP map. This value has been corrected by the presence of undetected point sources, which adds a positive contribution of DELTAf{sub nl} = 6 +- 5. Our result excludes at approx99% CL the best-fitting value f{sub nl} = 87 reported by Yadav and Wandelt. We have also constrained f{sub nl} for the Q, V, and W frequency bands separately, finding compatibility with zero at 95% CL for the Q and V bands but not for the W band. We have performed some further tests to understand the cause of this deviation which indicate that systematics associated with the W radiometers could be responsible for this result. Finally, we have performed a Galactic north-south analysis for f{sub nl}. We have not found any asymmetry, i.e., the best-fitting f{sub nl} for the northern pixels is compatible with the best-fitting f{sub nl} for the southern pixels.

  18. Planar controlled zone microwave plasma system

    DOE Patents [OSTI]

    Ripley, Edward B. (Knoxville, TN); Seals, Roland D. (Oak Ridge, TN); Morrell, Jonathan S. (Knoxvlle, TN)

    2011-10-04T23:59:59.000Z

    An apparatus and method for initiating a process gas plasma. A conductive plate having a plurality of conductive fingers is positioned in a microwave applicator. An arc forms between the conductive fingers to initiate the formation of a plasma. A transport mechanism may convey process materials through the plasma. A spray port may be provided to expel processed materials.

  19. The Polarization of the Cosmic Microwave Background

    E-Print Network [OSTI]

    Matias Zaldarriaga

    2003-05-15T23:59:59.000Z

    We summarize the physical mechanism by which the Cosmic Microwave Background acquires a small degree of polarization. We discuss the imprint left by gravitational waves and the use of polarization as a test of the inflationary paradigm. We discuss some physical processes that affect the CMB polarization after recombination such as gravitational lensing and the reionization of the universe.

  20. Calculation of a coaxial microwave torch

    SciTech Connect (OSTI)

    Gritsinin, S. I.; Kossyi, I. A. [Russian Academy of Sciences, Prokhorov Institute of General Physics (Russian Federation); Kulumbaev, E. B.; Lelevkin, V. M. [Kyrgyz-Russian Slavic University (Kyrgyzstan)

    2006-10-15T23:59:59.000Z

    Parameters of an equilibrium microwave discharge in an atmospheric-pressure argon flow in a coaxial waveguide with a truncated inner electrode are calculated numerically by using a self-consistent two-dimensional MHD model. The results obtained agree satisfactorily with the experimental data.

  1. Farinon microwave end of life cycle

    SciTech Connect (OSTI)

    Poe, R.C.

    1996-06-24T23:59:59.000Z

    This engineering report evaluates alternatives for the replacement of the Farinon microwave radio system. The system is beyond its expected life cycle and has decreasing maintainability. Principal applications supported by the Farinon system are two electrical utility monitor and control systems, the Integrated Transfer Trip System (ITTS), and the Supervisory Control and Data Acquisition (SCADA) system.

  2. PHASE NOISE IN MICROWAVE OSCILLATORS AND AMPLIFIERS

    E-Print Network [OSTI]

    Popovic, Zoya

    presents analysis and measurements of phase noise in oscilla- tors and amplifiers. Low phase noise- multaneous small size, low phase noise, DC power consumption and thermal drift is presented. Design stepsPHASE NOISE IN MICROWAVE OSCILLATORS AND AMPLIFIERS by MILOS JANKOVI´C B.E., University of Arkansas

  3. Environmental assessment: South microwave communication facilities

    SciTech Connect (OSTI)

    Not Available

    1989-06-01T23:59:59.000Z

    Western Area Power Administration (Western) is proposing to construct, operate, and maintain eight microwave repeater stations in southwestern Colorado, southeastern Utah, and northern Arizona, in order to meet the minimum fade criteria established by the Western Systems Coordinating Council (WSCC) for the operation and protection of electric power systems. The proposed microwave facilities would increase the reliability of communication. This environmental assessment (EA) describes the existing environmental conditions and the impacts from construction of the eight microwave communication facilities. The EA was prepared in compliance with the National Environmental Policy Act of 1969, the Council on Environmental Quality Regulations (40 CFR 1500-1508), and the Department of Energy Guidelines (52 FR 47662, December 15, 1987). The proposed project would consist of constructing eight microwave facilities, each of which would include a self-supported lattice tower, an equipment building, a propane tank, distribution lines to provide electric power to the sites, and access roads to the sites. The facilities would be constructed in San Miguel and Montezuma Counties in Colorado, San Juan County, Utah, and Navajo, Apache, Coconino, and Yavapai Counties in Arizona. 20 refs., 2 figs., 2 tabs.

  4. Analysis of characteristic of microwave regeneration for diesel particulate filter

    SciTech Connect (OSTI)

    Ning Zhi; Zhang Guanglong; Lu Yong; Liu Junmin; Gao Xiyan; Liang Iunhui; Chen Jiahua [Dalian Univ. of Technology (China)

    1995-12-31T23:59:59.000Z

    The mathematical model for the microwave regeneration of diesel particulate filter is proposed according to the characteristic of microwave regeneration process. The model is used to calculate the temperature field, distribution of particulate and density field of oxygen in the filter during the process of regeneration with typical ceramic foam particulate filter data. The parametric study demonstrates how some of the main parameters, such as microwave attenuation constant of the filter, filter particulate loading, the power and distribution of microwave energy and so on, affect the efficiency of regeneration, the maximum filter temperature and regeneration duration. The results show that it is possible to regenerate the diesel particulate filters in certain conditions by using microwave energy. This paper can give one a whole understanding to several main factors that have effects on the process of microwave regeneration and provide a theoretical basis for the optimal design of the microwave regeneration system.

  5. Selected applications of microwave radiometric techniques 

    E-Print Network [OSTI]

    Jean, Buford Randall

    1971-01-01T23:59:59.000Z

    of oil (=2) is much less than that of water (=80) [17]. Since the calming effect of an oil layer on a water surface tends to decrease the effective emissivity, the possibility exists for an oil spill to be "invisible" for certain frequencies, viewing... above about 30 GHz can be expected to provide an oil slick detection capability [34]. The higher fre- quencies are required because an uncontained oil spill spreads rapidly, and it is estimated that an oil pollution surveillance technique should...

  6. The Linear Polarization of Sagittarius A* II. VLA and BIMA Polarimetry at 22, 43 and 86 GHz

    E-Print Network [OSTI]

    Geoffrey C. Bower; Melvyn C. H. Wright; Donald C. Backer; Heino Falcke

    1999-07-21T23:59:59.000Z

    We present a search for linear polarization at 22 GHz, 43 GHz and 86 GHz from the nearest super massive black hole candidate, Sagittarius A*. We find upper limits to the linear polarization of 0.2%, 0.4% and 1%, respectively. These results strongly support the conclusion of our centimeter wavelength spectro-polarimetry that Sgr A* is not depolarized by the interstellar medium but is in fact intrinsically depolarized.

  7. A low phase noise microwave frequency synthesis for a high-performance cesium vapor cell atomic clock

    SciTech Connect (OSTI)

    François, B.; Boudot, R. [FEMTO-ST, CNRS, Université de Franche-Comté, 26 chemin de l'Epitaphe, 25030 Besançon (France); Calosso, C. E. [INRIM, Strada delle Cacce 91, 10135 Torino (Italy); Danet, J. M. [LNE-SYRTE, Observatoire de Paris, CNRS-UPMC, 61 avenue de l'Observatoire, 75014 Paris (France)

    2014-09-15T23:59:59.000Z

    We report the development, absolute phase noise, and residual phase noise characterization of a 9.192?GHz microwave frequency synthesis chain devoted to be used as a local oscillator in a high-performance cesium vapor cell atomic clock based on coherent population trapping (CPT). It is based on frequency multiplication of an ultra-low phase noise 100 MHz oven-controlled quartz crystal oscillator using a nonlinear transmission line-based chain. Absolute phase noise performances of the 9.192?GHz output signal are measured to be ?42, ?100, ?117 dB?rad{sup 2}/Hz and ?129 dB?rad{sup 2}/Hz at 1 Hz, 100 Hz, 1 kHz, and 10 kHz offset frequencies, respectively. Compared to current results obtained in a state-of-the-art CPT-based frequency standard developed at LNE-SYRTE, this represents an improvement of 8 dB and 10 dB at f = 166 Hz and f = 10 kHz, respectively. With such performances, the expected Dick effect contribution to the atomic clock short term frequency stability is reported at a level of 6.2 × 10{sup ?14} at 1 s integration time, that is a factor 3 higher than the atomic clock shot noise limit. Main limitations are pointed out.

  8. 12.2-GHz methanol maser MMB follow-up catalogue - III. Longitude range 10 to 20 degrees

    E-Print Network [OSTI]

    Breen, Shari; Caswell, James; Green, James; Voronkov, Maxim; Avison, Adam; Fuller, Gary; Quinn, Lyshia; Titmarsh, Anita

    2013-01-01T23:59:59.000Z

    We present the third instalment of a series of catalogues presenting 12.2-GHz methanol maser observations made towards each of the 6.7-GHz methanol masers detected in the Methanol Multibeam (MMB) Survey. The current portion of the catalogue includes the Galactic longitude region 10 to 20 degrees, where we detect 47 12.2-GHz methanol masers towards 99 6.7-GHz targets. We compare the occurrence of 12.2-GHz methanol masers with water maser emission, for which all 6.7-GHz methanol masers in the 6 to 20 degrees longitude range have now been searched. We suggest that the water masers follow a more complicated evolutionary scenario than has been found for the methanol and OH masers, likely due to their different pumping mechanisms. Comparisons of the 6.7-GHz methanol to OH maser peak flux density ratio and the luminosity of the associated 12.2-GHz sources suggests that the 12.2-GHz maser luminosity begins to decline around the time that an OH maser becomes detectable.

  9. Path delay model based on -stable distribution for the 60GHz indoor channel.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    monolithic microwave integrated circuit (MMIC) transmitters and receivers will make possible the use of hand present the statistical results of fitting the delays to -stable distributions. In the third section

  10. Fabrication of an optically driven 10 GHz ring resonator on a gallium arsenide substrate

    E-Print Network [OSTI]

    McGregor, Douglas Scott

    1989-01-01T23:59:59.000Z

    /D converters, optical detectors, dc to rf converters, and millimeter-wave or microwave generators. Photoconductors can be easily integrated with microelectronic devices as well as microwave circuits. Recently, an optically excited photoconductive switch... is the barrier height and y, is the electron affinity for the semiconductor. Current flow at a metal-semiconductor barrier is due mainly to majority carriers. The four major current transport methods are thermionic emission over the barrier, quantum...

  11. Theoretical and experimental study of 2.45 GHz rectifying antennas 

    E-Print Network [OSTI]

    McSpadden, James Oliver

    1993-01-01T23:59:59.000Z

    Depending on the type of application, different variables must be considered. A potential application for beamed power is shown in Figure 2. A ground station transmits microwave power to a high altitude airship. The airship can be used as a communications... platform. Though onboard solar cells could supply station operating demands during the daylight hours, microwave power could supply this demand at night. Thus, a rotating airship would require the rectenna to be circular or dual polarized. The weight...

  12. Digital-photonic synthesis of ultra-low noise tunable signals from RF to 100 GHz

    E-Print Network [OSTI]

    Fortier, T M; Quinlan, F; Baynes, F N; Metcalf, A J; Hati, A; Ludlow, A; Hinkley, N; Shimizu, M; Ishibashi, T; Campbell, J C; Diddams, S A

    2015-01-01T23:59:59.000Z

    The demand for higher data rates and better synchronization in communication and navigation systems necessitates the development of new wideband and tunable sources with noise performance exceeding that provided by traditional oscillators and synthesizers. Precision synthesis is paramount for providing frequency references and timing in a broad range of applications including next-generation telecommunications, high precision measurement, and radar and sensing. Here we describe a digital-photonic synthesizer (DPS) based on optical frequency division that enables the generation of widely tunable signals from near DC to 100 GHz with a fractional frequency instability of 1 part in 10^15. The spectral purity of the DPS derived signals represents an improvement in close-to-carrier noise performance over the current state-of-the-art of nearly 7 orders of magnitude in the W-band (100 GHz), and up to 5 orders of magnitude in the X-band (10 GHz).

  13. DISCOVERY OF 6.035 GHz HYDROXYL MASER FLARES IN IRAS 18566+0408

    SciTech Connect (OSTI)

    Al-Marzouk, A. A.; Araya, E. D. [Physics Department, Western Illinois University, 1 University Circle, Macomb, IL 61455 (United States); Hofner, P. [Physics Department, New Mexico Institute of Mining and Technology, 801 Leroy Place, Socorro, NM 87801 (United States); Kurtz, S. [Centro de Radioastronomia y Astrofisica, Universidad Nacional Autonoma de Mexico, Apdo. Postal 3-72, 58090, Morelia, Michoacan (Mexico); Linz, H. [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany); Olmi, L. [INAF, Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125 Firenze (Italy)

    2012-05-10T23:59:59.000Z

    We report the discovery of 6.035 GHz hydroxyl (OH) maser flares toward the massive star-forming region IRAS 18566+0408 (G37.55+0.20), which is the only region known to show periodic formaldehyde (4.8 GHz H{sub 2}CO) and methanol (6.7 GHz CH{sub 3}OH) maser flares. The observations were conducted between 2008 October and 2010 January with the 305 m Arecibo Telescope in Puerto Rico. We detected two flare events, one in 2009 March and one in 2009 September to November. The OH maser flares are not simultaneous with the H{sub 2}CO flares, but may be correlated with CH{sub 3}OH flares from a component at corresponding velocities. A possible correlated variability of OH and CH{sub 3}OH masers in IRAS 18566+0408 is consistent with a common excitation mechanism (IR pumping) as predicted by theory.

  14. Apparatus and method for microwave processing of materials

    DOE Patents [OSTI]

    Johnson, Arvid C. (Lake in the Hills, IL); Lauf, Robert J. (Oak Ridge, TN); Bible, Don W. (Clinton, TN); Markunas, Robert J. (Chapel Hill, NC)

    1996-01-01T23:59:59.000Z

    A variable frequency microwave heating apparatus (10) designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity (34) for testing or other selected applications. The variable frequency heating apparatus (10) is used in the method of the present invention to monitor the resonant processing frequency within the furnace cavity (34) depending upon the material, including the state thereof, from which the workpiece (36) is fabricated. The variable frequency microwave heating apparatus (10) includes a microwave signal generator (12) and a high-power microwave amplifier (20) or a microwave voltage-controlled oscillator (14). A power supply (22) is provided for operation of the high-power microwave oscillator (14) or microwave amplifier (20). A directional coupler (24) is provided for detecting the direction and amplitude of signals incident upon and reflected from the microwave cavity (34). A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

  15. Apparatus and method for microwave processing of materials

    DOE Patents [OSTI]

    Johnson, A.C.; Lauf, R.J.; Bible, D.W.; Markunas, R.J.

    1996-05-28T23:59:59.000Z

    Disclosed is a variable frequency microwave heating apparatus designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity for testing or other selected applications. The variable frequency heating apparatus is used in the method of the present invention to monitor the resonant processing frequency within the furnace cavity depending upon the material, including the state thereof, from which the workpiece is fabricated. The variable frequency microwave heating apparatus includes a microwave signal generator and a high-power microwave amplifier or a microwave voltage-controlled oscillator. A power supply is provided for operation of the high-power microwave oscillator or microwave amplifier. A directional coupler is provided for detecting the direction and amplitude of signals incident upon and reflected from the microwave cavity. A first power meter is provided for measuring the power delivered to the microwave furnace. A second power meter detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load. 10 figs.

  16. VLBI detections of a source weaker than 100 mJy at 86 GHz

    E-Print Network [OSTI]

    E. Middelberg; A. L. Roy; R. C. Walker; H. Falcke

    2004-09-27T23:59:59.000Z

    We use a new phase-calibration strategy to calibrate the phase of 86 GHz VLBI observations of the FR I radio galaxy NGC 4261. Instead of switching between a calibrator source and the target source, the target was observed while rapidly switching between the target frequency and a lower reference frequency. Self-calibration at the reference frequency yielded phase corrections which were multiplied with the frequency ratio and applied to the target frequency visibilities. The resulting detection of NGC 4261 is, to our knowledge, the first of NGC 4261 with 86 GHz VLBI, and it is also the weakest source so far detected with VLBI at that frequency.

  17. Performance of 3.9 GHz SRF cavities at Fermilab's ILCTA_MDB nhorizontal test stand

    SciTech Connect (OSTI)

    Harms, Elvin; Hocker, Andy; /Fermilab

    2008-08-01T23:59:59.000Z

    Fermilab is building a cryomodule containing four 3.9 GHz superconducting radio frequency (SRF) cavities for the Free electron LASer in Hamburg (FLASH) facility at the Deutsches Elektronen-SYnchrotron (DESY) laboratory. Before assembling the cavities into the cryomodule, each individual cavity is tested at Fermilab's Horizontal Test Stand (HTS). The HTS provides the capability to test fully-dressed SRF cavities at 1.8 K with high-power pulsed RF in order to verify that the cavities achieve performance requirements under these conditions. The performance at the HTS of the 3.9 GHz cavities built for FLASH is presented here.

  18. 2002 AUGUST 24 LIMB FLARE LOOP: DYNAMICS OF MICROWAVE BRIGHTNESS DISTRIBUTION

    SciTech Connect (OSTI)

    Reznikova, V. E.; Ji, H. [Purple Mountain Observatory, Chinese Academy of Sciences, 2 West Beijing Road, Nanjing 210008 (China); Melnikov, V. F.; Gorbikov, S. P.; Pyatakov, N. P. [Radiophysical Research Institute (NIRFI), Nizhny Novgorod 603950 (Russian Federation); Shibasaki, K. [Nobeyama Solar Radio Observatory/NAOJ, Nagano 384-1305 (Japan); Myagkova, I. N. [Lomonosov Moscow State University, Skobeltsyn Institute of Nuclear Physics, Moscow (Russian Federation)], E-mail: vreznikova@nirfi.sci-nnov.ru

    2009-05-20T23:59:59.000Z

    High-resolution radio observation of Nobeyama Radioheliograph at 17 and 34 GHz allowed studying the dynamics of microwave brightness distribution along the giant limb flaring loop in the event of 2002 August 24. It is found that on the rising phase of the radio burst the brightness distribution was highly asymmetric, with a strong maximum near the southern footpoint (SFP) and much weaker brightness enhancements near the loop top (LT) and northern footpoint. On the decay phase, the LT gradually became most bright. The similar dynamics of brightness distribution are shown to happen for all major temporal subpeaks of the burst. Results of our diagnostics show two important properties: (1) the number density of mildly relativistic electrons in the LT is much higher than near the footpoints (FPs) during rise, maximum and decay of each major peak; and (2) the ratio of the electron number densities in the LT and an FP increases from the maximum to decay phase. Model simulations with making use of the nonstationary Fokker-Planck equation have allowed us to find the model explaining the major properties of the microwave brightness distribution and dynamics. The model is characterized by a compact source of electrons located near the center of an asymmetric magnetic loop; the source is nonstationary, long lasting, and injecting high-energy electrons with the pitch-angle distribution mostly directed toward the SFP but also having a very weak isotropic component. This easily explains the observed brightness asymmetry. The observed dynamics comes due to two reasons: faster precipitation of electrons having their mirror points near the ends of the magnetic trap, and relatively faster decay of the lower energy electrons responsible for the gyrosynchrotron emission near the FPs with higher magnetic field.

  19. Improved foilless Ku-band transit-time oscillator for generating gigawatt level microwave with low guiding magnetic field

    SciTech Connect (OSTI)

    Ling, Junpu; He, Juntao, E-mail: hejuntao12@163.com; Zhang, Jiande; Jiang, Tao; Hu, Yi [College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

    2014-09-15T23:59:59.000Z

    An improved foilless Ku-band transit-time oscillator with low guiding magnetic field is proposed and investigated in this paper. With a non-uniform buncher and a coaxial TM{sub 02} mode dual-resonant reflector, this improved device can output gigawatt level Ku-band microwave with relatively compact radial dimensions. Besides the above virtue, this novel reflector also has the merits of high TEM reflectance, being more suitable for pre-modulating the electron beam and enhancing the conversion efficiency. Moreover, in order to further increase the conversion efficiency and lower the power saturation time, a depth-tunable coaxial collector and a resonant cavity located before the extractor are employed in our device. Main structure parameters of the device are optimized by particle in cell simulations. The typical simulation result is that, with a 380?kV, 8.2?kA beam guided by a magnetic field of about 0.6?T, 1.15?GW microwave pulse at 14.25?GHz is generated, yielding a conversion efficiency of about 37%.

  20. Sideband characterization and atmospheric observations with various 340 GHz heterodyne receivers

    SciTech Connect (OSTI)

    Renker, Matthias, E-mail: renker@iap.unibe.ch; Murk, Axel [Institute of Applied Physics, University of Bern, Bern (Switzerland); Rea, Simon P. [STFC Rutherford Appleton Laboratory, Didcot, Oxfordshire (United Kingdom); Emrich, A.; Frisk, U. [OMNISYS Instruments, Västra Frölunda (Sweden)

    2014-08-15T23:59:59.000Z

    This paper describes sideband response measurements and atmospheric observations with a double sideband and two Single Sideband (SSB) receiver prototypes developed for the multi-beam limb sounder instrument stratosphere-troposphere exchange and climate monitor radiometer. We first show an advanced Fourier-Transform Spectroscopy (FTS) method for sideband response and spurious signal characterization. We then present sideband response measurements of the different prototype receivers and we compare the results of the SSB receivers with sideband measurements by injecting a continuous wave signal into the upper and lower sidebands. The receivers were integrated into a total-power radiometer and atmospheric observations were carried out. The observed spectra were compared to forward model spectra to conclude on the sideband characteristics of the different receivers. The two sideband characterization methods show a high degree of agreement for both SSB receivers with various local oscillator settings. The measured sideband response was used to correct the forward model simulations. This improves the agreement with the atmospheric observations and explains spectral features caused by an unbalanced sideband response. The FTS method also allows to quantify the influence of spurious harmonic responses of the receiver.

  1. A container for heat treating materials in microwave ovens

    DOE Patents [OSTI]

    Holcombe, C.E.; Dykes, N.L.; Kimrey, H.D. Jr.; Mills, J.E.

    1988-01-26T23:59:59.000Z

    The efficiency of a microwave oven of a conventional two-source configuration and energy level is increased by providing the oven with a container for housing a refractory material to be treated. The container is formed to top and bottom walls transparent to microwaves while the sidewalls, in a circular configuration, are formed of a nonmetallic material opaque to microwave radiation for reflecting the radiation penetrating the top and bottom walls radially inwardly into the center of the container wherein a casket of heat-insulating material is provided for housing the material to be heat treated. The reflection of the microwave radiation from the sidewalls increases the concentration of the microwaves upon the material being heat treated while the concentration of the microwaves upon the material being heat treated while the casket retains the heat to permit the heating of the material to a substantially higher temperature than achievable in the oven without the container.

  2. Quantum and Wave Dynamical Chaos in Superconducting Microwave Billiards

    E-Print Network [OSTI]

    B. Dietz; A. Richter

    2015-04-16T23:59:59.000Z

    Experiments with superconducting microwave cavities have been performed in our laboratory for more than two decades. The purpose of the present article is to recapitulate some of the highlights achieved. We briefly review (i) results obtained with flat, cylindrical microwave resonators, so-called microwave billiards, concerning the universal fluctuation properties of the eigenvalues of classically chaotic systems with no, a threefold and a broken symmetry; (ii) summarize our findings concerning the wave-dynamical chaos in three-dimensional microwave cavities; (iii) present a new approach for the understanding of the phenomenon of dynamical tunneling which was developed on the basis of experiments that were performed recently with unprecedented precision, and finally, (iv) give an insight into an ongoing project, where we investigate universal properties of (artificial) graphene with superconducting microwave photonic crystals that are enclosed in a microwave resonator, i.e., so-called Dirac billiards.

  3. Quantum and Wave Dynamical Chaos in Superconducting Microwave Billiards

    E-Print Network [OSTI]

    B. Dietz; A. Richter

    2015-04-17T23:59:59.000Z

    Experiments with superconducting microwave cavities have been performed in our laboratory for more than two decades. The purpose of the present article is to recapitulate some of the highlights achieved. We briefly review (i) results obtained with flat, cylindrical microwave resonators, so-called microwave billiards, concerning the universal fluctuation properties of the eigenvalues of classically chaotic systems with no, a threefold and a broken symmetry; (ii) summarize our findings concerning the wave-dynamical chaos in three-dimensional microwave cavities; (iii) present a new approach for the understanding of the phenomenon of dynamical tunneling which was developed on the basis of experiments that were performed recently with unprecedented precision, and finally, (iv) give an insight into an ongoing project, where we investigate universal properties of (artificial) graphene with superconducting microwave photonic crystals that are enclosed in a microwave resonator, i.e., so-called Dirac billiards.

  4. Analysis of cloud layer structure in Shouxian, China using RS92 radiosonde aided by 95 GHz cloud radar

    E-Print Network [OSTI]

    Li, Zhanqing

    Analysis of cloud layer structure in Shouxian, China using RS92 radiosonde aided by 95 GHz cloud to analyze cloud vertical structure over this area by taking advantage of the first direct measurements of cloud vertical layers from the 95 GHz radar. Singlelayer, twolayer, and threelayer clouds account for 28

  5. On the design of a 55 GHz Si/SiGe HBT frequency doubler operating close to f max

    E-Print Network [OSTI]

    On the design of a 55 GHz Si/SiGe HBT frequency doubler operating close to f max S. Bruce, M. Kim. Abstract In this paper we present for the first time experimental results on a frequency doubler using a Si/SiGe GHz, for the Si/SiGe HBT, the conversion efficiency in a not completely optimised circuit was found

  6. Cavity Microwave Searches for Cosmological Axions

    SciTech Connect (OSTI)

    Carosi, G; van Bibber, K

    2007-01-22T23:59:59.000Z

    This chapter will cover the search for dark matter axions based on microwave cavity experiments proposed by Pierre Sikivie. We will start with a brief overview of halo dark matter and the axion as a candidate. The principle of resonant conversion of axions in an external magnetic field will be described as well as practical considerations in optimizing the experiment as a signal-to-noise problem. A major focus of this chapter will be the two complementary strategies for ultra-low noise detection of the microwave photons--the 'photon-as-wave' approach (i.e. conventional heterojunction amplifiers and soon to be quantum-limited SQUID devices), and 'photon-as-particle' (i.e. Rydberg-atom single-quantum detection). Experimental results will be presented; these experiments have already reached well into the range of sensitivity to exclude plausible axion models, for limited ranges of mass. The section will conclude with a discussion of future plans and challenges for the microwave cavity experiment.

  7. Joining of thermoplastic substrates by microwaves

    DOE Patents [OSTI]

    Paulauskas, Felix L. (Oak Ridge, TN); Meek, Thomas T. (Knoxville, TN)

    1997-01-01T23:59:59.000Z

    A method for joining two or more items having surfaces of thermoplastic material includes the steps of depositing an electrically-conductive material upon the thermoplastic surface of at least one of the items, and then placing the other of the two items adjacent the one item so that the deposited material is in intimate contact with the surfaces of both the one and the other items. The deposited material and the thermoplastic surfaces contacted thereby are then exposed to microwave radiation so that the thermoplastic surfaces in contact with the deposited material melt, and then pressure is applied to the two items so that the melted thermoplastic surfaces fuse to one another. Upon discontinuance of the exposure to the microwave energy, and after permitting the thermoplastic surfaces to cool from the melted condition, the two items are joined together by the fused thermoplastic surfaces. The deposited material has a thickness which is preferably no greater than a skin depth, .delta..sub.s, which is related to the frequency of the microwave radiation and characteristics of the deposited material in accordance with an equation.

  8. Issues in microwave power systems engineering

    SciTech Connect (OSTI)

    Dickinson, R.M. [California Inst. of Tech., Pasadena, CA (United States). Jet Propulsion Lab.

    1996-12-31T23:59:59.000Z

    The key issues in microwave power system engineering are beam safety, frequency allocation, and affordability. These major issues are presented, discussed, and suggestions for resolving them are offered. The issue of beam safety can be captured in the phrase ``Fear of Frying.`` Can a properly engineered beamed power safety system allay the public perception of microwave radiation dangers? Openness, visibility, and education may be keys to resolving this issue satisfactorily. ``Not in my Spectrum`` is a phrase that is frequently encountered in connection with the issue of where can the microwave power beam frequency be located. International cooperation may provide a part of the solution to this issue. ``Wow, that much?`` is a phrase encountered when dealing with the issue of economic affordability of large beamed power systems. A phased engineering approach for multiple uses even during construction is presented to aid in garnering revenue during the system build phase. Also, dual mode dc-RF converters are encouraged for bi-directional power flow utility and economies of scale in production.

  9. Demonstration of a 140-GHz 1-kW Confocal Gyro-Traveling-Wave Amplifier

    E-Print Network [OSTI]

    Temkin, Richard J.

    The theory, design, and experimental results of a wideband 140-GHz 1-kW pulsed gyro-traveling-wave amplifier (gyro-TWA) are presented. The gyro-TWA operates in the HE [subscript 06] mode of an overmoded quasi-optical ...

  10. MISO time reversal and delay spread compression for FWA channels at 5GHz

    E-Print Network [OSTI]

    Papanicolaou, George C.

    MISO time reversal and delay spread compression for FWA channels at 5GHz Persefoni Kyritsi, Member (MISO) can reduce the delay spread of the channel impulse response by a factor of 2-3, depending transmitter instead. The paper is structured as follows. Section II describes the concept of TR in a MISO

  11. Elastic properties of transparent nano-polycrystalline diamond measured by GHz-ultrasonic interferometry and resonant

    E-Print Network [OSTI]

    Jacobsen, Steven D.

    Elastic properties of transparent nano-polycrystalline diamond measured by GHz-ultrasonic interferometry Sphere resonance Nano-polycrystalline diamond NPD Elastic properties Superhard materials a b s t r a c t The sound velocities and elastic moduli of transparent nano-polycrystalline diamond (NPD) have

  12. EXPERIMENTAL DEMONSTRATION OF WAKEFIELD EFFECTS IN A 250 GHZ PLANAR DIAMOND ACCELERATING STRUCTURE*

    E-Print Network [OSTI]

    Brookhaven National Laboratory

    of a rectangular waveguide loaded with polycrystalline CVD diamond plates as an accelerating structure. It should polycrystalline diamond plates loaded in a 6 cm long waveguide (Fig. 2). The beam gap was 200 microns (Fig. TM11EXPERIMENTAL DEMONSTRATION OF WAKEFIELD EFFECTS IN A 250 GHZ PLANAR DIAMOND ACCELERATING STRUCTURE

  13. 1. ABSTRACT A 1.4-GHz LC voltage-controlled oscillator has

    E-Print Network [OSTI]

    Lee, Thomas H.

    1. ABSTRACT A 1.4-GHz LC voltage-controlled oscillator has been implemented in a MOSIS 0.5-µm CMOS integrated, low noise, low power voltage-controlled oscillator (VCO). For higher quality receivers, an LC the overall phase noise. In this paper, we present such an LC voltage-controlled oscillator fabricated through

  14. A 24-GHZ ACTIVE PATCH ARRAY Dai Lu, Milan Kovacevic, Jon Hacker and David Rutledge

    E-Print Network [OSTI]

    proved a 12-dB antenna gain. A power amplifier and a low noise amplifier are designed on a single Ga noise amplifier applications, more recently GaAs PHEMTs have found applications in the low to medium amplifier and low noise amplifier are designed at 24 GHz. While the T/R switch loss is greatly reduced

  15. 1.3 GHz Cavity Weld to Helium Vessel A. Schmidt, A. Matheisen

    E-Print Network [OSTI]

    room conditions which are classified as ASTM class 10 (ISO 4) quality. All processes for He tank of completion of helium tank and module assembly techniques as well. An overview on the sequences and processes for tank installation for the DESY 1.3 GHz resonators will be given. Introduction Improvements

  16. RF PULSED TESTS ON 3GHZ NIOBIUM CAVITIES J. Le Duff, C. Thomas

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    RF PULSED TESTS ON 3GHZ NIOBIUM CAVITIES J. Le Duff, C. Thomas , G. Bienvenu, H.Sun LAL, Orsay limits have been pushed back thanks to improvements of niobium purity, cavity preparation, as- sembling mT or 50MV/m accelerating field Eacc for TESLA shape bulk niobium (Nb) cavities at T = 0 K

  17. Planning of Low-Cost 77-GHz Radar Transceivers for Automotive Applications

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    . Moghavvemi University ofMalaya INTRODUCTION The use of electronics in the automotive industry will reach (or the position and speed as with other components used in the automotive industry, radars will find widespreadPlanning of Low-Cost 77-GHz Radar Transceivers for Automotive Applications H. Ameri, A. Attaran & M

  18. A 100 MHz 2.5 GHz Direct Conversion CMOS Transceiver for SDR Applications

    E-Print Network [OSTI]

    Ellingson, Steven W.

    A 100 MHz ­ 2.5 GHz Direct Conversion CMOS Transceiver for SDR Applications Gio Cafaro, Tom frequency switching and phase noise of ­123 dBc/Hz at 25 KHz offset. Index Terms -- CMOS, Direct Conversion are not practical in today's technology [5]-[7]. Direct conversion is preferred for this reason, but it has some

  19. Superconducting quantum interference device as a near-quantum-limited amplifier at 0.5 GHz

    E-Print Network [OSTI]

    Le Roy, Robert J.

    Superconducting quantum interference device as a near-quantum-limited amplifier at 0.5 GHz Michael 94720 Received 10 October 2000; accepted for publication 14 December 2000 A dc superconducting quantum, for example, superconducting transition-edge sensors for infrared, optical, and ultraviolet wavelengths,2

  20. Microwave-Assisted Ignition for Improved Internal Combustion Engine Efficiency

    E-Print Network [OSTI]

    DeFilippo, Anthony Cesar

    2013-01-01T23:59:59.000Z

    OH. ” Proceedings of the Combustion Institute: 32(2):3171-Thermochemical Database for Combustion. ” Argonne NationalMicrowave Radiation. ” Combustion Science and Technology:

  1. A Calibration of a Microwave Telescope Christopher Herzog

    E-Print Network [OSTI]

    A Calibration of a Microwave Telescope Christopher Herzog February 27, 2004 1 Calculating the Polarization Change This calibration experiment relies on an ability to calculate what happens

  2. aces microwave link: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Lan 2010-01-01 152 Engineering Research and Development Microwave Imaging Technology Plasma Physics and Fusion Websites Summary: Engineering Research and Development MVG Paris...

  3. Microwave-Assisted Ignition for Improved Internal Combustion Engine Efficiency

    E-Print Network [OSTI]

    DeFilippo, Anthony Cesar

    2013-01-01T23:59:59.000Z

    J. B. (1988) Internal Combustion Engine Fundamentals.novel microwave internal combustion engine ignition source,in the Internal Combustion Engine." SAE Technical Paper

  4. advanced microwave sounding: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Aires, Filipe 35 IEEE MICROWAVE AND GUIDED WAVE LETTERS, VOL. 9, NO. 9, SEPTEMBER 1999 345 DC and RF Characteristics of Advanced MIM Engineering Websites Summary: of Advanced...

  5. Method and apparatus for thickness measurement using microwaves

    DOE Patents [OSTI]

    Woskov, Paul (Bedford, MA) [Bedford, MA; Lamar, David A. (West Richland, WA) [West Richland, WA

    2001-01-01T23:59:59.000Z

    The method for measuring the thickness of a material which transmits a detectable amount of microwave radiation includes irradiating the material with coherent microwave radiation tuned over a frequency range. Reflected microwave radiation is detected, the reflected radiation having maxima and minima over the frequency range as a result of coherent interference of microwaves reflected from reflecting surfaces of the material. The thickness of the material is determined from the period of the maxima and minima along with knowledge of the index of refraction of the material.

  6. Hydrogen recovery from extraterrestrial materials using microwave energy

    SciTech Connect (OSTI)

    Tucker, D.S.; Vaniman, D.T.; Anderson, J.L.; Clinard, F.W. Jr.; Feber, R.C. Jr.; Frost, H.M.; Meek, T.T.; Wallace, T.C.

    1984-01-01T23:59:59.000Z

    The feasibility of recovering hydrogen from extraterrestrial materials (lunar and Martian soils, asteroids) using microwave energy is presented. Reasons for harvesting and origins and locations of hydrogen are reviewed. Problems of hydrogen recovery are discussed in terms of hydrogen release characteristics and microwave coupling to insulating materials. From results of studies of hydrogen diffusivities (oxides, glasses) and tritium release (oxides) as well as studies of microwave coupling to ilmenite, alkali basalt and ceramic oxides it is concluded that using microwave energy in hydrogen recovery from extraterrestrial materials could be the basis for a workable process.

  7. advanced microwave circuits: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    transition of photons in circuit quantum electrodynamics electrodynamics QED , superconduct- ing qubits are coupled with microwave photons in a trans- mission line and a...

  8. Microwave vs. Electric Kettle: Which Appliance Is in Hot Water...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    is more efficient? Tell Us Addthis Microwave or electric kettle, which appliance should win the honor of heating your water? | Graphic by Stacy Buchanan, National Renewable Energy...

  9. Gas breakdown driven by L band short-pulse high-power microwave

    SciTech Connect (OSTI)

    Yang Yiming; Yuan Chengwei; Qian Baoliang [College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

    2012-12-15T23:59:59.000Z

    High power microwave (HPM) driven gas breakdown is a major factor in limiting the radiation and transmission of HPM. A method that HPM driven gas breakdown could be obtained by changing the aperture of horn antenna is studied in this paper. Changing the effective aperture of horn antenna can adjust the electric field in near field zone, leading to gas breakdown. With this method, measurements of air and SF{sub 6} breakdowns are carried out on a magnetically insulated transmission-line oscillators, which is capable of generating HPM with pulse duration of 30 ns, and frequency of 1.74 GHz. The typical breakdown waveforms of air and SF{sub 6} are presented. Besides, the breakdown field strengths of the two gases are derived at different pressures. It is found that the effects of air and SF{sub 6} breakdown on the transmission of HPM are different: air breakdown mainly shortens the pulse width of HPM while SF{sub 6} breakdown mainly reduces the peak output power of HPM. The electric field threshold of SF{sub 6} is about 2.4 times larger than that of air. These differences suggest that gas properties have a great effect on the transmission characteristic of HPM in gases.

  10. Optimizing a microwave gas ion source for continuous-flow accelerator mass spectrometry

    SciTech Connect (OSTI)

    Reden, K. F. von; Roberts, M. L.; Burton, J. R.; Beaupre, S. R. [Geology and Geophysics Department, Woods Hole Oceanographic Institution (WHOI), Woods Hole, Massachusetts 02543 (United States)

    2012-02-15T23:59:59.000Z

    A 2.45 GHz microwave ion source coupled with a magnesium charge exchange canal (C x C) has been successfully adapted to a large acceptance radiocarbon accelerator mass spectrometry system at the National Ocean Sciences Accelerator Mass Spectrometry (AMS) Facility, Woods Hole Oceanographic Institution. CO{sub 2} samples from various preparation sources are injected into the source through a glass capillary at 370 {mu}l/min. Routine system parameters are about 120-140 {mu}A of negative {sup 12}C current after the C x C, leading to about 400 {sup 14}C counts per second for a modern sample and implying a system efficiency of 0.2%. While these parameters already allow us to perform high-quality AMS analyses on large samples, we are working on ways to improve the output of the ion source regarding emittance and efficiency. Modeling calculations suggest modifications in the extraction triode geometry, shape, and size of the plasma chamber could improve emittance and, hence, ion transport efficiency. Results of experimental tests of these modifications are presented.

  11. Low temperature charge transport and microwave absorption of carbon coated iron nanoparticles–polymer composite films

    SciTech Connect (OSTI)

    Prasad, V., E-mail: vishnu@physics.iisc.ernet.in [Department of Physics, Indian Institute of Science, Bangalore 560 012 (India)

    2012-06-15T23:59:59.000Z

    Highlights: ? Carbon coated Fe nanoparticle–PVC composite films were prepared by solution casting method. ? A low electrical percolation threshold of 2.2 was achieved. ? The low temperature electrical conductivity follows variable range hopping type conduction. ? An EMI shielding of 18 dB was achieved in 200 micron thick film. -- Abstract: In this paper, the low temperature electrical conductivity and microwave absorption properties of carbon coated iron nanoparticles–polyvinyl chloride composite films are investigated for different filler fractions. The filler particles are prepared by the pyrolysis of ferrocene at 980 °C and embedded in polyvinyl chloride matrix. The high resolution transmission electron micrographs of the filler material have shown a 5 nm thin layer graphitic carbon covering over iron particles. The room temperature electrical conductivity of the composite film changes by 10 orders of magnitude with the increase of filler concentration. A percolation threshold of 2.2 and an electromagnetic interference shielding efficiency (EMI SE) of ?18.6 dB in 26.5–40 GHz range are observed for 50 wt% loading. The charge transport follows three dimensional variable range hopping conduction.

  12. A compact micro-wave synthesizer for transportable cold-atom interferometers

    SciTech Connect (OSTI)

    Lautier, J.; Lours, M.; Landragin, A., E-mail: arnaud.landragin@obspm.fr [LNE-SYRTE, Observatoire de Paris, CNRS, UPMC, 61 avenue de l’Observatoire, 75014 Paris (France)

    2014-06-15T23:59:59.000Z

    We present the realization of a compact micro-wave frequency synthesizer for an atom interferometer based on stimulated Raman transitions, applied to transportable inertial sensing. Our set-up is intended to address the hyperfine transitions of {sup 87}Rb at 6.8 GHz. The prototype is evaluated both in the time and the frequency domain by comparison with state-of-the-art frequency references developed at Laboratoire national de métrologie et d'essais?Systémes de référence temps espace (LNE-SYRTE). In free-running mode, it features a residual phase noise level of ?65 dB rad{sup 2} Hz{sup ?1} at 10 Hz offset frequency and a white phase noise level in the order of ?120 dB rad{sup 2} Hz{sup ?1} for Fourier frequencies above 10 kHz. The phase noise effect on the sensitivity of the atomic interferometer is evaluated for diverse values of cycling time, interrogation time, and Raman pulse duration. To our knowledge, the resulting contribution is well below the sensitivity of any demonstrated cold atom inertial sensors based on stimulated Raman transitions. The drastic improvement in terms of size, simplicity, and power consumption paves the way towards field and mobile operations.

  13. A compact micro-wave synthesizer for transportable cold-atom interferometers

    E-Print Network [OSTI]

    Lautier, Jean; Landragin, Arnaud

    2014-01-01T23:59:59.000Z

    We present the realization of a compact micro-wave frequency synthesizer for an atom interferometer based on stimulated Raman transitions, applied to transportable inertial sensing. Our set-up is intended to address the hyperfine transitions of Rubidium 87 atoms at 6.8 GHz. The prototype is evaluated both in the time and the frequency domain by comparison with state-of-the-art frequency references developed at LNE-SYRTE. In free-running mode, it features a residual phase noise level of -65 dBrad$^2.Hz^{-1} at 10-Hz offset frequency and a white phase noise level in the order of -120 dBrad^2.Hz^{-1} for Fourier frequencies above 10 kHz. The phase noise effect on the sensitivity of the atomic interferometer is evaluated for diverse values of cycling time, interrogation time and Raman pulse duration. To our knowledge, the resulting contribution is well below the sensitivity of any demonstrated cold atom inertial sensors based on stimulated Raman transitions. The drastic improvement in terms of size, simplicity an...

  14. A compact micro-wave synthesizer for transportable cold-atom interferometers

    E-Print Network [OSTI]

    Jean Lautier; Michel Lours; Arnaud Landragin

    2014-06-11T23:59:59.000Z

    We present the realization of a compact micro-wave frequency synthesizer for an atom interferometer based on stimulated Raman transitions, applied to transportable inertial sensing. Our set-up is intended to address the hyperfine transitions of Rubidium 87 atoms at 6.8 GHz. The prototype is evaluated both in the time and the frequency domain by comparison with state-of-the-art frequency references developed at LNE-SYRTE. In free-running mode, it features a residual phase noise level of -65 dBrad$^2.Hz^{-1} at 10-Hz offset frequency and a white phase noise level in the order of -120 dBrad^2.Hz^{-1} for Fourier frequencies above 10 kHz. The phase noise effect on the sensitivity of the atomic interferometer is evaluated for diverse values of cycling time, interrogation time and Raman pulse duration. To our knowledge, the resulting contribution is well below the sensitivity of any demonstrated cold atom inertial sensors based on stimulated Raman transitions. The drastic improvement in terms of size, simplicity and power consumption paves the way towards field and mobile operations.

  15. InP HBT Digital ICs and MMICs in the 140-220 GHz band Mark Rodwell, Z. Griffith, V. Paidi, N. Parthasarathy, C. Sheldon, U. Singisetti

    E-Print Network [OSTI]

    Rodwell, Mark J. W.

    , 150 GHz digital circuits (static dividers) and 175 GHz amplifiers have been demonstrated. We discuss, oscillators, mixers, harmonic multipliers, switches, and logic gates. With transistors, one can compactly digital benchmark circuits (static frequency dividers). 172 GHz medium-power amplifiers have been realized

  16. International Conference on Microwave and High Frequency Heating Nottingham, UK, September 2013 Underwater Microwave Ignition of

    E-Print Network [OSTI]

    Jerby, Eli

    -cost operation [4, 5]. Thermite reaction as a self-propagated, high-temperature synthesis (SHS) process, Localized microwave heating, underwater ignition, combustion. INTRODUCTION Self-propagated thermite reactions between metal-oxide and metals typically burn at high flame temperatures, and require high

  17. IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 57, NO. 8, AUGUST 2009 1903 A 2229-GHz UWB Pulse-Radar Receiver

    E-Print Network [OSTI]

    Heydari, Payam

    -assistance and security func- tions including collision avoidance, precise airbag activation, parking assistance, blind

  18. IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 46, NO. 2, FEBRUARY 1998 1 A 850 GHz Waveguide Receiver Employing a

    E-Print Network [OSTI]

    Technology, Jet Propulsion Laboratory, California Institute of Technology, and was sponsored by NASA, Office@tacos.caltech.edu. B. Bumble and H.G. LeDuc are with the Center for Space Micro- electronics Technology, Jet Propulsion by Ellison et al. [1] and employs two circular non-contacting tuning elements [2], [3], magnetic field

  19. 1566 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 49, NO. 9, SEPTEMBER 2001 A 20-GHz InPHBT Voltage-Controlled Oscillator

    E-Print Network [OSTI]

    Voinigescu, Sorin Petre

    , resulting in lower self-heating under bias. Other features of InP HBTs are low noise corner frequency down. Djahanshahi was with the Department of Electrical and Computer Engi- neering, University of Toronto, Toronto. T. Salama are with the Department of Electrical and Computer Engineering, University of Toronto

  20. RF and Microwave Amplifier Design With ESD Protection

    E-Print Network [OSTI]

    Lin, Lin

    2010-01-01T23:59:59.000Z

    A 3.1 to 8.2 GHz direct conversion receiver for MB- OFDM UWBnaturally employ direct conversion, that is, zero-IF.Such a direct conversion 3-band OFDM UWB transceiver has

  1. EXPANDED VERY LARGE ARRAY DETECTION OF 36.2 GHz CLASS I METHANOL MASERS IN SAGITTARIUS A

    SciTech Connect (OSTI)

    Sjouwerman, Lorant O. [National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801 (United States); Pihlstroem, Ylva M. [Department of Physics and Astronomy, University of New Mexico, 800 Yale Boulevard NE, Albuquerque, NM 87131 (United States); Fish, Vincent L. [Massachusetts Institute of Technology, Haystack Observatory, Route 40, Westford, MA 01886 (United States)], E-mail: lsjouwerman@nrao.edu, E-mail: ylva@unm.edu, E-mail: vfish@haystack.mit.edu

    2010-02-20T23:59:59.000Z

    We report on the interferometric detection of 36.2 GHz Class I methanol emission with the new 27-40 GHz Ka-band receivers available on the Expanded Very Large Array (EVLA). The brightness temperatures of the interferometric 36 GHz detections unambiguously indicate for the first time that the emission is maser emission. The 36 GHz methanol masers are not co-spatial with 1720 MHz OH masers, indicating that the two species trace different shocks. The 36 GHz and 44 GHz methanol masers, which are collisionally pumped, do not necessarily co-exist and may trace different methanol gas. The methanol masers seem correlated with NH{sub 3}(3,3) density peaks. We favor an explanation in which the 36 GHz Class I methanol masers outline regions of cloud-cloud collisions, perhaps just before the onset of the formation of individual massive stars. The transition of the Very Large Array (VLA) to the EVLA is well under way, and these detections demonstrate the bright future of this completely renewed instrument.

  2. Using Radar, Lidar, and Radiometer measurements to Classify Cloud Type and Study Middle-Level Cloud Properties

    SciTech Connect (OSTI)

    Wang, Zhien

    2010-06-29T23:59:59.000Z

    The project is mainly focused on the characterization of cloud macrophysical and microphysical properties, especially for mixed-phased clouds and middle level ice clouds by combining radar, lidar, and radiometer measurements available from the ACRF sites. First, an advanced mixed-phase cloud retrieval algorithm will be developed to cover all mixed-phase clouds observed at the ACRF NSA site. The algorithm will be applied to the ACRF NSA observations to generate a long-term arctic mixed-phase cloud product for model validations and arctic mixed-phase cloud processes studies. To improve the representation of arctic mixed-phase clouds in GCMs, an advanced understanding of mixed-phase cloud processes is needed. By combining retrieved mixed-phase cloud microphysical properties with in situ data and large-scale meteorological data, the project aim to better understand the generations of ice crystals in supercooled water clouds, the maintenance mechanisms of the arctic mixed-phase clouds, and their connections with large-scale dynamics. The project will try to develop a new retrieval algorithm to study more complex mixed-phase clouds observed at the ACRF SGP site. Compared with optically thin ice clouds, optically thick middle level ice clouds are less studied because of limited available tools. The project will develop a new two wavelength radar technique for optically thick ice cloud study at SGP site by combining the MMCR with the W-band radar measurements. With this new algorithm, the SGP site will have a better capability to study all ice clouds. Another area of the proposal is to generate long-term cloud type classification product for the multiple ACRF sites. The cloud type classification product will not only facilitates the generation of the integrated cloud product by applying different retrieval algorithms to different types of clouds operationally, but will also support other research to better understand cloud properties and to validate model simulations. The ultimate goal is to improve our cloud classification algorithm into a VAP.

  3. Microwave sintering of sol-gel derived abrasive grain

    DOE Patents [OSTI]

    Plovnick, Ross (St. Louis Park, MN); Celikkaya, Ahmet (Woodbury, MN); Blake, Rodger D. (Tuscon, AZ)

    1997-01-01T23:59:59.000Z

    A method is provided for making microwave-sintered, free flowing alpha alumina-based ceramic abrasive grain, under conditions effective to couple microwaves with calcined alpha alumina-based abrasive gain precursor and sinter it at a temperature of at least about 1150.degree. C.

  4. CAD OF MICROWAVE OPTICAL SYSTEMS FOR TIME&FREQUENCY APPLICATIONS

    E-Print Network [OSTI]

    Boyer, Edmond

    or their impact on the phase noise. II- SIMULATION OF AN MZ BASED OPTICAL LINK: RF GAIN Microwave circuit designCAD OF MICROWAVE OPTICAL SYSTEMS FOR TIME&FREQUENCY APPLICATIONS Houda Brahimi, LAAS-CNRS, Toulouse are more and more involved in time and frequency applications. They may be used for frequency reference

  5. Temperature Modeling for Reaction Development in Microwave-Assisted Chemistry

    E-Print Network [OSTI]

    Yakovlev, Vadim

    of exposure of the reactants to the electromagnetic (EM) field. The microwave parts of those systems are-scale resonator-type reactor in a 3D model capable of monitoring electromagnetic and thermal processes field. I. INTRODUCTION Microwave-assisted chemistry has recently emerged as a rapidly growing field

  6. Microwave Melting | Y-12 National Security Complex

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |IsLove Your1 SECTION A. Revised:7, at 3:00 pmYourMicrowave Melting

  7. Manipulating microwaves with magnetic-dipolar-mode vortices

    SciTech Connect (OSTI)

    Kamenetskii, E. O.; Sigalov, M.; Shavit, R. [Department of Electrical and Computer Engineering, Ben Gurion University of the Negev, IL-84 105 Beer Sheva (Israel)

    2010-05-15T23:59:59.000Z

    There has been a surge of interest in the subwavelength confinement of electromagnetic fields. It is well known that, in optics, subwavelength confinement can be obtained from surface plasmon (quasielectrostatic) oscillations. In this article, we propose to realize subwavelength confinement in microwaves by using dipolar-mode (quasimagnetostatic) magnon oscillations in ferrite particles. Our studies of interactions between microwave electromagnetic fields and small ferrite particles with magnetic-dipolar-mode (MDM) oscillations show strong localization of electromagnetic energy. MDM oscillations in a ferrite disk are at the origin of topological singularities resulting in Poynting vector vortices and symmetry breakings of the microwave near fields. We show that new subwavelength microwave structures can be realized based on a system of interacting MDM ferrite disks. Wave propagation of electromagnetic signals in such structures is characterized by topological phase variations. Interactions of microwave fields with an MDM ferrite disk and MDM-disk arrays open a perspective for creating engineered electromagnetic fields with unique symmetry properties.

  8. Microwave characterization of high-temperature superconductors

    SciTech Connect (OSTI)

    Cooke, D.W.; Gray, E.R.; Arendt, P.N.; Beery, J.G.; Bennett, B.L.; Brown, D.R.; Houlton, R.J.; Jahan, M.S.; Klapetzky, A.J.; Maez, M.A.; Raistrick, I.D.; Reeves, G.A.; Rusnak, B.

    1989-01-01T23:59:59.000Z

    Thick (10-15 {mu}m) Tl-Ba-Ca-Cu-O films have been deposited onto yttria-stabilized zirconia and Ag substrates by d.c. magnetron sputtering techniques. Direct deposition onto 1'' diameter yttria-stabilized zirconia yields films with typical 22 GHz surface resistance (R{sub s}) values of 5.2 {plus minus} 2 m{Omega} and 52 {plus minus} 2 m{Omega} at 10 K and 77 K, respectively. For comparison, R{sub s} of Cu at this same frequency is 10 m{Omega} at 4 K and 22 m{Omega} at 77 K. Tl-Ba-Ca-Cu-O films have also been deposited onto 1'' diameter Ag substrates using Au/Cu, Cu, and BaF{sub 2} buffer layers. The lowest R{sub s} values were obtained on films with a BaF{sub 2} buffer layer, typical values being 7.8 {plus minus} 2 m{Omega} and 30.6 {plus minus} 2 m{Omega} (measured at 22 GHz) at 10 K and 77 K, respectively. Larger films (1.5'' diameter) with similar R{sub s} values were prepared using this same technique, demonstrating that the fabrication process can be scaled to larger surface areas. These films are promising for radiofrequency cavity applications because they are thick (50-75 times the London penetration depth), have relatively large surface areas, are fabricated on metallic substrates, and have R{sub s} values that are competitive with Cu at 77 K and are lower than Cu at 4 K. Because they are polycrystalline and unoriented, it is anticipated that their R{sub s} values can be lowered by improving the processing technique. High-quality films of YBa{sub 2}Cu{sub 3}O{sub 7} have been electron-beam deposited onto 1'' LaGaO{sub 3} and 1.5'' LaAlO{sub 3} substrates. The 1'' sample is characterized by R{sub s} values of 0.2 {plus minus} 0.1 m{Omega} at 4 K and 18.6 {plus minus} 2 m{Omega} at 77 K. The 4-K value is only 2-4 times higher than Nb. The 1.5'' sample has R{sub s} values (measured at 18 GHz) of 0.93 {plus minus} 2 m{Omega} and 71 {plus minus} 3 m{Omega} at 10 K and 77 K, respectively. 18 refs., 8 figs.

  9. Radiometer Calibration Trends

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection Radiation Protection Regulations:Radiological Threat Reduction

  10. Radiometer Characterization System

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection Radiation Protection Regulations:Radiological Threat Reduction2

  11. A Novel Retrieval Algorithm for Cloud Optical Properties from the Atmopsheric Radiation Measurement Program's Two-Channel Narrow-Field-of-View Radiometer

    SciTech Connect (OSTI)

    Wiscombe, Warren J.; Marshak, A.; Chiu, J.-Y. C.; Knyazikhin, Y.; Barnard, James C.; Luo, Yi

    2005-03-14T23:59:59.000Z

    Cloud optical depth is the most important of all cloud optical properties, and vital for any cloud-radiation parameterization. To estimate cloud optical depth, the atmospheric science community has widely used ground-based flux measurements from either broadband or narrowband radiometers in the past decade. However, this type of technique is limited to overcast conditions and, at best, gives us an "effective" cloud optical depth instead of its "local" value. Unlike flux observations, monochromatic narrow-field-of-view (NFOV) radiance measurements contain information of local cloud properties, but unfortunately, the use of radiance to interpret optical depth suffers from retrieval ambiguity. We have pioneered an algorithm to retrieve cloud optical depth in a fully three-dimensional cloud situation using new Atmospheric Radiation Measurement (ARM) ground-based passive two-channel (673 and 870 nm) NFOV measurements. The underlying principle of the algorithm is that these two channels have similar cloud properties but strong spectral contrast in surface reflectance. This algorthm offers the first opportunity to illustrate cloud evolution with high temporal resolution retrievals. A combination of two-channel NFOV radiances with multi-filter rotating shadowband radiometer (MFRSR) fluxes for the retrieval of cloud optical properties is also discussed.

  12. PHYSICAL CONDITIONS AROUND 6.7 GHz METHANOL MASERS. I. AMMONIA

    SciTech Connect (OSTI)

    Pandian, J. D. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Dr., Honolulu, HI 96822 (United States); Wyrowski, F.; Menten, K. M., E-mail: jagadheep@iist.ac.in [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, 53121 Bonn (Germany)

    2012-07-01T23:59:59.000Z

    Methanol masers at 6.7 GHz are known to be tracers of high-mass star formation in our Galaxy. In this paper, we study the large-scale physical conditions in the star-forming clumps/cores associated with 6.7 GHz methanol masers using observations of the (1, 1), (2, 2), and (3, 3) inversion transitions of ammonia with the Effelsberg telescope. The gas kinetic temperature is found to be higher than in infrared dark clouds, highlighting the relatively evolved nature of the maser sources. Other than a weak correlation between maser luminosity and the ammonia line width, we do not find any differences between low- and high-luminosity methanol masers.

  13. A high-sensitivity 6.7 GHz methanol maser survey toward H2O sources

    E-Print Network [OSTI]

    Y. Xu; J. J. Li; K. Hachisuka; J. D. Pandian; K. M. Menten; C. Henkel

    2008-03-16T23:59:59.000Z

    We present the results of a high sensitivity survey for 6.7 GHz methanol masers towards 22 GHz water maser using the 100 m Efflesberg telescope. A total of 89 sources were observed and 10 new methanol masers were detected. The new detections are relatively faint with peak flux densities between 0.5 and 4.0 Jy. A nil detection rate from low-mass star forming regions enhances the conclusion that the masers are only associated with massive star formation. Even the faintest methanol maser in our survey, with a luminosity of 1.1 $10^{-9} L_\\odot$ is associated with massive stars as inferred from its infrared luminosity.

  14. Radio observations of the first three-month Fermi-AGN at 4.8 GHz

    E-Print Network [OSTI]

    Xiang Liu; Hua-Gang Song; Jun Liu; Zhen Ding; Nicola Marchili; Thomas P. Krichbaum; Lars Fuhrmann; Anton Zensus; Tao An

    2011-10-09T23:59:59.000Z

    Using the Urumqi 25m radio telescope, sources from the first three-month Fermi-LAT detected AGN catalog with declination >0 were observed in 2009 at 4.8 GHz. The radio flux density appears to correlate with the gamma-ray intensity. Intra-day variability (IDV) observations were performed in March, April and May in 2009 for selected 42 gamma-ray bright blazars, and 60% of them show evident flux variability at 4.8 GHz during the IDV observations, the IDV detection rate is higher than that in previous flat-spectrum AGN samples. The IDV appears more often in the VLBI-core dominant blazars, and the non-IDV blazars show relatively `steeper' spectral indices than the IDV blazars. Pronounced inter-month variability has been found in two BL Lac objects: J0112+2244 and J0238+1636.

  15. Astrometry of the stellar image of U Her amplified by the circumstellar 22 GHz water masers

    E-Print Network [OSTI]

    W. H. T. Vlemmings; H. J. van Langevelde; P. J. Diamond

    2002-08-09T23:59:59.000Z

    The 22 GHz H_2O masers in the circumstellar envelope of the Mira variable star U Her have been observed with MERLIN using a phase referencing technique to determine accurate astrometric positions. The positions were compared with the optical positions obtained with the Hipparcos satellite to an accuracy of 18 mas. The absolute radio position of the brightest H_2O maser spot is found to match the optical position, indicating that this spot is the stellar image amplified by the maser screen in front of it. The occurrence of an amplified image in the 22 GHz maser can be used to accurately determine the positions of the H_2O with respect to the star as well as with respect to the SiO and OH masers. Our observations seem to indicate that the star is not in the centre of the distribution of maser spots, which has been interpreted as a ring.

  16. BEHAVIOUR OF A HIGHLY PRESSURISED TANK OF GHz, SUBMITTED TO A THERMAL OR MECHANICAL IMPACT

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of 40 bar, the hydrogen mass flow would be 0,23 g/s, which is the minimum flow needed by the engine may limit a fast and large increase in the use of GHz äs a füel for engines in the füture. Furthermore. The thermal füse opens at 80°C. These safety devices have been fitted to the pipe supplying hydrogen from

  17. Making Maps from Planck LFI 30GHz Data with Asymmetric Beams and Cooler Noise

    SciTech Connect (OSTI)

    The Planck CTP Working Group; Ashdown, M.A.J.; Baccigalupi, C.; Bartlett, J.G.; Borrill, J.; Cantalupo, C.; de Gasperis, G.; Gorski, K.M.; Hivon, E.; Huffenberger, K.; Keihanen, E.; Keskitalo, R.; Kisner, T.; Hurki-Suonio, H.; Lawrence, C.R.; Natoli, P.; Poutanen, T.; Prezeau, G.; Reinecke, M.; Rocha, G.; Sandri, M.; Stompor, R..; Villa, F.; Wandelt, B.; de Troia, G.

    2008-06-19T23:59:59.000Z

    The Planck satellite will observe the full sky at nine frequencies from 30 to 857 GHz. Temperature and polarization frequency maps made from these observations are prime deliverables of the Planck mission. The goal of this paper is to examine the effects of four realistic instrument systematics in the 30 GHz frequency maps: non-axially-symmetric beams, sample integration, sorption cooler noise, and pointing errors. They simulated one year long observations of four 30 GHz detectors. The simulated timestreams contained CMB, foreground component (both galactic and extra-galactic), instrument nolise (correlated and white), and the four instrument systematic effects. They made maps from the timelines and examined the magnitudes of the systematics effects in the maps and their angular power spectra. They also compared the maps of different mapmaking codes to see how they performed. They used five mapmaking codes (two destripers and three optimal codes). None of their mapmaking codes makes an attempt to deconvolve the beam from its output map. Therefore all our maps had similar smoothing due to beams and sample integration. This is a complicated smoothing, because every map pixel has its own effective beam. Temperature to polarization cross-coupling due to beam mismatch causes a detectable bias in the TE spectrum of the CMB map. The effects of cooler noise and pointing errors did not appear to be major concerns for the 30 GHz channel. The only essential difference found so far between mapmaking codes that affects accuracy (in terms of residual RMS) is baseline length. All optimal codes give essentially indistiguishable results. A destriper gives the same result as the optimal codes when the baseline is set short enough (Madam). For longer baselines destripers (Springtide and Madam) require less computing resources but deliver a noisier map.

  18. Microphonics detuning compensation in 3.9 GHZ superconducting RF cavities

    SciTech Connect (OSTI)

    Ruben Carcagno et al.

    2003-10-20T23:59:59.000Z

    Mechanical vibrations can detune superconducting radio frequency (SCRF) cavities unless a tuning mechanism counteracting the vibrations is present. Due to their narrow operating bandwidth and demanding mechanical structure, the 13-cell 3.9GHz SCRF cavities for the Charged Kaons at Main Injector (CKM) experiment at Fermilab are especially susceptible to this microphonic phenomena. We present early results correlating RF frequency detuning with cavity vibration measurements for CKM cavities; initial detuning compensation results with piezoelectric actuators are also presented.

  19. A Low-Voltage 77-GHz Automotive Radar Chipset Sean T. Nicolson1

    E-Print Network [OSTI]

    Voinigescu, Sorin Petre

    (VCO, LNA, PA, mixer, and static frequency divider) required to fabricate a fully integrated 2.5V, 77-noise amplifier, a novel low-voltage double-balanced Gilbert-cell mixer with two mm-wave baluns and IF amplifier achieving 12.8dB noise figure and an OP1dB of +5dBm, a 99GHz static frequency divider consuming a record low

  20. Pattern formation and propagation during microwave breakdown

    SciTech Connect (OSTI)

    Chaudhury, Bhaskar [Laboratoire Plasma et Conversion d'Energie (LAPLACE), INPT, UPS, Universite de Toulouse, 118 route de Narbonne, F-31062 Toulouse Cedex 9 (France); Boeuf, Jean-Pierre [Laboratoire Plasma et Conversion d'Energie (LAPLACE), INPT, UPS, Universite de Toulouse, 118 route de Narbonne, F-31062 Toulouse Cedex 9 (France); LAPLACE, CNRS, F-31062 Toulouse (France); Zhu, Guo Qiang [Laboratoire Plasma et Conversion d'Energie (LAPLACE), INPT, UPS, Universite de Toulouse, 118 route de Narbonne, F-31062 Toulouse Cedex 9 (France); Northwestern Polytechnique University, Xi'an 710072 (China)

    2010-12-15T23:59:59.000Z

    During microwave breakdown at atmospheric pressure, a sharp plasma front forms and propagates toward the microwave source at high velocities. Experiments show that the plasma front may exhibit a complex dynamical structure or pattern composed of plasma filaments aligned with the wave electric field and apparently moving toward the source. In this paper, we present a model of the pattern formation and propagation under conditions close to recent experiments. Maxwell's equations are solved together with plasma fluid equations in two dimensions to describe the space and time evolution of the wave field and plasma density. The simulation results are in excellent agreement with the experimental observations. The model provides a physical interpretation of the pattern formation and dynamics in terms of ionization-diffusion and absorption-reflection mechanisms. The simulations allow a good qualitative and quantitative understanding of different features such as plasma front velocity, spacing between filaments, maximum plasma density in the filaments, and influence of the discharge parameters on the development of well-defined filamentary plasma arrays or more diffuse plasma fronts.

  1. Microwaves, hyperthermia, and human leukocyte function

    SciTech Connect (OSTI)

    Roberts, N.J. Jr; Lu, S.; Michaelson, S.M.

    1981-05-01T23:59:59.000Z

    The objective of this study is to determine whether exposure to microwaves (2450 MHz) affects the function of human leukocytes in the resting state and during antigenic or mitogenic challenge. This publication is a summary report of the construction and calibration of a waveguide exposure facility for in vitro irradiation of human leukocytes. Calorimetric determinations of specific absorption rates (SAR) were made using heating curves measured with a microwave transparent Vitek 101 Electrothermia Monitor. The correlation between SAR and forward power was highly significant (r=0.95). At a forward power of 0.55 W the average SAR was approximately 33 mW/ml. However, inhomogeneity and significant resonance absorption were noted in the dual vial waveguide exposure facility. A 30-point measurement of SAR distribution revealed that the SAR at any of the measured points could range between 0.12- and 3.94-fold of the average SAR within the given vial. Measurements indicated that this variability in SAR values did not create significant thermal gradients within the vials when external agitation was applied.

  2. Analysis and control of the thermal runaway of ceramic slab under microwave heating

    E-Print Network [OSTI]

    Sheen, Dongwoo

    Analysis and control of the thermal runaway of ceramic slab under microwave heating Changjun Liu of the dielectrics during microwave heating, in which there is a big jump of the steady-state temperature while the applied microwave power varies slightly. It hinders engineers in the applications of microwave heating

  3. 11-GHz direct modulation bandwidth GaAlAs window laser on semi-insulating substrate operating at room temperature

    SciTech Connect (OSTI)

    Lau, K.Y.; Bar-Chaim, N.; Ury, I.; Yariv, A.

    1984-08-15T23:59:59.000Z

    We have demonstrated a direct modulation bandwidth of up to 11 GHz in a window GaAlAs buried heterostructure laser fabricated on a semi-insulating substrate, operating at room temperature.

  4. Functional and shunt states of bacteriorhodopsin resolved by 250 GHz dynamic nuclear polarization-enhanced solid-state NMR

    E-Print Network [OSTI]

    Bajaj, Vikram S.

    Observation and structural studies of reaction intermediates of proteins are challenging because of the mixtures of states usually present at low concentrations. Here, we use a 250 GHz gyrotron (cyclotron resonance maser) ...

  5. High spectral purity 26 GHz oscillator based on a SiO2 Whispering Gallery Mode Resonator

    E-Print Network [OSTI]

    Boyer, Edmond

    for the achievement of low phase noise microwave source . Introduction : Achievement of low phase noise microwave(f) is dominated by flicker phase noise (1/f noise) at low Fourier frequencies, S(f) shows flicker frequency noise to reach low phase noise performances. Ultrahigh Q values can be obtained with sapphire (Al2O3 monocrystal

  6. Portable microwave instrument for non-destructive evaluation of structural characteristics

    DOE Patents [OSTI]

    Bible, Don W. (Clinton, TN); Crutcher, Richard I. (Knoxville, TN); Sohns, Carl W. (Oak Ridge, TN); Maddox, Stephen R. (Loudon, TN)

    1995-01-01T23:59:59.000Z

    A portable microwave instrument for evaluating characteristics of a structural member includes a source of microwave energy, a transmitter coupled to the source of microwave energy for transmitting a microwave signal at the structural member, and a receiver positioned on the same side of the structural member as the transmitter and being disposed to receive a microwave signal reflected by the structural member. A phase angle difference is determined between the transmitted microwave signal and the received microwave signal using a signal splitter and a balanced mixer. The difference in phase angle varies in accordance with differences in size, shape and locations of constituent materials within the structural member.

  7. Portable microwave instrument for non-destructive evaluation of structural characteristics

    DOE Patents [OSTI]

    Bible, D.W.; Crutcher, R.I.; Sohns, C.W.; Maddox, S.R.

    1995-01-24T23:59:59.000Z

    A portable microwave instrument for evaluating characteristics of a structural member includes a source of microwave energy, a transmitter coupled to the source of microwave energy for transmitting a microwave signal at the structural member, and a receiver positioned on the same side of the structural member as the transmitter and being disposed to receive a microwave signal reflected by the structural member. A phase angle difference is determined between the transmitted microwave signal and the received microwave signal using a signal splitter and a balanced mixer. The difference in phase angle varies in accordance with differences in size, shape and locations of constituent materials within the structural member. 6 figures.

  8. mm-WAVE Op-Amps FOR LOW DISTORTION AMPLIFICATION WITH HIGH OIP3/PDC RATIO > 100 AT 2 GHz

    E-Print Network [OSTI]

    Rodwell, Mark J. W.

    mm-WAVE Op-Amps FOR LOW DISTORTION AMPLIFICATION WITH HIGH OIP3/PDC RATIO > 100 AT 2 GHz Zach in bandwidth for an op-amp of any kind, as well as 3Ã? betterment in OIP3/PDC ratio at fs = 2-3 GHz, when dissipation PDC. This very high ratio of third-order-intercept power to DC power consumption POIP 3/PDC > 100

  9. Passive and active circuits in cmos technology for rf, microwave and millimeter wave applications

    E-Print Network [OSTI]

    Chirala, Mohan Krishna

    2009-05-15T23:59:59.000Z

    being suitably tailored for CMOS technology. A number of novel passive structures - including a compact 10 GHz hairpin resonator, a broadband, low loss 25-35 GHz Lange coupler, a 25-35 GHz thin film microstrip (TFMS) ring hybrid, an array of 0.8 nH and 0...

  10. Method and apparatus for component separation using microwave energy

    DOE Patents [OSTI]

    Morrow, Marvin S. (Kingston, TN); Schechter, Donald E. (Ten Mile, TN); Calhoun, Jr., Clyde L. (Knoxville, TN)

    2001-04-03T23:59:59.000Z

    A method for separating and recovering components includes the steps of providing at least a first component bonded to a second component by a microwave absorbent adhesive bonding material at a bonding area to form an assembly, the bonding material disposed between the components. Microwave energy is directly and selectively applied to the assembly so that substantially only the bonding material absorbs the microwave energy until the bonding material is at a debonding state. A separation force is applied while the bonding material is at the debonding state to permit disengaging and recovering the components. In addition, an apparatus for practicing the method includes holders for the components.

  11. Electron beam collector for a microwave power tube

    DOE Patents [OSTI]

    Dandl, Raphael A. (Oak Ridge, TN)

    1980-01-01T23:59:59.000Z

    This invention relates to a cylindrical, electron beam collector that efficiently couples the microwave energy out of a high power microwave source while stopping the attendant electron beam. The interior end walls of the collector are a pair of facing parabolic mirrors and the microwave energy from an input horn is radiated between the two mirrors and reassembled at the entrance to the output waveguide where the transmitted mode is reconstructed. The mode transmission through the collector of the present invention has an efficiency of at least 94%.

  12. Electrical detection of microwave assisted magnetization reversal by spin pumping

    SciTech Connect (OSTI)

    Rao, Siddharth; Subhra Mukherjee, Sankha; Elyasi, Mehrdad; Singh Bhatia, Charanjit; Yang, Hyunsoo, E-mail: eleyang@nus.edu.sg [Department of Electrical and Computer Engineering and NUSNNI, National University of Singapore, Singapore 117576 (Singapore)

    2014-03-24T23:59:59.000Z

    Microwave assisted magnetization reversal has been investigated in a bilayer system of Pt/ferromagnet by detecting a change in the polarity of the spin pumping signal. The reversal process is studied in two material systems, Pt/CoFeB and Pt/NiFe, for different aspect ratios. The onset of the switching behavior is indicated by a sharp transition in the spin pumping voltage. At a threshold value of the external field, the switching process changes from partial to full reversal with increasing microwave power. The proposed method provides a simple way to detect microwave assisted magnetization reversal.

  13. 2D microwave imaging reflectometer electronics

    SciTech Connect (OSTI)

    Spear, A. G.; Domier, C. W., E-mail: cwdomier@ucdavis.edu; Hu, X.; Muscatello, C. M.; Ren, X.; Luhmann, N. C. [Electrical and Computer Engineering, University of California, Davis, California 95616 (United States); Tobias, B. J. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

    2014-11-15T23:59:59.000Z

    A 2D microwave imaging reflectometer system has been developed to visualize electron density fluctuations on the DIII-D tokamak. Simultaneously illuminated at four probe frequencies, large aperture optics image reflections from four density-dependent cutoff surfaces in the plasma over an extended region of the DIII-D plasma. Localized density fluctuations in the vicinity of the plasma cutoff surfaces modulate the plasma reflections, yielding a 2D image of electron density fluctuations. Details are presented of the receiver down conversion electronics that generate the in-phase (I) and quadrature (Q) reflectometer signals from which 2D density fluctuation data are obtained. Also presented are details on the control system and backplane used to manage the electronics as well as an introduction to the computer based control program.

  14. Quantum chaotic scattering in microwave resonators

    SciTech Connect (OSTI)

    Dietz, B.; Miski-Oglu, M.; Schaefer, F. [Institut fuer Kernphysik, Technische Universitaet Darmstadt, D-64289 Darmstadt (Germany); Friedrich, T. [Institut fuer Kernphysik, Technische Universitaet Darmstadt, D-64289 Darmstadt (Germany); GSI Helmholzzentrum fuer Schwerionenforschung GmbH, D-64291 Darmstadt (Germany); Harney, H. L.; Weidenmueller, H. A. [Max-Planck-Institut fuer Kernphysik, D-69029 Heidelberg (Germany); Richter, A. [Institut fuer Kernphysik, Technische Universitaet Darmstadt, D-64289 Darmstadt (Germany); ECT, Villa Tambosi, I-38100 Villazzano (Trento) (Italy)

    2010-03-15T23:59:59.000Z

    In a frequency range where a microwave resonator simulates a chaotic quantum billiard, we have measured moduli and phases of reflection and transmission amplitudes in the regimes of both isolated and of weakly overlapping resonances and for resonators with and without time-reversal invariance. Statistical measures for S-matrix fluctuations were determined from the data and compared with extant and/or newly derived theoretical results obtained from the random-matrix approach to quantum chaotic scattering. The latter contained a small number of fit parameters. The large data sets taken made it possible to test the theoretical expressions with unprecedented accuracy. The theory is confirmed by both a goodness-of-fit-test and the agreement of predicted values for those statistical measures that were not used for the fits, with the data.

  15. Microwave-Regenerated Diesel Exhaust Particulate Filter

    SciTech Connect (OSTI)

    Nixdorf, Richard D. (Industrial Ceramic Solution, LLC); Green, Johney Boyd; Story, John M.; Wagner, Robert M. (Oak Ridge National Laboratory)

    2001-03-05T23:59:59.000Z

    Development of a microwave-regenerated particulate filter system has evolved from bench scale work to actual diesel engine experimentation. The filter system was initially evaluated on a stationary mounted 1.2-L diesel engine and was able to remove a significant amount of carbon particles from the exhaust. The ability of the microwave energy to regenerate or clean the filter was also demonstrated on this engine under idle conditions. Based on the 1.2-L experiments, improvements to the filter design and materials were implemented and the system was re-evaluated on a vehicle equipped with a 7.3-L diesel engine. The 7.3-L engine was selected to achieve heavy filter loading in a relatively short period of time. The purpose of these experiments was to evaluate filter-loading capacity, power requirements for regeneration, and filter regeneration efficiency. A more detailed evaluation of the filter was performed on a stationary mounted 1.9-L diesel engine. The effect of exhaust flow rate, loading, transients, and regeneration on filter efficiency was evaluated with this setup. In addition, gaseous exhaust emissions were investigated with and without an oxidation catalyst on the filter cartridge during loading and regeneration. (SAE Paper SAE-2001-01-0903 © 2001 SAE International. This paper is published on this website with permission from SAE International. As a user of this website, you are permitted to view this paper on-line, download this pdf file and print one copy of this paper at no cost for your use only. The downloaded pdf file and printout of this SAE paper may not be copied, distributed or forwarded to others or for the use of others.)

  16. Microwave-Assisted Synthesis of Fluorescent Carbon Nanoparticles

    E-Print Network [OSTI]

    Chen, Bonnie

    2014-08-19T23:59:59.000Z

    . Here, we explore an innovative and simple microwave-assisted synthesis for the production of CNPs from glucose. This method can control tunable emission and the excitation wavelength of CNPs by manufacturing of output energy during synthesis. Moreover...

  17. analogue microwave photonics: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in the microwave range, caused by free-electron collisions with neutrals in the tenuous plasma left after the passage of the shower. We performed an initial experiment at the AWA...

  18. assisted microwave synthesis: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    , and Y. Aharonia,b a Faculty of Engineering, Tel (such as cutting, joining, combustion, plasma generation, etc.) in a wider scope of localized microwave Jerby, Eli 38 Elemental...

  19. Microwave-induced thermoacoustic tomography: reconstruction by synthetic aperture

    E-Print Network [OSTI]

    Feng, Dazi

    2001-01-01T23:59:59.000Z

    was applied for image reconstruction. We greatly improved the lateral resolution of images and acquired a clear view of the circular boundaries of buried cylindrical objects, which could not be obtained in conventional linear-scanning microwave...

  20. Analytical scanning evanescent microwave microscope and control stage

    DOE Patents [OSTI]

    Xiang, Xiao-Dong; Gao, Chen; Duewer, Fred; Yang, Hai Tao; Lu, Yalin

    2013-01-22T23:59:59.000Z

    A scanning evanescent microwave microscope (SEMM) that uses near-field evanescent electromagnetic waves to probe sample properties is disclosed. The SEMM is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The SEMM has the ability to map dielectric constant, loss tangent, conductivity, electrical impedance, and other electrical parameters of materials. Such properties are then used to provide distance control over a wide range, from to microns to nanometers, over dielectric and conductive samples for a scanned evanescent microwave probe, which enable quantitative non-contact and submicron spatial resolution topographic and electrical impedance profiling of dielectric, nonlinear dielectric and conductive materials. The invention also allows quantitative estimation of microwave impedance using signals obtained by the scanned evanescent microwave probe and quasistatic approximation modeling. The SEMM can be used to measure electrical properties of both dielectric and electrically conducting materials.

  1. Uncertainty of microwave radiative transfer computations in rain

    E-Print Network [OSTI]

    Hong, Sung Wook

    2009-06-02T23:59:59.000Z

    of the vertical resolution effect on the BT. Secondly, a new temperature profile based on observations was absorbed in the Texas A&M University (TAMU) algorithm. The Precipitation Radar (PR) and Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI...

  2. Compact hot-nozzle fourier-transform microwave spectormeter

    E-Print Network [OSTI]

    Harmony, Marlin D.; Ratzlaff, Kenneth L.; Angst, D. M.; Beren, K. A.

    1995-11-01T23:59:59.000Z

    A newly constructed pulsed nozzle, Fourier-transform microwave spectrometer utilizes a Fabry-Perot cavity consisting of spherical resonators having diameters of only 10 cm. Tests of this very compact-cavity system show ...

  3. Analytical scanning evanescent microwave microscope and control stage

    DOE Patents [OSTI]

    Xiang, Xiao-Dong (Danville, CA); Gao, Chen (Anhui, CN); Duewer, Fred (Albany, CA); Yang, Hai Tao (Albany, CA); Lu, Yalin (Chelmsford, MA)

    2009-06-23T23:59:59.000Z

    A scanning evanescent microwave microscope (SEMM) that uses near-field evanescent electromagnetic waves to probe sample properties is disclosed. The SEMM is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The SEMM has the ability to map dielectric constant, loss tangent, conductivity, electrical impedance, and other electrical parameters of materials. Such properties are then used to provide distance control over a wide range, from to microns to nanometers, over dielectric and conductive samples for a scanned evanescent microwave probe, which enable quantitative non-contact and submicron spatial resolution topographic and electrical impedance profiling of dielectric, nonlinear dielectric and conductive materials. The invention also allows quantitative estimation of microwave impedance using signals obtained by the scanned evanescent microwave probe and quasistatic approximation modeling. The SEMM can be used to measure electrical properties of both dielectric and electrically conducting materials.

  4. An Efficient Microwave Power Source: Free-electron Laser Afterburner

    E-Print Network [OSTI]

    Wang, C.

    2008-01-01T23:59:59.000Z

    1. Block diagram of the free-electron laser afterburner. The2. The particular free-electron laser afterburner with aMicrowave Power Source: Free-Electron Laser Afterburner c.

  5. Microwave-induced thermoacoustic tomography: reconstruction by synthetic aperture 

    E-Print Network [OSTI]

    Feng, Dazi

    2001-01-01T23:59:59.000Z

    We have applied the synthetic-aperture method to linear-scanning microwave-induced thermoacoustic tomography in biological tissues. A non-focused ultrasonic transducer was used to receive thermoacoustic signals, to which the delay-and-sum algorithm...

  6. Integrating giant microwave absorption with magnetic refrigeration in one

    E-Print Network [OSTI]

    Wang, Wei Hua

    Integrating giant microwave absorption with magnetic refrigeration in one multifunctional with magnetic refrigeration in one multifunctional material. This integration not only advances our-compression/expansion refrigeration, magnetic refrigeration exhibits the advantages of high energy efficiency and environment

  7. Investigation of Nanoparticles for Use in Microwave Systems in Biomedicine 

    E-Print Network [OSTI]

    Taghavi, Houra

    2013-04-30T23:59:59.000Z

    This research focuses on the microwave properties of nanoparticles for use as contrast and hyperthermia agents. Currently, visible light is used for irradiation of nanoparticles as hyperthermia agents. Additionally, visible/Near-infrared light...

  8. Applying Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) spectral indices for geological mapping and mineral identification on the Tibetan Plateau

    E-Print Network [OSTI]

    Corrie, Robert; Aitchison, Jonathan

    2011-01-01T23:59:59.000Z

    The Tibetan Plateau holds clues to understanding the dynamics and mechanisms associated with continental growth. Part of the region is characterized by zones of ophiolitic melange believed to represent the remnants of ancient oceanic crust and underlying upper mantle emplaced during oceanic closures. However, due to the remoteness of the region and the inhospitable terrain many areas have not received detailed investigation. Increased spatial and spectral resolution of satellite sensors have made it possible to map in greater detail the mineralogy and lithology than in the past. Recent work by Yoshiki Ninomiya of the Geological Survey of Japan has pioneered the use of several spectral indices for the mapping of quartzose, carbonate, and silicate rocks using Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) thermal infrared (TIR) data. In this study, ASTER TIR indices have been applied to a region in western-central Tibet for the purposes of assessing their effectiveness for differentiatin...

  9. Two-port microwave calibration at millikelvin temperatures

    SciTech Connect (OSTI)

    Ranzani, Leonardo; Spietz, Lafe; Aumentado, Jose [National Institute of Standards and Technology, Boulder, Colorado 80305 (United States); Popovic, Zoya [University of Colorado at Boulder, Boulder, Colorado 80309 (United States)

    2013-03-15T23:59:59.000Z

    In this work we introduce a system for 2-port microwave calibration at millikelvin temperatures operating at the coldest stage of a dilution refrigerator by use of an adapted thru-reflect-line algorithm. We show that this can be an effective tool for characterizing common 50 {Omega} microwave components with better than 0.1 dB accuracy at temperatures that are relevant to many current experiments in superconducting quantum information.

  10. Fuel gas production by microwave plasma in liquid

    SciTech Connect (OSTI)

    Nomura, Shinfuku; Toyota, Hiromichi; Tawara, Michinaga; Yamashita, Hiroshi; Matsumoto, Kenya [Graduate School of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime 790-8577 (Japan); Shikoku Industry and Technology Promotion Center, 2-5 Marunouchi, Takamatsu, Kagawa 760-0033 (Japan)

    2006-06-05T23:59:59.000Z

    We propose to apply plasma in liquid to replace gas-phase plasma because we expect much higher reaction rates for the chemical deposition of plasma in liquid than for chemical vapor deposition. A reactor for producing microwave plasma in a liquid could produce plasma in hydrocarbon liquids and waste oils. Generated gases consist of up to 81% hydrogen by volume. We confirmed that fuel gases such as methane and ethylene can be produced by microwave plasma in liquid.

  11. Numerical analysis of a microwave torch with axial gas injection

    SciTech Connect (OSTI)

    Gritsinin, S. I.; Davydov, A. M.; Kossyi, I. A., E-mail: kossyi@fpl.gpi.ru [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation); Kulumbaev, E. B. [National Research University Belgorod State University (Russian Federation)] [National Research University Belgorod State University (Russian Federation); Lelevkin, V. M. [Kyrgyz-Russian Slavic University (Kyrgyzstan)] [Kyrgyz-Russian Slavic University (Kyrgyzstan)

    2013-07-15T23:59:59.000Z

    The characteristics of a microwave discharge in an argon jet injected axially into a coaxial channel with a shortened inner electrode are numerically analyzed using a self-consistent equilibrium gas-dynamic model. The specific features of the excitation and maintenance of the microwave discharge are determined, and the dependences of the discharge characteristics on the supplied electromagnetic power and gas flow rate are obtained. The calculated results are compared with experimental data.

  12. Industrial applications of variable frequency microwave energy in materials processing

    SciTech Connect (OSTI)

    Fathi, Z.; Tucker, D.A.; Lewis, W.A.; Wei, J.B. [Lambda Technologies, Inc., Raleigh, NC (United States)

    1996-12-31T23:59:59.000Z

    A review of some market-driven research, process applications and systems development is provided. The variable frequency microwave processing concepts are briefly described. Industrial processing using variable frequency microwave energy in the areas of polymerization, composite processing, bonding and plasma is discussed. Analytical applications inherent in the use of variable frequency and its control are demonstrated in the areas of materials signature analysis for volumetric cure monitoring.

  13. Proposal for an Optomechanical Microwave Sensor at the Subphoton Level

    E-Print Network [OSTI]

    Keye Zhang; Francesco Bariani; Ying Dong; Weiping Zhang; Pierre Meystre

    2015-03-17T23:59:59.000Z

    Because of their low energy content, microwave signals at the single-photon level are extremely challenging to measure. Guided by recent progress in single-photon optomechanics and hybrid optomechanical systems, we propose a multimode optomechanical transducer that can detect intensities significantly below the single-photon level via adiabatic transfer of the microwave signal to the optical frequency domain where the measurement is then performed. The influence of intrinsic quantum and thermal fluctuations is also discussed.

  14. Microwave mode shifting antenna system for regenerating particulate filters

    DOE Patents [OSTI]

    Gonze, Eugene V [Pinckney, MI; Kirby, Kevin W [Calabasas Hills, CA; Phelps, Amanda [Malibu, CA; Gregoire, Daniel J [Thousand Oaks, CA

    2011-04-26T23:59:59.000Z

    A regeneration system comprises a particulate matter (PM) filter including a microwave energy absorbing surface, and an antenna system comprising N antennas and an antenna driver module that sequentially drives the antenna system in a plurality of transverse modes of the antenna system to heat selected portions of the microwave absorbing surface to regenerate the PM filter, where N is an integer greater than one. The transverse modes may include transverse electric (TE) and/or transverse magnetic (TM) modes.

  15. Mathematical and experimental modelling of heat pump assisted microwave drying

    SciTech Connect (OSTI)

    Xiguo Jia (Univ. of Queensland (Australia))

    1993-01-01T23:59:59.000Z

    Drying is one of the most energy intensive operations in industry and agriculture. In the quest to increase drying efficiency and product quality, new technologies and methods are constantly being sought. Of these technologies, heat pump assisted drying and microwave drying have proved to be the most promising contenders. In order to achieve a better understanding and provide a computer design tool for heat pump assisted convective and microwave drying, both mathematical modelling and experimental investigations of heat pump assisted microwave dryers have been undertaken in this study. A mathematical model has been developed to predict the steady-state performance of a heat pump assisted continuous microwave dryer, with emphasis on the simulation of heat and mass transfer processes in the evaporator and drying chamber. The model is intend to serve as a design tool in the study of heat pump dryers. To achieve the optimum design, the influences of the key design and operating parameters, as well as the comparison of different drying configurations, have been examined. Based on investigation results, several methods have been proposed to improve the performance of heat pump assisted microwave drying, such as the use of a recuperator. To validate the above mathematical model, extensive drying tests using foam rubber as the test material have been conducted on a prototype heat pump assisted microwave dryer. The prototype heat pump input power was 5 kW with a maximum microwave input power of 10 kW. The experimental performance data confirmed the veracity of the simulation model. The experimental results on drying test materials indicate that with careful design heat pump assisted microwave drying is comparable to convective drying in energy consumption while with a much higher drying speed.

  16. Microwaves and Chemistry: The Catalysis of an Exciting Marriage

    E-Print Network [OSTI]

    Wan, J.

    been the bias of chemists, raised on the principles of quantum mechanics, who concluded that the energy provided by microwave radiation was too low to cause bond breaking or electron transfer reactions. In the past ten years we have adapted a... surfaces, the peak power and the duration of the microwave pulses, and the thermal conductivity of the catalyst. For each chemicaL system there exists a unique activation energy barrier for the forward reaction to proceed. A corresponding activation...

  17. Radio Frequency and Microwave Hazards Radio frequency (rf) and microwaves occur within the range 10 kHz to 300,000 MHz and are

    E-Print Network [OSTI]

    Shull, Kenneth R.

    kHz to 300,000 MHz and are used in rf ovens and furnaces, induction heaters, and microwave ovens. Microwave ovens are increasingly being used in laboratories for organic synthesis and digestion of analytical samples. Only microwave ovens designed for laboratory or industrial use should be used

  18. A SEARCH FOR 95 GHz CLASS I METHANOL MASERS IN MOLECULAR OUTFLOWS

    SciTech Connect (OSTI)

    Gan, Cong-Gui; Chen, Xi; Shen, Zhi-Qiang [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan RD, Shanghai 200030 (China)] [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan RD, Shanghai 200030 (China); Xu, Ye; Ju, Bing-Gang, E-mail: cggan@shao.ac.cn [Key Laboratory of Radio Astronomy, Chinese Academy of Sciences (China)] [Key Laboratory of Radio Astronomy, Chinese Academy of Sciences (China)

    2013-01-20T23:59:59.000Z

    We have observed a sample of 288 molecular outflow sources including 123 high-mass and 165 low-mass sources in order to search for class I methanol masers at the 95 GHz transition and to investigate the relationship between outflow characteristics and class I methanol maser emission with the Purple Mountain Observatory 13.7 m radio telescope. Our survey detected 62 sources with 95 GHz methanol masers above a 3{sigma} detection limit, which includes 47 high-mass sources and 15 low-mass sources. Therefore, the detection rate is 38% for high-mass outflow sources and 9% for low-mass outflow sources, suggesting that class I methanol masers are relatively easily excited in high-mass sources. There are 37 newly detected 95 GHz methanol masers (including 27 high-mass and 10 low-mass sources), 19 of which are newly identified (i.e., first identification) class I methanol masers (including 13 high-mass and 6 low-mass sources). A statistical analysis of the distributions of maser detections with the outflow parameters reveals that the maser detection efficiency increases with the outflow properties (e.g., mass, momentum, kinetic energy, mechanical luminosity of outflows, etc.). Systematic investigations of the relationships between the intrinsic luminosity of methanol masers and the outflow properties (including mass, momentum, kinetic energy, bolometric luminosity, and mass-loss rate of the central stellar sources) indicate a positive correlation. This further supports the theory that class I methanol masers are collisionally pumped and associated with shocks when outflows interact with the surrounding ambient medium.

  19. 86, 43, and 22 GHz VLBI Observations of 3C120

    E-Print Network [OSTI]

    Jose-Luis Gomez; Alan P. Marscher; Antonio Alberdi

    1999-06-11T23:59:59.000Z

    We present the first 86 GHz VLBI observations of the radio galaxy 3C~120, together with contemporaneous 43 and 22 GHz polarimetric VLBA observations. The very high angular resolution obtained at 86 GHz provides an upper limit to the size of the core of 54 $\\mu$as (0.025 $h^{-1}$pc). This represents a direct determination of the base of the jet which is independent of variability arguments (which depend on uncertain estimates of the Doppler factor), and places it below approximately one light-month. Comparison with previous VLBA observations after a one-year interval shows pronounced changes in the structure and polarization of the jet. Most of the components are found to follow a curved path while undergoing a steepening of their spectra accompanied by a decrease in total and polarized emission. However, at least one component is observed to follow a quasi-ballistic motion, accompanied by a flattening of its spectrum, as well as an increase in total and polarized flux. This may be explained by its interaction with the external medium, resulting in a shock that enhances the emission and aligns the magnetic field perpendicular to the component motion, thereby producing an increase of the degree of polarization from undetected values to as high as 15%. A second strong component, with the highest degree of polarization (23%), is found to have experienced a displacement from the ridge line of the structural position angle of the jet as it moved downstream. We have found a mean swing to the south of the position angle of the innermost components of $\\sim 6^{\\circ}$ between late 1996 and 1997, which may be responsible for the jet curvature observed at parsec and kiloparsec scales.

  20. Radio Frequency Surface Impedance Characterization System for Superconducting Samples at 7.5 GHz

    SciTech Connect (OSTI)

    Binping Xiao, Charles Reece, Michael Kelley, Larry Phillips, Rongli Geng, Haipeng Wang, Frank Marhauser

    2011-05-01T23:59:59.000Z

    A radio frequency (RF) surface impedance characterization (SIC) system that uses a sapphire-loaded Nb cavity operating at 7.5 GHz has been fabricated to measure the RF surface impedance of flat superconducting samples. Currently, the SIC system can make direct calorimetric surface impedance measurements in the central 0.8 cm2 area of 5 cm diameter disk samples in a temperature range from 2 to 20 K, exposed to a magnetic flux density of up to 14 mT. As an application, we present the measurement results for a bulk Nb sample.

  1. Ring shaped 6.7 GHz methanol maser emission around a young high-mass star

    E-Print Network [OSTI]

    A. Bartkiewicz; M. Szymczak; H. J. van Langevelde

    2005-09-21T23:59:59.000Z

    We report on EVN imaging of the 6.7 GHz methanol maser emission from the candidate high-mass protostar G23.657-0.127. The masers originate in a nearly circular ring of 127 mas radius and 12 mas width. The ring structure points at a central exciting object which characteristics are typical for a young massive star; its bolometric luminosity is estimated to be methanol masers originate in a spherical bubble or in a rotating disc seen nearly face-on.

  2. High power tests of dressed supconducting 1.3 GHz RF cavities

    SciTech Connect (OSTI)

    Hocker, A.; Harms, E.R.; Lunin, A.; Sukhanov, A.; /Fermilab

    2011-03-01T23:59:59.000Z

    A single-cavity test cryostat is used to conduct pulsed high power RF tests of superconducting 1.3 GHz RF cavities at 2 K. The cavities under test are welded inside individual helium vessels and are outfitted ('dressed') with a fundamental power coupler, higher-order mode couplers, magnetic shielding, a blade tuner, and piezoelectric tuners. The cavity performance is evaluated in terms of accelerating gradient, unloaded quality factor, and field emission, and the functionality of the auxiliary components is verified. Test results from the first set of dressed cavities are presented here.

  3. Vertical and horizontal test results of 3.9-GHz accelerating cavities at FNAL

    SciTech Connect (OSTI)

    Khabiboulline, T.; Edwards, H.; Foley, M.; Harms, E.; Hocker, James Andrew; Mitchell, D.; Rowe, A.; Solyak, N.; /Fermilab

    2008-06-01T23:59:59.000Z

    The 3rd harmonic 3.9GHz accelerating cavity was proposed to improve the beam performance of the VUV FEL, FLASH. In the frame of a collaborative agreement, Fermilab will provide DESY with a cryomodule containing a string of four cavities. Seven 9-cell Nb cavities were tested and six of them did reach accelerating gradient up to 24 MV/m almost twice more than design value of 14 MV/m. Two of these cavities are with new HOM couplers with improved design. In this paper we present all results of the vertical and horizontal tests.

  4. Uniform bulk material processing using multimode microwave radiation

    DOE Patents [OSTI]

    Varma, Ravi (Los Alamos, NM); Vaughn, Worth E. (Madison, WI)

    2000-01-01T23:59:59.000Z

    An apparatus for generating uniform heating in material contained in a cylindrical vessel is described. TE.sub.10 -mode microwave radiation is coupled into a cylindrical microwave transition such that microwave radiation having TE.sub.11 -, TE.sub.01 - and TM.sub.01 -cylindrical modes is excited therein. By adjusting the intensities of these modes, substantially uniform heating of materials contained in a cylindrical drum which is coupled to the microwave transition through a rotatable choke can be achieved. The use of a poor microwave absorbing insulating cylindrical insert, such as aluminum oxide, for separating the material in the container from the container walls and for providing a volume through which air is circulated is expected to maintain the container walls at room temperature. The use of layer of highly microwave absorbing material, such as SiC, inside of the insulating insert and facing the material to be heated is calculated to improve the heating pattern of the present apparatus.

  5. Microwave processing of ceramic oxide filaments. Annual report, FY1997

    SciTech Connect (OSTI)

    Vogt, G.J.

    1998-12-31T23:59:59.000Z

    The objective of the microwave filament processing project is to develop microwave techniques to manufacture continuous ceramic oxide filaments. Microwave processing uses the volumetric absorption of microwave power in oxide filament tows to drive off process solvents, to burn out organic binders, and to sinter the dried fibers to produce flexible, high-strength ceramic filaments. The technical goal is to advance filament processing technology by microwave heating more rapidly with less energy and at a lower cost than conventional processing, but with the same quality as conventional processing. The manufacturing goal is to collaborate with the 3M Company, a US manufacturer of ceramic oxide filaments, to evaluate the technology using a prototype filament system and to transfer the microwave technology to the 3M Company. Continuous ceramic filaments are a principal component in many advanced high temperature materials like continuous fiber ceramic composites (CFCC) and woven ceramic textiles. The use of continuous ceramic filaments in CFCC radiant burners, gas turbines, waste incineration, and hot gas filters in U.S. industry and power generation is estimated to save at least 2.16 quad/yr by year 2010 with energy cost savings of at least $8.1 billion. By year 2010, continuous ceramic filaments and CFCC`s have the potential to abate pollution emissions by 917,000 tons annually of nitrous oxide and 118 million tons annually of carbon dioxide (DOE Report OR-2002, February, 1994).

  6. Development and research of a coaxial microwave plasma thruster

    SciTech Connect (OSTI)

    Yang Juan; Xu Yingqiao; Tang Jinlan; Mao Genwang; Yang Tielian [College of Astronautics, Northwestern Polytechnic University, Xi'an 710072 (China); Tan Xiaoquen [School of Mechatronics, Northwestern Polytechnic University, Xi'an 710072 (China)

    2008-08-15T23:59:59.000Z

    An overview of the research on a coaxial microwave plasma thruster at Northwestern Polytechnic University is presented. Emphasis is put on the development and research on key components of the thruster system, a microthrust balance, plasma plume diagnostics, and a numerical simulation of the plasma flow field inside the thruster cavity. The developed thruster cavity is chosen from a coaxial resonant cavity with concentrated capacitance, which can operate well in atmosphere and vacuum conditions. The development of a microwave source shows that a magnetron powered by a switch power supply has advantages in the power level and efficiency, but a solid state microwave source synthesized from the arsenide field effect transistor is superior in weight and volume. Through elimination of the effect of large gravity and resistance force induced by a gas pipe line and a microwave transmitting line on the microthrust, 15 mN and 340 s in the performance of the microwave plasma thruster at 70 W and with helium gas are measured. Diagnosing experiment shows that the plasma plume density is in the range of (1-7.2)x10{sup 16}/m{sup 3}. Numerical simulation of the plasma flow field inside the coaxial thruster cavity shows that there is a good match between the microwave power and gas flow rate.

  7. 1014 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 52, NO. 3, MARCH 2004 Recycling Ambient Microwave Energy With

    E-Print Network [OSTI]

    1014 IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 52, NO. 3, MARCH 2004 Recycling are in wireless powering of industrial sensors and recycling of ambient RF energy. A 64-el- ement dual

  8. Investigating the effective range of vacuum ultraviolet-mediated breakdown in high-power microwave metamaterials

    SciTech Connect (OSTI)

    Liu, Chien-Hao, E-mail: cliu82@wisc.edu; Neher, Joel D., E-mail: jdneher@wisc.edu; Booske, John H., E-mail: booske@engr.wisc.edu; Behdad, Nader, E-mail: behdad@wisc.edu [Department of Electrical and Computer Engineering, University of Wisconsin-Madison, 1415 Engineering Drive, Madison, Wisconsin 53706 (United States)

    2014-10-14T23:59:59.000Z

    Metamaterials and periodic structures operating under high-power excitations are susceptible to breakdown. It was recently demonstrated that a localized breakdown created in a given region of a periodic structure can facilitate breakdown in other regions of the structure where the intensity of the incident electromagnetic fields may not be high enough to cause breakdown under normal circumstances. It was also demonstrated that this phenomenon is due to the generation of vacuum ultraviolet radiation at the location of the initial discharge, which propagates to the neighboring regions (e.g., other unit cells in a periodic structure) and facilitates the generation of a discharge at a lower incident power level. In this paper, we present the results of an experimental study conducted to determine the effective range of this physical phenomenon for periodic structures that operate in air and in pure nitrogen gas at atmospheric pressure levels. It is demonstrated that when breakdown is induced in a periodic structure using a high-power pulse with a frequency of 9.382 GHz, duration of 0.8 ?s, and peak power level of 25 kW, this phenomenon is highly likely to happen in radii of approximately 16–17 mm from the location of the initial discharge under these test conditions. The results of this study are significant in designing metamaterials and periodic structures for high-power microwave applications as they suggest that a localized discharge created in such a periodic structure with a periodicity less than 16–17 mm can spread over a large surface and result in a distributed discharge.

  9. Phenomenological method of calculating microwave longitudinal coupling impedances

    SciTech Connect (OSTI)

    Giordano, S.; Votruba, J.

    1980-05-01T23:59:59.000Z

    A previous paper described an investigation of the longitudinal coupling impedance of the TM/sub olm/ modes in the ISA vacuum chamber. A method was developed for calculating these impedances by using the data derived from pertubation measurements. This method gave accurate results between 2.6 and 2.8 GHz, but above 2.8 GHz measurements became difficult because of the mixing of the TM/sub olm/ modes with other modes. This paper presents a phenomenological approach for calculating these impedances based on previously developed concepts.

  10. First Season QUIET Observations: Measurements of CMB Polarization Power Spectra at 43 GHz in the Multipole Range 25 <= ell <= 475

    E-Print Network [OSTI]

    Bischoff, C; Buder, I; Chinone, Y; Cleary, K; Dumoulin, R N; Kusaka, A; Monsalve, R; Næss, S K; Newburgh, L B; Reeves, R; Smith, K M; Wehus, I K; Zuntz, J A; Zwart, J T L; Bronfman, L; Bustos, R; Church, S E; Dickinson, C; Eriksen, H K; Ferreira, P G; Gaier, T; Gundersen, J O; Hasegawa, M; Hazumi, M; Huffenberger, K M; Jones, M E; Kangaslahti, P; Kapner, D J; Lawrence, C R; Limon, M; May, J; McMahon, J J; Miller, A D; Nguyen, H; Nixon, G W; Pearson, T J; Piccirillo, L; Radford, S J E; Readhead, A C S; Richards, J L; Samtleben, D; Seiffert, M; Shepherd, M C; Staggs, S T; Tajima, O; Thompson, K L; Vanderlinde, K; Williamson, R; Winstein, B

    2010-01-01T23:59:59.000Z

    The Q/U Imaging ExperimenT (QUIET) employs coherent receivers at 43GHz and 95GHz, operating on the Chajnantor plateau in the Atacama Desert in Chile, to measure the anisotropy in the polarization of the CMB. QUIET primarily targets the B modes from primordial gravitational waves. The combination of these frequencies gives sensitivity to foreground contributions from diffuse Galactic synchrotron radiation. Between 2008 October and 2010 December, >10,000hours of data were collected, first with the 19-element 43GHz array (3458hours) and then with the 90-element 95GHz array. Each array observes the same four fields, selected for low foregrounds, together covering ~1000deg^2. This paper reports initial results from the 43GHz receiver which has an array sensitivity to CMB fluctuations of 69uK sqrt(s). The data were extensively studied with a large suite of null tests before the power spectra, determined with two independent pipelines, were examined. Analysis choices, including data selection, were modified until th...

  11. A 77 GHz Transceiver for Automotive Radar System Using a120nm In AlAs/In GaAs Metamorphic HEMTs

    E-Print Network [OSTI]

    Kwon, Youngwoo

    A 77 GHz Transceiver for Automotive Radar System Using a120nm 0.4 0.35 In AlAs/In GaAs Metamorphic-mail:ykwon@snu.ac.kr) Abstract -- In this work, we demonstrate a compact 77GHz single-chip transceiver for an automotive radar at the transmitter and a 5dB conversion gain at the receiver. Index Terms -- Automotive radar, 77GHz, MHEMT, MMIC

  12. The 110 GHz ECH installation on DII-D: Status and initial experimental results

    SciTech Connect (OSTI)

    Lohr, J.; Callis, R.W.; O`Neill, R.C. [Univ. of Texas, Austin, TX (United States)] [and others

    1997-05-01T23:59:59.000Z

    Two 110 GHz gyrotrons with nominal output power of 1 MW each have been installed on the DIII-D tokamak. The gyrotrons, produced by Gycom and Communications and Power Industries, are connected to the tokamak by windowless evacuated transmission lines using circular corrugated waveguide carrying the HE{sub 11} mode. Initial experiments with the Gycom gyrotron showed good central heating efficiency at the second harmonic resonance with record central electron temperatures for DIII-D in excess of 10 keV achieved. The beam spot in the DIII-D vacuum vessel was well focused, with a diameter of approximately 8 cm, and it could be steered poloidally by a remotely adjustable mirror. The injection was at 19 deg off-perpendicular for current drive and the beams could be modulated for studies of energy transport and power deposition. The system will be described and the initial physics results will be presented. A third gyrotron, also at 110 GHz, will be installed later this year. Progress with this CPI tube will be discussed and future plans for the ECH installation and physics experiments using it will be presented.

  13. A Megawatt-level 28z GHz Heating System For The National Spherical Torus Experiment Upgrade

    SciTech Connect (OSTI)

    Taylor, Gary

    2014-04-01T23:59:59.000Z

    The National Spherical Torus Experiment Upgrade (NSTX-U) will operate at axial toroidal fields of < 1 T and plasma currents, Ip < 2 MA. The development of non-inductive (NI) plasmas is a major long-term research goal for NSTX-U. Time dependent numerical simulations of 28 GHz electron cyclotron (EC) heating of low density NI start-up plasmas generated by Coaxial Helicity Injection (CHI) in NSTX-U predict a significant and rapid increase of the central electron temperature (Te(0)) before the plasma becomes overdense. The increased Te(0) will significantly reduce the Ip decay rate of CHI plasmas, allowing the coupling of fast wave heating and neutral beam injection. A megawatt-level, 28 GHz electron heating system is planned for heating NI start-up plasmas in NSTX-U. In addition to EC heating of CHI start-up discharges, this system will be used for electron Bernstein wave (EBW) plasma start-up, and eventually for EBW heating and current drive during the Ip flattop.

  14. 6.7GHz Methanol Maser Associated Outflows: An evolutionary sequence

    E-Print Network [OSTI]

    de Villiers, H M; Thompson, M A; Urquhart, J S; Breen, S L; Burton, M G; Ellingsen, S P; Fuller, G A; Pestalozzi, M; Voronkov, M A; Ward-Thompson, D

    2015-01-01T23:59:59.000Z

    We present a continuing study of a sample 44 molecular outflows, observed in 13CO lines, closely associated with 6.7GHz methanol masers, hence called Methanol Maser Associated Outflows (MMAOs). We compare MMAO properties with those of outflows from other surveys in the literature. In general, MMAOs follow similar trends, but show a deficit in number at low masses and momenta, with a corresponding higher fraction at the high end of the distributions. A similar trend is seen for the dynamical timescales of MMAOs. We argue that the lack of relatively low mass and young flows in MMAOs is due to the inherent selection-bias in the sample, i.e. its direct association with 6.7GHz methanol masers. This implies that methanol masers must switch on after the onset of outflows (hence accretion), and not before a sufficient abundance of methanol is liberated from icy dust mantles. Consequently the average dynamical age of MMAOs is older than for the general population of molecular outflows. We propose an adjusted evolution...

  15. Development of a high-temperature oven for the 28 GHz electron cyclotron resonance ion source

    SciTech Connect (OSTI)

    Ohnishi, J., E-mail: ohnishi@riken.jp; Higurashi, Y.; Kidera, M.; Ozeki, K.; Nakagawa, T. [RIKEN Nishina Center, Wako, Saitama 351-0198 (Japan)] [RIKEN Nishina Center, Wako, Saitama 351-0198 (Japan)

    2014-02-15T23:59:59.000Z

    We have been developing the 28 GHz ECR ion source in order to accelerate high-intensity uranium beams at the RIKEN RI-beam Factory. Although we have generated U{sup 35+} beams by the sputtering method thus far, we began developing a high-temperature oven with the aim of increasing and stabilizing the beams. Because the oven method uses UO{sub 2}, a crucible must be heated to a temperature higher than 2000?°C to supply an appropriate amount of UO{sub 2} vapor to the ECR plasma. Our high-temperature oven uses a tungsten crucible joule-heated with DC current of approximately 450 A. Its inside dimensions are ?11 mm × 13.5 mm. Since the crucible is placed in a magnetic field of approximately 3 T, it is subject to a magnetic force of approximately 40 N. Therefore, we used ANSYS to carefully design the crucible, which was manufactured by machining a tungsten rod. We could raise the oven up to 1900?°C in the first off-line test. Subsequently, UO{sub 2} was loaded into the crucible, and the oven was installed in the 28 GHz ECR ion source and was tested. As a result, a U{sup 35+} beam current of 150 ?A was extracted successfully at a RF power of approximately 3 kW.

  16. Microwave processing of Tantalum capacitors. CRADA final report

    SciTech Connect (OSTI)

    McMillan, A.D.; Lauf, R.J.; Vierow, W.F.

    1998-03-01T23:59:59.000Z

    A Cooperative Research and Development Agreement (CRADA) between Lockheed Martin Energy Systems, Inc. (LMES) and AVX Tantalum Corporation (AVX) of Biddeford, Maine, was initiated in October 1991. [Lockheed Martin Energy Research Corp. (LMER) has replaced LMES]. The completion date for the Agreement was March 1996. The purpose of this work is to explore the feasibility of an advanced microwave processing concept to develop higher capacitance tantalum anodes. Tantalum capacitors are used where high reliability is needed (e.g., pacemakers, hearing aids, and military devices). Two types of tantalum powder are used: sodium-reduced powder and electron beam-refined powder. Sodium-reduced powder has higher surface area, but lower purity; electron beam-refined powder has higher purity for working voltages, but somewhat lower surface area. The powder is pressed into pellets using traditional methods and then placed in the microwave furnace for processing. It is of interest to determine if variable-frequency microwave sintering can increase quality while decreasing processing time and decreasing or eliminating surface contamination; these issues must be addressed while retaining the maximum surface area of the anode. Meeting each of these needs will result in a higher quality anodic film, which will thereby increase the dielectric strength. Additionally, microwave sintering might enable the authors to develop a strong sintered anode without excessive grain growth. The variable-frequency microwave furnace (VFMF), located at the Y-12 Plant, allows the authors to study the effects of sintering over a wide frequency range. This novel design uses a high-power traveling wave tube (TWT), originally developed for electronic warfare. By using this microwave source, one can not only select individual microwave frequencies for particular experiments, but also achieve uniform power densities over a large area by the superposition of many different frequencies.

  17. Detection of lower hybrid waves in the scrape-off layer of tokamak plasmas with microwave backscattering

    SciTech Connect (OSTI)

    Baek, S. G., E-mail: sgbaek@mit.edu; Shiraiwa, S.; Parker, R. R.; Bonoli, P. T.; Marmar, E. S.; Wallace, G. M.; Lau, C. [MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States)] [MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States); Dominguez, A.; Kramer, G. J. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)] [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

    2014-01-15T23:59:59.000Z

    Microwave backscattering experiments have been performed on the Alcator C-Mod tokamak in order to investigate the propagation of lower hybrid (LH) waves in reactor-relevant, high-density plasmas. When the line-averaged density is raised above 1?×?10{sup 20} m{sup –3}, lower hybrid current drive efficiency is found to be lower than expected [Wallace et al., Phys. Plasmas 19, 062505 (2012)] and LH power is thought to be dissipated at the plasma edge. Using a single channel (60 GHz) ordinary-mode (O-mode) reflectometer system, we demonstrate radially localized LH wave measurements in the scrape-off layer of high density plasmas (n{sup ¯}{sub e}???0.9×10{sup 20}?m{sup ?3}). Measured backscattered O-mode power varies depending on the magnetic field line mapping, suggesting the resonance cone propagation of LH waves. Backscattered power is also sensitive to variations in plasma density and the launched parallel refractive index of the LH waves. LH ray-tracing simulations have been carried out to interpret the observed variations. To understand the measured LH waves in regions not magnetically connected to the launcher, two hypotheses are examined. One is the weak single pass absorption and the other is scattering of LH waves by non-linear effects.

  18. High quality Y-type hexaferrite thick films for microwave applications by an economical and environmentally benign crystal growth technique

    SciTech Connect (OSTI)

    Hu, Bolin; Chen, Yajie, E-mail: y.chen@neu.edu; Gillette, Scott; Su, Zhijuan; Harris, Vincent G. [Center for Microwave Magnetic Materials and Integrated Circuits and Department of Electrical and Computer Engineering, Northeastern University, Boston, Massachusetts 02115 (United States); Wolf, Jason; McHenry, Michael E. [Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States)

    2014-02-17T23:59:59.000Z

    Thick barium hexaferrite Ba{sub 2}Zn{sub 2}Fe{sub 12}O{sub 22} (i.e., Zn{sub 2}Y) films having thicknesses of ?100??m were epitaxially grown on MgO (111) substrates using an environmentally benign ferrite-salt mixture by vaporizing the salt. X-ray diffraction pole figure analyses showed (00l) crystallographic alignment with little in plane dispersion confirming epitaxial growth. Saturation magnetization, 4?M{sub s}, was measured for as-grown films to be 2.51?±?0.1?kG with an out of plane magnetic anisotropy field H{sub A} of 8.9?±?0.1?kOe. Ferromagnetic resonance linewidth, as the peak-to-peak power absorption derivative at 9.6?GHz, was measured to be 62?Oe. These properties demonstrate a rapid, convenient, cost-effective, and nontoxic method of growing high quality thick crystalline ferrite films which could be used widely for microwave device applications.

  19. Physical principles of microwave assisted magnetic recording

    SciTech Connect (OSTI)

    Rivkin, Kirill; Benakli, Mourad; Yin, Huaqing [Seagate Technology, Edina, Minnesota 55435 (United States); Tabat, Ned [Semaphore Scientific Inc., Chanhassen, Minnesota 55317 (United States)

    2014-06-07T23:59:59.000Z

    While the basic physics of Microwave Assisted Magnetization Reversal (MAMR) phenomenon is well established both theoretically and experimentally, its application in a practical magnetic recording environment was so far studied primarily with the help of micromagnetic recording models. In this work, we instead attempt to use analytical formulation and simple numerical models to understand the main challenges as well as benefits that are associated with such a system. It appears that the main difference between the previously introduced theory [G. Bertotti et al., Phys. Rev. Lett. 86, 724 (2001); K. Rivkin et al., Appl. Phys. Lett. 92, 153104 (2008); S. Okamoto et al., J. Appl. Phys. 107, 123914 (2010).] and recording environment is that both the RF and DC magnetic fields are applied at a substantial angle to the anisotropy axis. While the associated symmetry breaking prevents one from describing the reversal process explicitly, it is possible to approximate the solutions well enough to satisfactorily match numerical models both in the case of wire and Spin Torque Oscillator generated RF fields. This approach allows for physical explanation of various effects associated with MAMR such as high gradient of writeable anisotropy and reduction of track width, and offers a clear guidance regarding future optimization of MAMR recording.

  20. Characterization of melter slurries vitrified by microwave

    SciTech Connect (OSTI)

    Jantzen, C.M.

    1991-04-01T23:59:59.000Z

    Liquid high-level nuclear waste will be immobilized at the Savannah River Site (SRS) by vitrification in borosilicate glass in the Defense Waste Processing Facility (DWPF). In this facility, control of the oxidation/reduction (redox) equilibrium in the glass melter is critical for processing of the nuclear waste. As part of the DWPF process control strategy, the glass redox expected in the melter will be determined by measuring the ratio of ferrous to ferric ions in vitrified slurry from the slurry mix evaporator (SME). Chemical analysis of this vitrified feed will also be used for other process control constraints which are related to glass viscosity, liquidus, and waste component solubility. In addition, the canisters of borosilicate waste glass produced in the DWPF must comply with the Waste Acceptance Preliminary Specifications (WAPS) established by the DOE Office of Civilian Radioactive Waste Management. Specification 1.1.2 requires that the elemental composition of the glass be reported. The elemental analyses will be performed on vitrified melter feed taken from the melter feed tank (MFT). Conventional vitrification of SME/MFT slurries takes 4 hours at the DWPF melt temperature of 1150{degrees}C. Microwave vitrification of melter feed slurries has been shown to significantly reduce the time required to vitrify slurry samples.

  1. Cosmic Microwave Background Anisotropy Window Functions Revisited

    E-Print Network [OSTI]

    Lloyd Knox

    1999-09-28T23:59:59.000Z

    The primary results of most observations of cosmic microwave background (CMB) anisotropy are estimates of the angular power spectrum averaged through some broad band, called band-powers. These estimates are in turn what are used to produce constraints on cosmological parameters due to all CMB observations. Essential to this estimation of cosmological parameters is the calculation of the expected band-power for a given experiment, given a theoretical power spectrum. Here we derive the "band power" window function which should be used for this calculation, and point out that it is not equivalent to the window function used to calculate the variance. This important distinction has been absent from much of the literature: the variance window function is often used as the band-power window function. We discuss the validity of this assumed equivalence, the role of window functions for experiments that constrain the power in {\\it multiple} bands, and summarize a prescription for reporting experimental results. The analysis methods detailed here are applied in a companion paper to three years of data from the Medium Scale Anisotropy Measurement.

  2. Microwave Tokamak Experiment (MTX) ohmic heating system

    SciTech Connect (OSTI)

    Jackson, M.C. (Lawrence Livermore National Lab., CA (USA))

    1989-09-13T23:59:59.000Z

    The ohmic heating system for the Microwave Tokamak Experiment (MTX) at Lawrence Livermore National Laboratory (LLNL) provides both the voltage for the initial breakdown phase and the energy to drive the plasma current to a value of 400 kA or greater. Providing this voltage and flux swing requires a one-turn loop voltage of about 25 volts (11 kV across the coil) and a magnetic flux swing of 2 volt- seconds. This voltage and flux swing are accomplished by charging the ohmic heating coils to 20 kA, at which point the current is commutated off into a resistor generating the 11 kV across the coil. When the current passes through zero, another power supply drives the current in the opposite polarity to 20 kA, thus completing the full 2 volt-second flux swing. This paper describes the design features and performance of the ohmic heating circuit, with emphasis on the commutation circuit. In addition, the paper describes the use of the ohmic heating system for discharge cleaning and the changeover procedure. 3 refs., 4 figs., 1 tab.

  3. 86 GHz Very Long Baseline Polarimetry of 3C273 and 3C279 with the Coordinated Millimeter VLBI Array

    E-Print Network [OSTI]

    Joanne M. Attridge

    2001-04-18T23:59:59.000Z

    86 GHz Very Long Baseline Polarimetry probes magnetic field structures within the cores of Active Galactic Nuclei at higher angular resolutions and a spectral octave higher than previously achievable. Observations of 3C273 and 3C279 taken in April 2000 with the Coordinated Millimeter VLBI Array have resulted in the first total intensity (Stokes I) and linear polarization VLBI images reported of any source at 86 GHz. These results reveal the 86 GHz electric vector position angles within the jets of 3C273 and 3C279 to be orthogonal to each other, and the core of 3C273 to be unpolarized. If this lack of polarization is due to Faraday depolarization alone, the dispersion in rotation measure is >=90000 rad/m^2 for the core of 3C273.

  4. Direct modulation and active mode locking of ultrahigh speed GaAlAs lasers at frequencies up to 18 GHz

    SciTech Connect (OSTI)

    Lau, K.Y.; Yariv, A.

    1985-02-15T23:59:59.000Z

    It is demonstrated that an ultrahigh speed window buried heterostructure GaAlAs laser fabricated on a semi-insulating substrate can be used as a narrowband signal transmitter in the Ku band frequency range (12--20 GHz). The modulation efficiency can be increased over a limited bandwidth by a weak optical feedback. A stronger optical feedback enables one to actively mode lock the laser diode at a very high repetition rate up to 17.5 GHz, producing pulses approx.12 ps long.

  5. Ground-Based and Airborne (PMS 2-D Probe Canister-Mounted) 183 GHz Water

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.NewofGeothermal Heaton Armed ServicesGround-Based MicrowaveVapor

  6. Microwave Power Beaming Infrastructure for Manned Lightcraft Operations: Part 2

    SciTech Connect (OSTI)

    Myrabo, Leik N. [Lightcraft Technologies, Inc., Bennington, VT (United States)

    2008-04-28T23:59:59.000Z

    In the past {approx}7 years, microwave gyrotron technology has rapidly evolved to a critical threshold wherein ultra-energetic space launch missions based on beamed energy propulsion (BEP) now appear eminently feasible. Over the next 20 years, hundred megawatt-class microwave power-beaming stations could be prototyped on high deserts and 3- to 4 km mountain peaks before migrating into low Earth orbit, along with their passive microwave relay satellites. Described herein is a 20 GW rechargeable nuclear power satellite and microwave power-beaming infrastructure designed for manned space launch operations in the year 2025. The technological readiness of 2500 GJ superconducting magnetic energy storage 'batteries', 433-m ultralight space structures, 100 MW liquid droplet radiators, 1-6+ MW gyrotron sources, and mega-scale arrays (e.g., 3000 phase-locked units) is addressed. Microwave BEP is 'breakthrough' technology with the very real potential to radically reduce space access costs by factors of 100 to 1000 in the forseeable future.

  7. Techniques for Probing the Processes by Which Microwaves Interact with Chemical and Biological Systems 

    E-Print Network [OSTI]

    Kay, Philip E

    2007-01-01T23:59:59.000Z

    Microwave heating is a relatively mature field and is theoretically well understood. However, recently there has been debate as to whether microwaves can interact with chemical and biological systems by means other than ...

  8. Letter to the Editor Microwave assisted exfoliation and reduction of graphite

    E-Print Network [OSTI]

    Letter to the Editor Microwave assisted exfoliation and reduction of graphite oxide yet versatile method to simultaneously achieve the exfoliation and reduction of graphite oxide of crumpled, few-layer thick and electronically conductive graphitic sheets. Using the microwave exfoliated

  9. be virtually impossible to construct land lines and microwave networks in the

    E-Print Network [OSTI]

    Brewer, Eric A.

    ) with a microwave radio transmission tail is not suit- able for very harsh terrain, or for locations that are more. The use of microwave repeater towers, requiring line- of-sight from one tower to the next, was ruled out

  10. Microwave-assisted pyrolysis of HDPE using an activated carbon bed

    E-Print Network [OSTI]

    Russell, Alan Donald

    2013-04-16T23:59:59.000Z

    away” into a landfill after a single use. Microwave-assisted pyrolysis is a recycling technique that allows the recovery of chemical value from plastic waste by breaking down polymers into useful smaller hydrocarbons using microwave heat in the absence...

  11. Attosecond timing jitter modelocked lasers and ultralow phase noise photonic microwave oscillators

    E-Print Network [OSTI]

    Li, Duo, Ph. D. Massachusetts Institute of Technology

    2014-01-01T23:59:59.000Z

    Photonic microwave oscillator based on optical frequency comb and ultrastable optical reference cavity represents the state-of-the-art solution to generate X-band microwaves of ultralow phase noise. Such high-quality ...

  12. Sub-300 nm InGaAs/InP Type-I DHBTs with a 150 nm collector, 30 nm base demonstrating 755 GHz fmax and 416 GHz f

    E-Print Network [OSTI]

    Rodwell, Mark J. W.

    operate up to 20 mW/µm2 before self-heating is observed to affect the DC characteristics. Index Terms and 416 GHz f Zach Griffith, Erik Lind and Mark J.W. Rodwell Dept. of Electrical and Computer Engineering. If this associated dipole is too weak, the electric field will reverse across the grade prematurely and inhibit

  13. MAJOR STRUCTURES OF THE INNER GALAXY DELINEATED BY 6.7 GHz METHANOL MASERS

    SciTech Connect (OSTI)

    Green, J. A.; Caswell, J. L.; McClure-Griffiths, N. M.; Breen, S. L.; Voronkov, M. A. [CSIRO Astronomy and Space Science, Australia Telescope National Facility, P.O. Box 76, Epping, NSW 1710 (Australia); Avison, A.; Fuller, G. A.; Gray, M. D. [Jodrell Bank Centre for Astrophysics, Alan Turing Building, University of Manchester, Manchester, M13 9PL (United Kingdom); Burton, M. G. [School of Physics, University of New South Wales, Sydney, NSW 2052 (Australia); Ellingsen, S. P. [School of Mathematics and Physics, University of Tasmania, Private Bag 37, Hobart, TAS 7001 (Australia); Pestalozzi, M. [INAF/IFSI, via del Fosso del Cabaliere 100, I-00133 Roma (Italy); Thompson, M. A. [Centre for Astrophysics Research, Science and Technology Research Institute, University of Hertfordshire, College Lane, Hatfield, AL10 9AB (United Kingdom)

    2011-05-20T23:59:59.000Z

    We explore the longitude-velocity distribution of 6.7 GHz methanol masers in the context of the inner structure of our Galaxy. We analyze the correlation in velocities within this distribution and identify density enhancements indicating large-scale regions of enhanced star formation. These are interpreted as the starting points of the spiral arms and the interaction of the Galactic bar with the 3 kpc arms. The methanol masers support the presence of a long thin bar with a 45{sup 0} orientation. Signatures of the full 3 kpc arm structure are seen, including a prominent tangent at approximately -22{sup 0} Galactic longitude. We compare this distribution with existing models of the gas dynamics of our Galaxy. The 3 kpc arm structure appears likely to correspond to the radius of corotation resonance of the bar, with the bar on its inner surface and the starting points of the spiral arms on its outer surface.

  14. Concurrent 43 and 86 GHz Very Long Baseline Polarimetry of 3C273

    E-Print Network [OSTI]

    Joanne M. Attridge; John F. C. Wardle; Daniel C. Homan

    2005-06-10T23:59:59.000Z

    We present sub-milliarcsecond resolution total intensity and linear polarization VLBI images of 3C273, using concurrent 43 and 86 GHz data taken with the Very Long Baseline Array in May 2002. The structure seen in the innermost jet suggest that we have fortuitously caught the jet in the act of changing direction. The polarization images confirm that the core is unpolarized (fractional polarization m 5.2 x 10^{4} rad m^{-2} must be present in or in front of that region. These are among the highest rotation measures reported so far in the nucleus of any active galaxy or quasar, and must occur outside (but probably close to) the radio emitting region. The transverse rotation measure gradient is in the same sense as that observed by Asada et al and by Zavala and Taylor at greater core distances. The magnitude of the transverse gradient decreases rapidly with distance down the jet, and appears to be variable.

  15. A Search for 6.7 GHz Methanol Masers in M33

    E-Print Network [OSTI]

    P. F. Goldsmith; J. D. Pandian; A. A. Deshpande

    2007-10-09T23:59:59.000Z

    We report the negative results from a search for 6.7 GHz methanol masers in the nearby spiral galaxy M33. We observed 14 GMCs in the central 4 kpc of the Galaxy, and found 3 sigma upper limits to the flux density of ~9 mJy in spectral channels having a velocity width of 0.069 km/s. By velocity shifting and combining the spectra from the positions observed, we obtain an effective 3sigma upper limit on the average emission of ~1mJy in a 0.25 km/s channel. These limits lie significantly below what we would expect based on our estimates of the methanol maser luminosity function in the Milky Way. The most likely explanation for the absence of detectable methanol masers appears to be the metallicity of M33, which is modestly less than that of the Milky Way.

  16. 15 GHz Monitoring of the Gravitational Lens MG 0414+0534

    E-Print Network [OSTI]

    Christopher B. Moore; Jacqueline N. Hewitt

    1997-08-08T23:59:59.000Z

    We report the results of monitoring the four images of the gravitational lens MG 0414+0534 at 15 GHz. In 35 VLA maps spanning 180 days, we measure root-mean-square variations in the image light curves of ~3.5% mostly due to variations in the flux density calibration. The flux ratios, which are independent of flux density calibration variations, show root-mean-square variability of 1-3%. Extensive simulations of the data analysis process show that the observed variations in the flux ratios are likely to be due entirely to errors in the deconvolution process. It is possible that some of the observed variation is due to the source; however, the signal-to-noise ratio is too small to make a time delay determination using a data set of this size.

  17. A 2.45 GHz ECR ion source for production of medium charge states ions

    SciTech Connect (OSTI)

    Wutte, D.C.; Leitner, M.A.; Williams, M.D.; Leung, K.N.; Gough, R.A. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)] [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Saadatmand, K.; Benveniste, V. [Eaton Corporation, Beverly, Massachusetts 01915 (United States)] [Eaton Corporation, Beverly, Massachusetts 01915 (United States)

    1998-02-01T23:59:59.000Z

    At the Lawrence Berkeley National Laboratory we are constructing an ECR ion source test facility for nuclear science as well as industrial applications experiments. For these purposes, a single-stage 2.45 GHz electron cyclotron resonance ion source has been designed and constructed. It features an axial magnetic field with a mirror ratio of up to six and a hexapole field produced by a simple Nd{endash}Fe{endash}B permanent magnet assembly. In order to enhance the ion confinement time, the source plasma volume has been enlarged as much as possible while still maintaining a high mirror ratio. This paper describes the design of the ion source, the extraction system and the test stand. First, operational experience and experimental results with an argon discharge are presented. {copyright} {ital 1998 American Institute of Physics.}

  18. The generation of shared cryptographic keys through channel impulse response estimation at 60 GHz.

    SciTech Connect (OSTI)

    Young, Derek P.; Forman, Michael A.; Dowdle, Donald Ryan

    2010-09-01T23:59:59.000Z

    Methods to generate private keys based on wireless channel characteristics have been proposed as an alternative to standard key-management schemes. In this work, we discuss past work in the field and offer a generalized scheme for the generation of private keys using uncorrelated channels in multiple domains. Proposed cognitive enhancements measure channel characteristics, to dynamically change transmission and reception parameters as well as estimate private key randomness and expiration times. Finally, results are presented on the implementation of a system for the generation of private keys for cryptographic communications using channel impulse-response estimation at 60 GHz. The testbed is composed of commercial millimeter-wave VubIQ transceivers, laboratory equipment, and software implemented in MATLAB. Novel cognitive enhancements are demonstrated, using channel estimation to dynamically change system parameters and estimate cryptographic key strength. We show for a complex channel that secret key generation can be accomplished on the order of 100 kb/s.

  19. One piece microwave container screens for electrodeless lamps

    DOE Patents [OSTI]

    Turner, Brian (Myersville, MD); Ury, Michael (Bethesda, MD)

    1998-01-01T23:59:59.000Z

    A microwave powered electrodeless lamp includes an improved screen unit having mesh and solid sections with an internal reflector to reflect light into a light-transmitting chamber defined in the lamp microwave cavity by the reflector and the mesh section. A discharge envelope of a bulb is disposed in the light-transmitting chamber. Light emitted from the envelope is prevented by the reflector from entering the cavity portion bounded by the solid section of the screen. Replacing mesh material by solid metal material as part of the screen unit significantly reduces leakage of microwave energy from the lamp. The solid section has multiple compliant fingers defined therein for engaging the periphery of a flange on the waveguide unit so that a hose clamp can easily secure the screen to the assembly. Screen units of this type having different mesh section configurations can be interchanged in the lamp assembly to produce different respective illumination patterns.

  20. Optical emission spectroscopy of atmospheric pressure microwave plasmas

    SciTech Connect (OSTI)

    Jia Haijun; Fujiwara, Hiroyuki; Kondo, Michio [Research Center for Photovoltaics (RCPVs), National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan); Kuraseko, Hiroshi [Furukawa Electric Co., Ltd., Production Technology Development Center, 6 Yawata-Kaigandori, Chiba 290-8555 (Japan)

    2008-09-01T23:59:59.000Z

    The optical emission behaviors of Ar, He, and Ar+He plasmas generated in air using an atmospheric pressure microwave plasma source have been studied employing optical emission spectroscopy (OES). Emissions from various source gas species and air were observed. The variations in the intensities and intensity ratios of specific emissions as functions of the microwave power and gas flow rate were analyzed to investigate the relationship between the emission behavior and the plasma properties. We find that dependence of the emission behavior on the input microwave power is mainly determined by variations in electron density and electron temperature in the plasmas. On the other hand, under different gas flow rate conditions, changes in the density of the source gas atoms also significantly affect the emissions. Interestingly, when plasma is generated using an Ar+He mixture, emissions from excited He atoms disappear while a strong H{sub {alpha}} signal appears. The physics behind these behaviors is discussed in detail.

  1. Generation of circular polarization of the cosmic microwave background

    SciTech Connect (OSTI)

    Alexander, Stephon; Ochoa, Joseph; Kosowsky, Arthur [Department of Physics and Astronomy, Haverford College, Haverford, Pennsylvania 19041 (United States); Department of Physics, Institute for Gravitation and the Cosmos, Pennsylvania State University, 104 Davey Lab, University Park, Pennsylvania 16802 (United States); Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15208 (United States)

    2009-03-15T23:59:59.000Z

    The standard cosmological model, which includes only Compton scattering photon interactions at energy scales near recombination, results in zero primordial circular polarization of the cosmic microwave background. In this paper we consider a particular renormalizable and gauge-invariant standard model extension coupling photons to an external vector field via a Chern-Simons term, which arises as a radiative correction if gravitational torsion couples to fermions. We compute the transport equations for polarized photons from a Boltzmann-like equation, showing that such a coupling will source circular polarization of the microwave background. For the particular coupling considered here, the circular polarization effect is always negligible compared to the rotation of the linear polarization orientation, also derived using the same formalism. We note the possibility that limits on microwave background circular polarization may probe other photon interactions and related fundamental effects such as violations of Lorentz invariance.

  2. Microwave guiding in air along single femtosecond laser filament

    SciTech Connect (OSTI)

    Ren Yu; Alshershby, Mostafa; Qin Jiang; Hao Zuoqiang; Lin Jingquan [School of Science, Changchun University of Science and Technology, Changchun 130022 (China)

    2013-03-07T23:59:59.000Z

    Microwave guiding along single plasma filament generated through the propagation of femtosecond (fs) laser pulses in air has been demonstrated over a distance of about 6.5 cm, corresponding to a microwave signal intensity enhancement of more than 3-fold over free space propagation. The current propagation distance along the fs laser filament is in agreement with the calculations and limited by the relatively high resistance of the single plasma filament. Using a single fs laser filament to channel microwave radiation considerably alleviate requirements to the power of fs laser pulses compared to the case of the circular filaments waveguide. In addition, it can be used as a simple and non-intrusive method to obtain the basic parameters of laser-generated plasma filament.

  3. Spectral properties of microwave graphs with local absorption

    E-Print Network [OSTI]

    M. Allgaier; S. Gehler; S. Barkhofen; H. -J. Stöckmann; U. Kuhl

    2014-03-30T23:59:59.000Z

    The influence of absorption on the spectra of microwave graphs has been studied experimentally. The microwave networks were made up of coaxial cables and T junctions. First, absorption was introduced by attaching a 50 Ohm load to an additional vertex for graphs with and without time-reversal symmetry. The resulting level-spacing distributions were compared with a generalization of the Wigner surmise in the presence of open channels proposed recently by Poli et al. [Phys. Rev. Lett. 108, 174101 (2012)]. Good agreement was found using an effective coupling parameter. Second, absorption was introduced along one individual bond via a variable microwave attenuator, and the influence of absorption on the length spectrum was studied. The peak heights in the length spectra corresponding to orbits avoiding the absorber were found to be independent of the attenuation, whereas, the heights of the peaks belonging to orbits passing the absorber once or twice showed the expected decrease with increasing attenuation.

  4. Proceedings of the 36th Microwave Power Symposium, San Francisco, April 18-20, 2001

    E-Print Network [OSTI]

    Yakovlev, Vadim

    of microwave heating. Conventional impossibility to convert all microwave energy into heat leads in one of the waveguide arms of the three-port circulator. This load is also available in the market modeling of microwave heating [1]. The goal was to identify the circumstances of the stable and efficient

  5. Apparatus with moderating material for microwave heat treatment of manufactured components

    DOE Patents [OSTI]

    Ripley, Edward B. (Knoxville, TN)

    2011-05-10T23:59:59.000Z

    An apparatus for heat treating manufactured components using microwave energy and microwave susceptor material. Heat treating medium such as eutectic salts may be employed. A fluidized bed introduces process gases which may include carburizing or nitriding gases The process may be operated in a batch mode or continuous process mode. A microwave heating probe may be used to restart a frozen eutectic salt bath.

  6. A 95 GHz CLASS I METHANOL MASER SURVEY TOWARD GLIMPSE EXTENDED GREEN OBJECTS (EGOs)

    SciTech Connect (OSTI)

    Chen Xi; Shen Zhiqiang; Gan Conggui [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030 (China); Ellingsen, Simon P.; Titmarsh, Anita, E-mail: chenxi@shao.ac.cn [School of Mathematics and Physics, University of Tasmania, Hobart, Tasmania (Australia)

    2011-09-01T23:59:59.000Z

    We report the results of a systematic survey for 95 GHz class I methanol masers toward a new sample of 192 massive young stellar object candidates associated with ongoing outflows (known as extended green objects or EGOs) identified from the Spitzer Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) survey. The observations were made with the Australia Telescope National Facility (ATNF) Mopra 22 m radio telescope and resulted in the detection of 105 new 95 GHz class I methanol masers. For 92 of the sources our observations provide the first identification of a class I maser transition associated with these objects (i.e., they are new class I methanol maser sources). Our survey proves that there is indeed a high detection rate (55%) of class I methanol masers toward EGOs. Comparison of the GLIMPSE point sources associated with EGOs with and without class I methanol maser detections shows that they have similar mid-IR colors, with the majority meeting the color selection criteria -0.6 < [5.8]-[8.0] < 1.4 and 0.5 < [3.6]-[4.5] < 4.0. Investigations of the Infrared Array Camera and Multiband Imaging Photometer for Spitzer 24 {mu}m colors and the associated millimeter dust clump properties (mass and density) of the EGOs for the sub-samples based on the class of methanol masers they are associated with suggest that the stellar mass range associated with class I methanol masers extends to lower masses than for class II methanol masers, or alternatively class I methanol masers may be associated with more than one evolutionary phase during the formation of a high-mass star.

  7. LARP LHC 4.8 GHZ Schottky System Initial Commissioning with Beam

    SciTech Connect (OSTI)

    Pasquinelli, Ralph J.; /Fermilab; Jansson, Andreas; /ESS, Lund; Jones, O.Rhodri; Caspers, Fritz; /CERN

    2011-03-18T23:59:59.000Z

    The LHC Schottky system consists for four independent 4.8 GHz triple down conversion receivers with associated data acquisition systems. Each system is capable of measuring tune, chromaticity, momentum spread in either horizontal or vertical planes; two systems per beam. The hardware commissioning has taken place from spring through fall of 2010. With nominal bunch beam currents of 10{sup 11} protons, the first incoherent Schottky signals were detected and analyzed. This paper will report on these initial commissioning results. A companion paper will report on the data analysis curve fitting and remote control user interface of the system. The Schottky system for the LHC was proposed in 2004 under the auspices of the LARP collaboration. Similar systems were commissioned in 2003 in the Fermilab Tevatron and Recycler accelerators as a means of measuring tunes noninvasively. The Schottky detector is based on the stochastic cooling pickups that were developed for the Fermilab Antiproton Source Debuncher cooling upgrade completed in 2002. These slotted line waveguide pickups have the advantage of large aperture coupled with high beam coupling characteristics. For stochastic cooling, wide bandwidths are integral to cooling performance. The bandwidth of slotted waveguide pickups can be tailored by choosing the length of the pickup and slot spacing. The Debuncher project covered the 4-8 GHz band with eight bands of pickups, each with approximately 500 MHz of bandwidth. For use as a Schottky detector, bandwidths of 100-200 MHz are required for gating, resulting in higher transfer impedance than those used for stochastic cooling. Details of hardware functionality are reported previously.

  8. TGRS-2009-00082.R2 1 Abstract--The emission of bare soils at microwave L-band (1

    E-Print Network [OSTI]

    Boyer, Edmond

    will use a combined radiometer and high- resolution radar to measure surface soil moisture and freeze- thaw with sparse or no vegetation, the amount of this energy exchange is fundamentally linked with the moisture

  9. CRYOGENIC 1.5-4.5 GHz ULTRA LOW NOISE AMPLIFIER Niklas Wadefalk*, Anders Mellberg, Iltcho Angelov, Emmanuil Choumas**, Erik Kollberg,

    E-Print Network [OSTI]

    CRYOGENIC 1.5-4.5 GHz ULTRA LOW NOISE AMPLIFIER Niklas Wadefalk*, Anders Mellberg, Iltcho Angelov amplifiers with ultra-low noise and very low DC power dissipation. Amplifiers with ultra- low noise and low.5-4.5 GHz ULTRA LOW NOISE AMPLIFIER Niklas Wadefalk, Anders Mellberg, Iltcho Angelov, Emmanuil Choumas, Erik

  10. port reduces NF to 3.76 dB, which is in good agreement with the noise figure predicted without circuit losses at 5.8 GHz.

    E-Print Network [OSTI]

    Jerby, Eli

    monolithic low noise amplifier for wireless applications at 5 GHz, 1996 IEEE MMMICs Dig, pp 81­84. 9. I and procedures utilized to design an amplifier that can simultaneously provide high-gain, low-power consumption amplifier for low cost 1.5­8 GHz commercial applications, 1993 IEEE MMICS Dig, pp 13­16. 6. K.R. Gioffi

  11. 542 IEEE ELECTRON DEVICE LETTERS, VOL. 22, NO. 11, NOVEMBER 2001 A 210-GHz fT SiGe HBT With a

    E-Print Network [OSTI]

    Rieh, Jae-Sung

    542 IEEE ELECTRON DEVICE LETTERS, VOL. 22, NO. 11, NOVEMBER 2001 A 210-GHz fT SiGe HBT With a Non. Subbanna Abstract--A record 210­GHz SiGe heterojunction bipolar transistor at a collector current density by telecommunication systems. The viable materials of choice for the implementa- tion of these systems include Si(Ge

  12. Applications for Microwave Generators in the Process Industries

    E-Print Network [OSTI]

    Humphrey, J. L.; Vasilakos, N. P.

    1983-01-01T23:59:59.000Z

    . 14. Fix, S. R. "Microwave Devulcanization of Rub ber." (Goodyear Tire and Rubber Co., lincoln, NE, USA). US 4,104,205, Elastomerics, Vol. 112, No.6, pp. 1980, 38-40 (Eng). 15. Yamashita, I., Yamamoto, N., and Mima, S., "Decomposition of Waste... August 1978. 18. Novotny, D. S., et al. "Devulcanization of Sulfer-Vulcanized Elastomers." (Goodyear Tire and Rubber Co.) Ger. Offen. 2,700,306, 18 August 1977, US Appl. 646,821, 6 January 1976. 19. "Microwave Hardenable Molding Sand." (Ko matsu...

  13. Ultra high vacuum broad band high power microwave window

    DOE Patents [OSTI]

    Nguyen-Tuong, Viet (Seaford, VA); Dylla, III, Henry Frederick (Yorktown, VA)

    1997-01-01T23:59:59.000Z

    An improved high vacuum microwave window has been developed that utilizes high density polyethylene coated on two sides with SiOx, SiNx, or a combination of the two. The resultant low dielectric and low loss tangent window creates a low outgassing, low permeation seal through which broad band, high power microwave energy may be passed. No matching device is necessary and the sealing technique is simple. The features of the window are broad band transmission, ultra-high vacuum compatibility with a simple sealing technique, low voltage standing wave ratio, high power transmission and low cost.

  14. Microwave Enhanced Separation of Water-In-Oil Emulsions

    E-Print Network [OSTI]

    Fang, C. S.; Lai, P.

    MICRaVAVE ENHANCED SEPARATION OF WATER-IN-oIL EMULSIONS C.S. FANG DEPAR'lMENT OF rnEMICAL ENGINEERING UNIVERSITY OF SOUTHWESTERN LOUISIANA LAFAYE'ITE, IDUISIANA ABSTRACT The experimental data showed that viscous and stable water-in-oil.....rrental data also indicated that water-in-oil emulsion can be heated uniformly by microwaves, if the pathlength is not too long. Temperature profiles and microwave heating can be predicted reasonably well fran di electric properties and the theory...

  15. Quantum networking of microwave photons using optical fibers

    E-Print Network [OSTI]

    B. D. Clader

    2014-07-17T23:59:59.000Z

    We describe an adiabatic state transfer mechanism that allows for high-fidelity transfer of a microwave quantum state from one cavity to another through an optical fiber. The conversion from microwave frequency to optical frequency is enabled by an optomechanical transducer. The transfer process utilizes a combined dark state of the mechanical oscillator and fiber modes, making it robust against both mechanical and fiber loss. We anticipate this scheme being an enabling component of a hybrid quantum computing architecture consisting of superconducting qubits with optical interconnects.

  16. Ultra high vacuum broad band high power microwave window

    DOE Patents [OSTI]

    Nguyen-Tuong, V.; Dylla, H.F. III

    1997-11-04T23:59:59.000Z

    An improved high vacuum microwave window has been developed that utilizes high density polyethylene coated on two sides with SiOx, SiNx, or a combination of the two. The resultant low dielectric and low loss tangent window creates a low outgassing, low permeation seal through which broad band, high power microwave energy may be passed. No matching device is necessary and the sealing technique is simple. The features of the window are broad band transmission, ultra-high vacuum compatibility with a simple sealing technique, low voltage standing wave ratio, high power transmission and low cost. 5 figs.

  17. Ceramic-glass-metal seal by microwave heating

    DOE Patents [OSTI]

    Meek, T.T.; Blake, R.D.

    1983-10-04T23:59:59.000Z

    A method for producing a ceramic-glass-metal seal by microwaving, mixes a slurry of glass sealing material and coupling agent and applies same to ceramic and metal workpieces. The slurry and workpieces are then insulated and microwaved at a power, time and frequency sufficient to cause a liquid-phase reaction in the slurry. The reaction of the glass sealing material forms a chemically different seal than that which would be formed by conventional heating because it is formed by diffusion rather than by wetting of the reactants.

  18. A Wideband Single-balanced Down-mixer for the 60 GHz Band in 65 nm CMOS

    E-Print Network [OSTI]

    Boyer, Edmond

    en- gineering today is the design of low-power low-cost sili- con transceiver front performance [2], [3]. This paper presents the design and implementation of one of the basic building blocks on a differential pair employing the current bleeding technique. An integrated 60 GHz wideband passive balun allows

  19. Design and RF measurements of a 5 GHz 500 kW window for the ITER LHCD system

    E-Print Network [OSTI]

    Hillairet, Julien; Dechambre, N; Delpech, L; Ekedahl, A; Faure, N; Goniche, M; Kim, J; Larroque, S; Magne, R; Marfisi, L; Namkung, W; Park, H; Park, S; Poli, S; Vulliez, K

    2015-01-01T23:59:59.000Z

    CEA/IRFM is conducting R\\&D efforts in order to validate the critical RF components of the 5 GHz ITER LHCD system, which is expected to transmit 20 MW of RF power to the plasma. Two 5 GHz 500 kW BeO pill-box type window prototypes have been manufactured in 2012 by the PMB Company, in close collaboration with CEA/IRFM. Both windows have been validated at low power, showing good agreement between measured and modeling, with a return loss better than 32 dB and an insertion loss below 0.05 dB. This paper reports on the window RF design and the low power measurements. The high power tests up to 500kW have been carried out in March 2013 in collaboration with NFRI. Results of these tests are also reported. In the current ITER LHCD design, 20 MW Continuous Wave (CW) of Radio-Frequency power at 5 GHz are expected to be generated and transmitted to the plasma. In order to separate the vacuum vessel pressure from the cryostat waveguide pressure, forty eight 5 GHz 500kW CW windows are to be assembled on the waveguide...

  20. Fractal-Shape 40 GHz Microstrip Bandpass Filter on High-Resistivity Si for Suppression of the 2nd

    E-Print Network [OSTI]

    Tentzeris, Manos

    Fractal-Shape 40 GHz Microstrip Bandpass Filter on High-Resistivity Si for Suppression of the 2nd, the Koch fractal shape is applied for the first time to microstrip bandpass filters integrated on a high. To reduce the silicon substrate loss, high resistivity silicon (HRS) can be used. Several fractal geometries