Sample records for aperture radar sar

  1. Focused synthetic aperture radar processing of ice-sounder data collected over the Greenland ice sheet

    E-Print Network [OSTI]

    Legarsky, J.; Gogineni, Sivaprasad; Akins, T. L.

    2001-10-01T23:59:59.000Z

    We developed a synthetic aperture radar (SAR) processing algorithm for airborne/spaceborne ice-sounding radar systems and applied it to data collected in Greenland. By using focused SAR (phase-corrected coherent averaging), we improved along...

  2. Synthetic Aperture Radar Imaging with Motion Estimation and Liliana Borcea

    E-Print Network [OSTI]

    Papanicolaou, George C.

    Callaghan George Papanicolaou Abstract We introduce from first principles a synthetic aperture radar (SAR calibrated small apertures, (b) preliminary motion estimation from the data using the Wigner transform-band persistent surveillance SAR is a specific application that is covered by our analysis. Detailed numerical

  3. Imaging synthetic aperture radar

    DOE Patents [OSTI]

    Burns, Bryan L. (Tijeras, NM); Cordaro, J. Thomas (Albuquerque, NM)

    1997-01-01T23:59:59.000Z

    A linear-FM SAR imaging radar method and apparatus to produce a real-time image by first arranging the returned signals into a plurality of subaperture arrays, the columns of each subaperture array having samples of dechirped baseband pulses, and further including a processing of each subaperture array to obtain coarse-resolution in azimuth, then fine-resolution in range, and lastly, to combine the processed subapertures to obtain the final fine-resolution in azimuth. Greater efficiency is achieved because both the transmitted signal and a local oscillator signal mixed with the returned signal can be varied on a pulse-to-pulse basis as a function of radar motion. Moreover, a novel circuit can adjust the sampling location and the A/D sample rate of the combined dechirped baseband signal which greatly reduces processing time and hardware. The processing steps include implementing a window function, stabilizing either a central reference point and/or all other points of a subaperture with respect to doppler frequency and/or range as a function of radar motion, sorting and compressing the signals using a standard fourier transforms. The stabilization of each processing part is accomplished with vector multiplication using waveforms generated as a function of radar motion wherein these waveforms may be synthesized in integrated circuits. Stabilization of range migration as a function of doppler frequency by simple vector multiplication is a particularly useful feature of the invention; as is stabilization of azimuth migration by correcting for spatially varying phase errors prior to the application of an autofocus process.

  4. Joint anisotropy characterization and image formation in wide-angle synthetic aperture radar

    E-Print Network [OSTI]

    Varshney, Kush R. (Kush Raj)

    2006-01-01T23:59:59.000Z

    Imagery formed from wide-angle synthetic aperture radar (SAR) measurements has fine cross-range resolution in principle. However, conventional SAR image formation techniques assume isotropic scattering, which is not valid ...

  5. Motion Measurement for Synthetic Aperture Radar.

    SciTech Connect (OSTI)

    Doerry, Armin W.

    2015-01-01T23:59:59.000Z

    Synthetic Aperture Radar (SAR) measures radar soundings from a set of locations typically along the flight path of a radar platform vehicle. Optimal focusing requires precise knowledge of the sounding source locations in 3 - D space with respect to the target scene. Even data driven focusing techniques (i.e. autofocus) requires some degree of initial fidelity in the measurements of the motion of the radar. These requirements may be quite stringent especially for fine resolution, long ranges, and low velocities. The principal instrument for measuring motion is typically an Inertial Measurement Unit (IMU), but these instruments have inherent limi ted precision and accuracy. The question is %22How good does an IMU need to be for a SAR across its performance space?%22 This report analytically relates IMU specifications to parametric requirements for SAR. - 4 - Acknowledgements Th e preparation of this report is the result of a n unfunded research and development activity . Although this report is an independent effort, it draws heavily from limited - release documentation generated under a CRADA with General Atomics - Aeronautical System, Inc. (GA - ASI), and under the Joint DoD/DOE Munitions Program Memorandum of Understanding. Sandia National Laboratories is a multi - program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of En ergy's National Nuclear Security Administration under contract DE - AC04 - 94AL85000.

  6. Synthetic aperture radar and interferometry development at Sandia National Laboratories

    SciTech Connect (OSTI)

    NONE

    1993-04-01T23:59:59.000Z

    Environmental monitoring, earth-resource mapping, and military systems require broad-area imaging at high resolutions. Many times the imagery must be acquired in inclement weather or during night as well as day. Synthetic aperture radar (SAR) provides such a capability. SAR systems take advantage of the long-range propagation characteristics of radar signals and the complex information processing capability of modern digital electronics to provide high resolution imagery. SAR complements photographic and other optical imaging capabilities because of the minimum constrains on time-of-day and atmospheric conditions and because of the unique responses of terrain and cultural targets to radar frequencies. Interferometry is a method for generating a three-dimensional image of terrain. The height projection is obtained by acquiring two SAR images from two slightly differing locations. It is different from the common method of stereoscopic imaging for topography. The latter relies on differing geometric projections for triangulation to define the surface geometry whereas interferometry relies on differences in radar propagation times between the two SAR locations. This paper presents the capabilities of SAR, explains how SAR works, describes a few SAR applications, provides an overview of SAR development at Sandia, and briefly describes the motion compensation subsystem.

  7. Synthetic Aperture Radar Imaging with Motion Estimation and , T. Callaghan1

    E-Print Network [OSTI]

    Borcea, Liliana

    principles a synthetic aperture radar (SAR) imaging and target motion estimation method that is combined of the data into properly calibrated small apertures, (b) motion or platform trajectory perturbation estimation process. X-band persistent surveillance SAR is a specific application that is covered by our

  8. Antarctica X-band MiniSAR crevasse detection radar : final report.

    SciTech Connect (OSTI)

    Sander, Grant J.; Bickel, Douglas Lloyd

    2007-09-01T23:59:59.000Z

    This document is the final report for the Antarctica Synthetic Aperture Radar (SAR) Project. The project involved the modification of a Sandia National Laboratories MiniSAR system to operate at X-band in order to assess the feasibility of an airborne radar to detect crevasses in Antarctica. This radar successfully detected known crevasses at various geometries. The best results were obtained for synthetic aperture radar resolutions of at most one foot and finer. In addition to the main goal of detecting crevasses, the radar was used to assess conops for a future operational radar. The radar scanned large areas to identify potential safe landing zones. In addition, the radar was used to investigate looking at objects on the surface and below the surface of the ice. This document includes discussion of the hardware development, system capabilities, and results from data collections in Antarctica.

  9. Synthetic aperture design for increased SAR image rate

    DOE Patents [OSTI]

    Bielek, Timothy P. (Albuquerque, NM); Thompson, Douglas G. (Albuqerque, NM); Walker, Bruce C. (Albuquerque, NM)

    2009-03-03T23:59:59.000Z

    High resolution SAR images of a target scene at near video rates can be produced by using overlapped, but nevertheless, full-size synthetic apertures. The SAR images, which respectively correspond to the apertures, can be analyzed in sequence to permit detection of movement in the target scene.

  10. Abstract--In the design of a spaceborne Synthetic Aperture RADAR mission with multiple modes and swaths, like the

    E-Print Network [OSTI]

    Gesbert, David

    the modes. Index Terms-- Synthetic Aperture Radar, STRIPMAP, TOPSAR. Conference topic: SAR/ISAR I Sophia-Antipolis cedex, France. mail: lorenzo.maggi@eurecom.fr calibration and the processing. In order of a spaceborne SAR. Let us refer to the geometry of Fig. 1.a, where we assumed for simplicity flat earth

  11. Basics of Polar-Format algorithm for processing Synthetic Aperture Radar images.

    SciTech Connect (OSTI)

    Doerry, Armin Walter

    2012-05-01T23:59:59.000Z

    The purpose of this report is to provide a background to Synthetic Aperture Radar (SAR) image formation using the Polar Format (PFA) processing algorithm. This is meant to be an aid to those tasked to implement real-time image formation using the Polar Format processing algorithm.

  12. Soil-penetrating synthetic aperture radar

    SciTech Connect (OSTI)

    Boverie, B.; Brock, B.C.; Doerry, A.W.

    1994-12-01T23:59:59.000Z

    This report summarizes the results for the first year of a two year Laboratory Directed Research and Development (LDRD) effort. This effort included a system study, preliminary data acquisition, and preliminary algorithm development. The system study determined the optimum frequency and bandwidth, surveyed soil parameters and targets, and defined radar cross section in lossy media. The data acquisition imaged buried objects with a rail-SAR. Algorithm development included a radar echo model, three-dimensional processing, sidelobe optimization, phase history data interpolation, and clutter estimation/cancellation.

  13. IFP V4.0:a polar-reformatting image formation processor for synthetic aperture radar.

    SciTech Connect (OSTI)

    Eichel, Paul H.

    2005-09-01T23:59:59.000Z

    IFP V4.0 is the fourth generation of an extraordinarily powerful and flexible image formation processor for spotlight mode synthetic aperture radar. It has been successfully utilized in processing phase histories from numerous radars and has been instrumental in the development of many new capabilities for spotlight mode SAR. This document provides a brief history of the development of IFP, a full exposition of the signal processing steps involved, and a short user's manual for the software implementing this latest iteration.

  14. Semi-empirical calibration of the Integral Equation Model for SAR data in C-band and cross polarization using radar images and field

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 1 Semi-empirical calibration of the Integral Equation Model for SAR data in C-band and cross and roughness) from Synthetic Aperture Radar (SAR) images requires the use of well-calibrated backscattering was found between the backscattering coefficient provided by the SAR and that simulated by the calibrated

  15. Correction of motion measurement errors beyond the range resolution of a synthetic aperture radar

    DOE Patents [OSTI]

    Doerry, Armin W. (Albuquerque, NM); Heard, Freddie E. (Albuquerque, NM); Cordaro, J. Thomas (Albuquerque, NM)

    2008-06-24T23:59:59.000Z

    Motion measurement errors that extend beyond the range resolution of a synthetic aperture radar (SAR) can be corrected by effectively decreasing the range resolution of the SAR in order to permit measurement of the error. Range profiles can be compared across the slow-time dimension of the input data in order to estimate the error. Once the error has been determined, appropriate frequency and phase correction can be applied to the uncompressed input data, after which range and azimuth compression can be performed to produce a desired SAR image.

  16. Synthetic aperture integration (SAI) algorithm for SAR imaging

    DOE Patents [OSTI]

    Chambers, David H; Mast, Jeffrey E; Paglieroni, David W; Beer, N. Reginald

    2013-07-09T23:59:59.000Z

    A method and system for detecting the presence of subsurface objects within a medium is provided. In some embodiments, the imaging and detection system operates in a multistatic mode to collect radar return signals generated by an array of transceiver antenna pairs that is positioned across the surface and that travels down the surface. The imaging and detection system pre-processes the return signal to suppress certain undesirable effects. The imaging and detection system then generates synthetic aperture radar images from real aperture radar images generated from the pre-processed return signal. The imaging and detection system then post-processes the synthetic aperture radar images to improve detection of subsurface objects. The imaging and detection system identifies peaks in the energy levels of the post-processed image frame, which indicates the presence of a subsurface object.

  17. A model for forming airborne synthetic aperture radar images of underground targets

    SciTech Connect (OSTI)

    Doerry, A.W.

    1994-01-01T23:59:59.000Z

    Synthetic Aperture Radar (SAR) from an airborne platform has been proposed for imaging targets beneath the earth`s surface. The propagation of the radar`s energy within the ground, however, is much different than in the earth`s atmosphere. The result is signal refraction, echo delay, propagation losses, dispersion, and volumetric scattering. These all combine to make SAR image formation from an airborne platform much more challenging than a surface imaging counterpart. This report treats the ground as a lossy dispersive half-space, and presents a model for the radar echo based on measurable parameters. The model is then used to explore various imaging schemes, and image properties. Dynamic range is discussed, as is the impact of loss on dynamic range. Modified window functions are proposed to mitigate effects of sidelobes of shallow targets overwhelming deeper targets.

  18. PoroTomo Subtask 3.4 Analysis of existing InSAR data

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

    Kurt Feigl

    Attributes of synthetic aperture radar (SAR) data acquired by TerraSAR-X and TandemX satellite missions and archived at WINSAR facility.

  19. PoroTomo Subtask 3.4 Analysis of existing InSAR data

    SciTech Connect (OSTI)

    Kurt Feigl

    2014-12-26T23:59:59.000Z

    Attributes of synthetic aperture radar (SAR) data acquired by TerraSAR-X and TandemX satellite missions and archived at WINSAR facility.

  20. Synthetic Aperture Radar Interferometry with 3 satellites

    E-Print Network [OSTI]

    Wong, Wallace D. (Wallace Dazheng)

    2005-01-01T23:59:59.000Z

    Our study investigates interferometric SAR (InSAR) post-processing height retrieval techniques. We explore the possible improvements by adding a third satellite to the two already in orbit, and examine some potential uses ...

  1. Inversion of synthetic aperture radar interferograms for sources...

    Open Energy Info (EERE)

    synthetic aperture radar interferograms for sources of production-related subsidence at the Dixie Valley geothermal field Jump to: navigation, search OpenEI Reference LibraryAdd to...

  2. Bistatic SAR: Proof of Concept.

    SciTech Connect (OSTI)

    Yocky, David A.; Doren, Neall E.; Bacon, Terry A.; Wahl, Daniel E.; Eichel, Paul H.; Jakowatz, Charles V,; Delaplain, Gilbert G.; Dubbert, Dale F.; Tise, Bertice L.; White, Kyle R.

    2014-10-01T23:59:59.000Z

    Typical synthetic aperture RADAR (SAR) imaging employs a co-located RADAR transmitter and receiver. Bistatic SAR imaging separates the transmitter and receiver locations. A bistatic SAR configuration allows for the transmitter and receiver(s) to be in a variety of geometric alignments. Sandia National Laboratories (SNL) / New Mexico proposed the deployment of a ground-based RADAR receiver. This RADAR receiver was coupled with the capability of digitizing and recording the signal collected. SNL proposed the possibility of creating an image of targets the illuminating SAR observes. This document describes the developed hardware, software, bistatic SAR configuration, and its deployment to test the concept of a ground-based bistatic SAR. In the proof-of-concept experiments herein, the RADAR transmitter will be a commercial SAR satellite and the RADAR receiver will be deployed at ground level, observing and capturing RADAR ground/targets illuminated by the satellite system.

  3. Comparing range data across the slow-time dimension to correct motion measurement errors beyond the range resolution of a synthetic aperture radar

    DOE Patents [OSTI]

    Doerry, Armin W. (Albuquerque, NM); Heard, Freddie E. (Albuquerque, NM); Cordaro, J. Thomas (Albuquerque, NM)

    2010-08-17T23:59:59.000Z

    Motion measurement errors that extend beyond the range resolution of a synthetic aperture radar (SAR) can be corrected by effectively decreasing the range resolution of the SAR in order to permit measurement of the error. Range profiles can be compared across the slow-time dimension of the input data in order to estimate the error. Once the error has been determined, appropriate frequency and phase correction can be applied to the uncompressed input data, after which range and azimuth compression can be performed to produce a desired SAR image.

  4. On the detection of crevasses in glacial ice with synthetic-aperture radar.

    SciTech Connect (OSTI)

    Brock, Billy C.

    2010-02-01T23:59:59.000Z

    The intent of this study is to provide an analysis of the scattering from a crevasse in Antarctic ice, utilizing a physics-based model for the scattering process. Of primary interest is a crevasse covered with a snow bridge, which makes the crevasse undetectable in visible-light images. It is demonstrated that a crevasse covered with a snow bridge can be visible in synthetic-aperture-radar (SAR) images. The model of the crevasse and snow bridge incorporates a complex dielectric permittivity model for dry snow and ice that takes into account the density profile of the glacier. The surface structure is based on a fractal model that can produce sastrugi-like features found on the surface of Antarctic glaciers. Simulated phase histories, computed with the Shooting and Bouncing Ray (SBR) method, are processed into SAR images. The viability of the SBR method for predicting scattering from a crevasse covered with a snow bridge is demonstrated. Some suggestions for improving the model are given.

  5. A framework for comparing geomechanical models of InSAR-measured surface deformation

    E-Print Network [OSTI]

    De Laplante, Neil Edward James

    2011-01-01T23:59:59.000Z

    High-quality Interferometric Synthetic Aperture Radar (InSAR) surface deformation data for field sites around the world has become widely available over the past decade. Geomechanical models based on InSAR data occur ...

  6. A High Resolution, Light-Weight, Synthetic Aperture Radar for UAV Application

    SciTech Connect (OSTI)

    Doerry, A.W.; Hensley, W.H.; Stence, J.; Tsunoda, S.I. Pace, F.; Walker, B,C.; Woodring, M.

    1999-05-27T23:59:59.000Z

    (U) Sandia National Laboratories in collaboration with General Atomics (GA) has designed and built a high resolution, light-weight, Ku-band Synthetic Aperture Radar (SAR) known as "Lynx". Although Lynx can be operated on a wide variety of manned and unmanned platforms, its design is optimized for use on medium altitude Unmanned Aerial Vehicles (UAVS). In particular, it can be operated on the Predator, I-GNAT, and Prowler II platforms manufactured by GA. (U) The radar production weight is less than 120 lb and operates within a 3 GHz band from 15.2 GHz to 18.2 GHz with a peak output power of 320 W. Operating range is resolution and mode dependent but can exceed 45 km in adverse weather (4 mm/hr rain). Lynx has operator selectable resolution and is capable of 0.1 m resolution in spotlight mode and 0.3 m resolution in stripmap mode, over substantial depression angles (5 to 60 deg) and squint angles (broadside ±45 deg). Real-time Motion Compensation is implemented to allow high-quality image formation even during vehicle turns and other maneuvers.

  7. Sandia National Laboratories: Synthetic Aperture Radar (SAR) Imagery

    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 Sol HomeFacebook Twitter YouTubeCenters:Facebook Twitter YouTubeFacebook

  8. Synthetic Aperture Radar Persistent Scatterer Interferometry (PSInSAR) |

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro Industries PvtStratosolar Jump to:Holdings Co08.0 - WarehousesSymerton,EV Jump to:Open Energy

  9. Method and apparatus for reducing range ambiguity in synthetic aperture radar

    DOE Patents [OSTI]

    Kare, Jordin T. (San Ramon, CA)

    1999-10-26T23:59:59.000Z

    A modified Synthetic Aperture Radar (SAR) system with reduced sensitivity to range ambiguities, and which uses secondary receiver channels to detect the range ambiguous signals and subtract them from the signal received by the main channel. Both desired and range ambiguous signals are detected by a main receiver and by one or more identical secondary receivers. All receivers are connected to a common antenna with two or more feed systems offset in elevation (e.g., a reflector antenna with multiple feed horns or a phased array with multiple phase shift networks. The secondary receiver output(s) is (are) then subtracted from the main receiver output in such a way as to cancel the ambiguous signals while only slightly attenuating the desired signal and slightly increasing the noise in the main channel, and thus does not significantly affect the desired signal. This subtraction may be done in real time, or the outputs of the receivers may be recorded separately and combined during signal processing.

  10. Exploring scatterer anisotrophy in synthetic aperture radar via sub-aperture analysis

    E-Print Network [OSTI]

    Kim, Andrew J

    2001-01-01T23:59:59.000Z

    Scattering from man-made objects in SAR imagery exhibits aspect and frequency dependencies which are not always well modeled by standard SAR imaging techniques based on the ideal point scattering model. This is particularly ...

  11. Design and implementation of a Synthetic Aperture Radar for Open Skies (SAROS) aboard a C-135 aircraft

    SciTech Connect (OSTI)

    Cooper, D.W.; Murphy, M. [Sandia National Labs., Albuquerque, NM (United States); Rimmel, G. [Loral Defense Systems, Litchfield, AZ (United States)

    1994-08-01T23:59:59.000Z

    NATO and former Warsaw Pact nations have agreed to allow overflights of their countries in the interest of easing world tension. The United States has decided to implement two C-135 aircraft with a Synthetic Aperture Radar (SAR) that has a 3-meter resolution. This work is being sponsored by the Defense Nuclear Agency (DNA) and will be operational in Fall 1995. Since the SAR equipment must be exportable to foreign nations, a 20-year-old UPD-8 analog SAR system was selected as the front-end and refurbished for this application by Loral Defense Systems. Data processing is being upgraded to a currently exportable digital design by Sandia National Laboratories. Amplitude and phase histories will be collected during these overflights and digitized on VHS cassettes. Ground stations will use reduction algorithms to process the data and convert it to magnitude-detected images for member nations. System Planning Corporation is presently developing a portable ground station for use on the demonstration flights. Aircraft integration into the C-135 aircraft is being done by the Air Force at Wright-Patterson AFB, Ohio.

  12. ARKTOS: An intelligent system for SAR sea ice image classification

    E-Print Network [OSTI]

    Soh, L. K.; Tsatsoulis, Costas; Gineris, D.; Bertoia, C.

    2004-01-01T23:59:59.000Z

    We present an intelligent system for satellite sea ice image analysis named Advanced Reasoning using Knowledge for T ping Of Sea ice (ARKTOS). ARKTOS performs fully automated analysis of synthetic aperture radar (SAR) sea ice images by mimicking...

  13. Three-dimensional subsurface imaging synthetic aperture radar (3D SISAR). Final report, September 22, 1993--September 22, 1996

    SciTech Connect (OSTI)

    NONE

    1998-12-31T23:59:59.000Z

    The concept developed under this applied research and development contract is a novel Ground Penetrating Radar system capable of remotely detecting, analyzing, and mapping buried waste containers from a mobile platform. From the testing and analysis performed to date, the 3-D SISAR has achieved the detection, accurate location, and three-dimensional imaging of buried test objects from a stand-off geometry. Tests have demonstrated that underground objects have been located to within 0.1 meter of their actual position. This work validates that the key elements of the approach are performing as anticipated. The stand-off synthetic aperture radar (SAR) methodology has been demonstrated to be a feasible approach as a remote sensing technique. The radar sensor constructed under this project is providing adequate quality data for imaging, and the matched filters have been demonstrated to provide enhanced target detection. Additional work is on-going in the area of underground propagation and scattering phenomena to provide enhanced depth performance, as the current imaging results have been limited to a few feet of depth underground.

  14. Cassini Radio Detection and Ranging (RADAR): Earth and Venus observations

    E-Print Network [OSTI]

    Lorenz, Ralph D.

    of operation is as a synthetic aperture radar (SAR) mapper at Titan, with the fan-shaped beam dragged across of incidence angles. During all of the active modes, SAR, altimeter, and scat- terometer, the microwave power but rather was operated to obtain calibration data and rehearse instrument operations. 2. Venus The RADAR

  15. SAR image effects on coherence and coherence estimation.

    SciTech Connect (OSTI)

    Bickel, Douglas Lloyd

    2014-01-01T23:59:59.000Z

    Radar coherence is an important concept for imaging radar systems such as synthetic aperture radar (SAR). This document quantifies some of the effects in SAR which modify the coherence. Although these effects can disrupt the coherence within a single SAR image, this report will focus on the coherence between separate images, such as for coherent change detection (CCD) processing. There have been other presentations on aspects of this material in the past. The intent of this report is to bring various issues that affect the coherence together in a single report to support radar engineers in making decisions about these matters.

  16. Finding Large Aperture Fractures in Geothermal Resource Areas Using A Three-Component Long-Offset Surface Seismic Survey, PSInSAR, and Kinematic Analysis

    Broader source: Energy.gov [DOE]

    Fining Large Aperture Fractures in Geothermal Resource Areas Using A Three-Component Long-Offset Surface Seismic Survey, PSInSAR, and Kinematic Analysis presentation at the April 2013 peer review meeting held in Denver, Colorado.

  17. Reflectors for SAR performance testing.

    SciTech Connect (OSTI)

    Doerry, Armin Walter

    2008-01-01T23:59:59.000Z

    Synthetic Aperture Radar (SAR) performance testing and estimation is facilitated by observing the system response to known target scene elements. Trihedral corner reflectors and other canonical targets play an important role because their Radar Cross Section (RCS) can be calculated analytically. However, reflector orientation and the proximity of the ground and mounting structures can significantly impact the accuracy and precision with which measurements can be made. These issues are examined in this report.

  18. Forming rotated SAR images by real-time motion compensation.

    SciTech Connect (OSTI)

    Doerry, Armin Walter

    2012-12-01T23:59:59.000Z

    Proper waveform parameter selection allows collecting Synthetic Aperture Radar (SAR) phase history data on a rotated grid in the Fourier Space of the scene being imaged. Subsequent image formation preserves the rotated geometry to allow SAR images to be formed at arbitrary rotation angles without the use of computationally expensive interpolation or resampling operations. This should be useful where control of image orientation is desired such as generating squinted stripmaps and VideoSAR applications, among others.

  19. Bistatic SAR: Signal Processing and Image Formation.

    SciTech Connect (OSTI)

    Wahl, Daniel E.; Yocky, David A.

    2014-10-01T23:59:59.000Z

    This report describes the significant processing steps that were used to take the raw recorded digitized signals from the bistatic synthetic aperture RADAR (SAR) hardware built for the NCNS Bistatic SAR project to a final bistatic SAR image. In general, the process steps herein are applicable to bistatic SAR signals that include the direct-path signal and the reflected signal. The steps include preprocessing steps, data extraction to for a phase history, and finally, image format. Various plots and values will be shown at most steps to illustrate the processing for a bistatic COSMO SkyMed collection gathered on June 10, 2013 on Kirtland Air Force Base, New Mexico.

  20. Analyzing lead information from SAR images

    E-Print Network [OSTI]

    Van Dyne, M. M.; Tsatsoulis, Costas; Fetterer, F.

    1998-03-01T23:59:59.000Z

    means of gathering important information about the sea ice cover and its climatic influence, This paper describes: 1) a method for extracting and analyzing leads from ERS-1 synthetic aperture radar (SAR) images classified by ice type and 2) the results...

  1. SAR-BASED WIND CLIMATOLOGY FOR WIND TURBINES Merete Bruun Christiansen(1)

    E-Print Network [OSTI]

    SAR-BASED WIND CLIMATOLOGY FOR WIND TURBINES Merete Bruun Christiansen(1) , Charlotte Bay Hasager(1) , Donald Thompson(2) , Lars Boye Hansen(3) (1) Wind Energy Department, Risø National Laboratory, Technical, Denmark ABSTRACT Wind fields extracted from synthetic aperture radar (SAR) imagery are used to analyze

  2. Coastal Wind Mapping from Satellite SAR: Possibilities and Limitations Charlotte Bay Hasager and Merete Bruun Christiansen

    E-Print Network [OSTI]

    - 21 - Coastal Wind Mapping from Satellite SAR: Possibilities and Limitations Charlotte Bay Hasager and Merete Bruun Christiansen Risø National Laboratory, Wind Energy Department, Meteorology Program, VEA-118 Abstract Satellite remote sensing of ocean wind fields from Synthetic Aperture Radar (SAR) observations

  3. Detection of Oil Spills in SAR Images Using Wavelets and Region Growing

    E-Print Network [OSTI]

    de Figueiredo, Luiz Henrique

    Detection of Oil Spills in SAR Images Using Wavelets and Region Growing RÉGIA T. S. ARAÚJO, FÁTIMA an algorithm to detect oil spills in Synthetic Aperture Radar (SAR) images that can be used to support sensing of environmental disasters. Spillage of oil in coastal waters can be a catastrophic event

  4. Discontinuous Non-Rigid Motion Analysis of Sea Ice using C-Band Synthetic Aperture Radar Satellite Imagery

    E-Print Network [OSTI]

    Delaware, University of

    Discontinuous Non-Rigid Motion Analysis of Sea Ice using C-Band Synthetic Aperture Radar Satellite@cis.udel.edu Cathleen Geiger Snow and Ice Branch USACRREL 72 Lyme Rd, Hanover, NH 03755 cathleen@cis.udel.edu Abstract Sea-ice motion consists of complex non-rigid motions in- volving continuous, piece-wise continuous

  5. Progress reports for October 1994 -- Joint UK/US Radar Program

    SciTech Connect (OSTI)

    Twogood, R.E.; Brase, J.M.; Mantrom, D.D.; Chambers, D.H.; Robey, H.F.

    1994-11-18T23:59:59.000Z

    This report gives the principle investigator, objectives, recent accomplishments, milestones for reporting period, expected milestones for ensuing period, other issues and planned expenditures for each of the following programs: airborne RAR/SAR; radar data processor; ground-based SAR signal processing workstation; static airborne radar; multi-aperture space-time array radar; radar field experiments; data analysis and detection theory; management; E-2C radar data analysis; modeling and analysis; current meter array; UCSB wave tank; stratified flow facility; and IR sensor system. Finally the budget status is given.

  6. IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 47, NO. 6, JUNE 2009 1777 Cassini RADAR Sequence Planning and

    E-Print Network [OSTI]

    Goddard III, William A.

    in the Saturn system. Two SAR modes are used for high- and medium-resolution (300­1000 m) imaging of Titan, and calibration observations have provided an absolute calibration good to about 1.3 dB. Relative uncertainties, radiometer, synthetic aperture radar (SAR). I. INTRODUCTION THE Cassini­Huygens mission to Saturn

  7. Decreasing range resolution of a SAR image to permit correction of motion measurement errors beyond the SAR range resolution

    DOE Patents [OSTI]

    Doerry, Armin W. (Albuquerque, NM); Heard, Freddie E. (Albuquerque, NM); Cordaro, J. Thomas (Albuquerque, NM)

    2010-07-20T23:59:59.000Z

    Motion measurement errors that extend beyond the range resolution of a synthetic aperture radar (SAR) can be corrected by effectively decreasing the range resolution of the SAR in order to permit measurement of the error. Range profiles can be compared across the slow-time dimension of the input data in order to estimate the error. Once the error has been determined, appropriate frequency and phase correction can be applied to the uncompressed input data, after which range and azimuth compression can be performed to produce a desired SAR image.

  8. Estimating IMU heading error from SAR images.

    SciTech Connect (OSTI)

    Doerry, Armin Walter

    2009-03-01T23:59:59.000Z

    Angular orientation errors of the real antenna for Synthetic Aperture Radar (SAR) will manifest as undesired illumination gradients in SAR images. These gradients can be measured, and the pointing error can be calculated. This can be done for single images, but done more robustly using multi-image methods. Several methods are provided in this report. The pointing error can then be fed back to the navigation Kalman filter to correct for problematic heading (yaw) error drift. This can mitigate the need for uncomfortable and undesired IMU alignment maneuvers such as S-turns.

  9. Radar transponder apparatus and signal processing technique

    DOE Patents [OSTI]

    Axline, Jr., Robert M. (Albuquerque, NM); Sloan, George R. (Albuquerque, NM); Spalding, Richard E. (Albuquerque, NM)

    1996-01-01T23:59:59.000Z

    An active, phase-coded, time-grating transponder and a synthetic-aperture radar (SAR) and signal processor means, in combination, allow the recognition and location of the transponder (tag) in the SAR image and allow communication of information messages from the transponder to the SAR. The SAR is an illuminating radar having special processing modifications in an image-formation processor to receive an echo from a remote transponder, after the transponder receives and retransmits the SAR illuminations, and to enhance the transponder's echo relative to surrounding ground clutter by recognizing special transponder modulations from phase-shifted from the transponder retransmissions. The remote radio-frequency tag also transmits information to the SAR through a single antenna that also serves to receive the SAR illuminations. Unique tag-modulation and SAR signal processing techniques, in combination, allow the detection and precise geographical location of the tag through the reduction of interfering signals from ground clutter, and allow communication of environmental and status information from said tag to be communicated to said SAR.

  10. Automatic compensation of antenna beam roll-off in SAR images.

    SciTech Connect (OSTI)

    Doerry, Armin Walter

    2006-04-01T23:59:59.000Z

    The effects of a non-uniform antenna beam are sometimes visible in Synthetic Aperture Radar (SAR) images. This might be due to near-range operation, wide scenes, or inadequate antenna pointing accuracy. The effects can be mitigated in the SAR image by fitting very a simple model to the illumination profile and compensating the pixel brightness accordingly, in an automated fashion. This is accomplished without a detailed antenna pattern calibration, and allows for drift in the antenna beam alignments.

  11. Shallow intraplate earthquakes in Western Australia observed by Interferometric Synthetic Aperture Radar

    E-Print Network [OSTI]

    Tregoning, Paul

    Shallow intraplate earthquakes in Western Australia observed by Interferometric Synthetic Aperture earthquakes in a stable continental region of southwest Western Australia. Both small-magnitude events occur with tectonic processes in this area of Western Australia often initiate in the upper 1 km of crust. Citation

  12. Compressive Radar with Off-Grid and Extended Targets

    E-Print Network [OSTI]

    Fannjiang, Albert

    2012-01-01T23:59:59.000Z

    Compressed sensing (CS) schemes are proposed for monostatic as well as synthetic aperture radar (SAR) imaging of sparse targets with chirps. In particular, a simple method is developed to improve performance with off-grid targets. Tomographic formulation of spotlight SAR is analyzed by CS methods with several bases and under various bandwidth constraints. Performance guarantees are established via coherence bound and the restricted isometry property. CS analysis provides a fresh and clear perspective on how to optimize temporal and angular samplings for spotlight SAR.

  13. The effect of topography on SAR calibration

    SciTech Connect (OSTI)

    Zyl, J.J. van; Chapman, B.D.; Dubois, P. (California Inst. of Tech., Pasadena, CA (United States). Jet Propulsion Lab.); Shi, Jiancheng (Univ. of California, Santa Barbara, CA (United States))

    1993-09-01T23:59:59.000Z

    During normal synthetic aperture radar (SAR) processing, a flat earth is assumed when performing radiometric corrections such as antenna pattern and scattering area removal. Here the authors examine the effects of topographic variations on these corrections. Local slopes will cause the actual scattering area to be different from that calculated using the flat earth assumption. It is shown that this effect, which is present for both airborne and spaceborne SAR data, may easily cause calibration errors larger than a decibel. Ignoring the topography during antenna pattern removal is expected to be negligible for spaceborne SAR's. In this paper they show how these effects can be taken into account if a digital elevation model is available for the imaged area. It is also shown that not taking the topography into account during antenna pattern removal introduces polarimetric calibration errors.

  14. Interseismic deformation and creep along the central section of the North Anatolian Fault (Turkey): InSAR observations

    E-Print Network [OSTI]

    Sandwell, David T.

    Interseismic deformation and creep along the central section of the North Anatolian Fault (Turkey Anatolian Fault (NAF) in Turkey using interferometric synthetic aperture radar data from the Advanced Land Anatolian Fault (Turkey): InSAR observations and implications for rate-and-state friction properties, J

  15. Improvement of radar ice-thickness measurements of Greenland outlet glaciers using SAR processing

    E-Print Network [OSTI]

    Braaten, David A.; Gogineni, S. Prasad; Tammana, Dilip; Namburi, Saikiran; Paden, John; Gurumoorthy, Krishna K.

    2002-01-01T23:59:59.000Z

    Extensive aircraft-based radar ice-thickness measurements over the interior and outlet-glacier regions of the Greenland ice sheet have been obtained by the University of Kansas since 1993, with the latest airborne surveys conducted in May 2001...

  16. Detecting and monitoring UCG subsidence with InSAR

    SciTech Connect (OSTI)

    Mellors, R J; Foxall, W; Yang, X

    2012-03-23T23:59:59.000Z

    The use of interferometric synthetic aperture radar (InSAR) to measure surface subsidence caused by Underground Coal Gasification (UCG) is tested. InSAR is a remote sensing technique that uses Synthetic Aperture Radar images to make spatial images of surface deformation and may be deployed from satellite or an airplane. With current commercial satellite data, the technique works best in areas with little vegetation or farming activity. UCG subsidence is generally caused by roof collapse, which adversely affects UCG operations due to gas loss and is therefore important to monitor. Previous studies have demonstrated the usefulness of InSAR in measuring surface subsidence related to coal mining and surface deformation caused by a coal mining roof collapse in Crandall Canyon, Utah is imaged as a proof-of-concept. InSAR data is collected and processed over three known UCG operations including two pilot plants (Majuba, South Africa and Wulanchabu, China) and an operational plant (Angren, Uzbekistan). A clear f eature showing approximately 7 cm of subsidence is observed in the UCG field in Angren. Subsidence is not observed in the other two areas, which produce from deeper coal seams and processed a smaller volume. The results show that in some cases, InSAR is a useful tool to image UCG related subsidence. Data from newer satellites and improved algorithms will improve effectiveness.

  17. BioSAR Airborne Biomass Sensing System

    SciTech Connect (OSTI)

    Graham, R.L.; Johnson, P.

    2007-05-24T23:59:59.000Z

    This CRADA was developed to enable ORNL to assist American Electronics, Inc. test a new technology--BioSAR. BioSAR is a an airborne, low frequency (80-120 MHz {approx} FM radio frequencies) synthetic aperture radar (SAR) technology which was designed and built for NASA by ZAI-Amelex under Patrick Johnson's direction. At these frequencies, leaves and small branches are nearly transparent and the majority of the energy reflected from the forest and returned to the radar is from the tree trunks. By measuring the magnitude of the back scatter, the volume of the tree trunk and therefore the biomass of the trunks can be inferred. The instrument was successfully tested on tropical rain forests in Panama. Patrick Johnson, with American Electronics, Inc received a Phase II SBIR grant from DOE Office of Climate Change to further test and refine the instrument. Mr Johnson sought ORNL expertise in measuring forest biomass in order for him to further validate his instrument. ORNL provided ground truth measurements of forest biomass at three locations--the Oak Ridge Reservation, Weyerhaeuser Co. commercial pine plantations in North Carolina, and American Energy and Power (AEP) Co. hardwood forests in southern Ohio, and facilitated flights over these forests. After Mr. Johnson processed the signal data from BioSAR instrument, the processed data were given to ORNL and we attempted to derive empirical relationships between the radar signals and the ground truth forest biomass measurements using standard statistical techniques. We were unsuccessful in deriving such relationships. Shortly before the CRADA ended, Mr Johnson discovered that FM signal from local radio station broadcasts had interfered with the back scatter measurements such that the bulk of the signal received by the BioSAR instrument was not backscatter from the radar but rather was local radio station signals.

  18. Comparison between backscattered TerraSAR signals and simulations from the radar backscattering models IEM, Oh, and Dubois

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    for a use of IEM in the inversion of TerraSAR data. A semi-empirical calibration of IEM was done in X-band. Good agreement was found between the TerraSAR data and the simulations using the calibrated version propose an extension of the calibration of IEM model to SAR data in X-band. II. EXPERIMENTAL DATA A. Study

  19. Time Reversal Synthetic Aperture Radar Imaging In Multipath Yuanwei Jin, Jose M.F. Moura, and Nicholas O'Donoughue

    E-Print Network [OSTI]

    Moura, José

    Michael T. Mulford and Alphonso A. Samuel Raytheon Missile Systems Tucson, AZ 85734 Abstract Conventional by a rail-mounted SAR sensor operated by Raytheon. 1 Introduction Many data adaptive high resolution-mounted SAR sensor at Raytheon in a rich scattering environment. 2 Mathematical Description of TR

  20. Initial assessment of an airborne Ku-band polarimetric SAR.

    SciTech Connect (OSTI)

    Raynal, Ann Marie; Doerry, Armin Walter

    2013-02-01T23:59:59.000Z

    Polarimetric synthetic aperture radar (SAR) has been used for a variety of dual-use research applications since the 1940's. By measuring the direction of the electric field vector from radar echoes, polarimetry may enhance an analyst's understanding of scattering effects for both earth monitoring and tactical surveillance missions. Polarimetry may provide insight into surface types, materials, or orientations for natural and man-made targets. Polarimetric measurements may also be used to enhance the contrast between scattering surfaces such as man-made objects and their surroundings. This report represents an initial assessment of the utility of, and applications for, polarimetric SAR at Ku-band for airborne or unmanned aerial systems.

  1. Target Detection in SAR Images Based on a Level Set Approach

    SciTech Connect (OSTI)

    Marques, Regis C.P.; Medeiros, Fatima N.S.; Ushizima, Daniela M.

    2008-09-01T23:59:59.000Z

    This paper introduces a new framework for point target detection in synthetic aperture radar (SAR) images. We focus on the task of locating reflective small regions using alevel set based algorithm. Unlike most of the approaches in image segmentation, we address an algorithm which incorporates speckle statistics instead of empirical parameters and also discards speckle filtering. The curve evolves according to speckle statistics, initially propagating with a maximum upward velocity in homogeneous areas. Our approach is validated by a series of tests on synthetic and real SAR images and compared with three other segmentation algorithms, demonstrating that it configures a novel and efficient method for target detection purpose.

  2. Apport de l'imagerie radar SAR-ERS l'analyse de la gomtrie de la dformation rcente dans les monts Bni Snassen (Maroc) PANGEA No. 45/46 Hassan Tabyaoui et al. June / December 2009

    E-Print Network [OSTI]

    Boyer, Edmond

    monts Béni Snassen (Maroc) PANGEA No. 45/46 Hassan Tabyaoui et al. June / December 2009 18 Apport de l (Maroc nord-oriental) Contribution of the imagery radar SAR-ERS to the analysis of the geometry Modélisation, Equipe Risques Naturels, Aménagement des Territoires et Environnement, BP 1223, Taza-Gare, Maroc

  3. On the accuracy of crosstalk calibration of polarimetric SAR using natural clutter statistics

    SciTech Connect (OSTI)

    Cordey, R.A. (GEC-Marconi Research Centre, Chelmsford (United Kingdom))

    1993-03-01T23:59:59.000Z

    A method for the routine correction of fully polarimetric synthetic aperture radar (SAR) images has been proposed by van Zyl which uses assumed statistical properties of natural distributed targets. The method has the potential to improve dramatically the accuracy of polarimetric imagery contaminated by antenna crosstalk and may be of importance for future spaceborne polarimetric SAR's as well as current airborne systems. The accuracy of the method is assessed here when the statistics of clutter deviate from the assumed form, and limits are placed on likely acceptable deviations. An investigation is presented of these statistics for a heterogeneous forestry and agricultural scene imaged by the NASA/JPL radar. The only significant deviations were found over certain man-made targets, including villages, and a single agricultural field. The results lend support to the routine use of the van Zyl method in such applications.

  4. A New Maximum-Likelihood Change Estimator for Two-Pass SAR Coherent Change Detection.

    SciTech Connect (OSTI)

    Wahl, Daniel E.; Yocky, David A.; Jakowatz, Charles V,

    2014-09-01T23:59:59.000Z

    In this paper, we derive a new optimal change metric to be used in synthetic aperture RADAR (SAR) coherent change detection (CCD). Previous CCD methods tend to produce false alarm states (showing change when there is none) in areas of the image that have a low clutter-to-noise power ratio (CNR). The new estimator does not suffer from this shortcoming. It is a surprisingly simple expression, easy to implement, and is optimal in the maximum-likelihood (ML) sense. The estimator produces very impressive results on the CCD collects that we have tested.

  5. Antarctic Mapping Project ACTIVE RADAR CALIBRATOR

    E-Print Network [OSTI]

    Howat, Ian M.

    RADARSAT Antarctic Mapping Project ACTIVE RADAR CALIBRATOR INSTALLATION DOCUMENT October, 1999 ENVIRONMENTAL RESEARCH INSTITUTE OF MICHIGAN CENTER FOR EARTH SCIENCES ALASKA SAR FACILITY BYRD POLAR RESEARCH...................................................................................................................................................3 Active Radar Calibrator Testing

  6. Iterative Self-Dual Reconstruction on Radar Image Recovery

    SciTech Connect (OSTI)

    Martins, Charles; Medeiros, Fatima; Ushizima, Daniela; Bezerra, Francisco; Marques, Regis; Mascarenhas, Nelson

    2010-05-21T23:59:59.000Z

    Imaging systems as ultrasound, sonar, laser and synthetic aperture radar (SAR) are subjected to speckle noise during image acquisition. Before analyzing these images, it is often necessary to remove the speckle noise using filters. We combine properties of two mathematical morphology filters with speckle statistics to propose a signal-dependent noise filter to multiplicative noise. We describe a multiscale scheme that preserves sharp edges while it smooths homogeneous areas, by combining local statistics with two mathematical morphology filters: the alternating sequential and the self-dual reconstruction algorithms. The experimental results show that the proposed approach is less sensitive to varying window sizes when applied to simulated and real SAR images in comparison with standard filters.

  7. Conventional and synthetic aperature processing for airborne ground penetrating radar

    SciTech Connect (OSTI)

    Cameron, R.M. [Airborne Environmental Surveys, Santa Maria, CA (United States); Simkins, W.L.; Brown, R.D. [MSB Technologies, Inc., Rome, NY (United States)

    1994-12-31T23:59:59.000Z

    For the past four years Airborne Environmental Surveys (AES), a Division of Era Aviation, Inc. has used unique and patented airborne Frequency-Modulated, Continuous Wave (FM-CW) radars and processes for detecting and mapping subsurface phenomena. Primary application has focused on the detection of man-made objects in landfills, hazardous waste sites (some of which contain unexploded ordinance), and subsurface plumes of refined free-floating hydrocarbons. Recently, MSB Technologies, Inc. (MSB) has developed a form of synthetic aperture radar processing (SAR), called GPSAR{trademark}, that is tailored especially for the AES radars. Used as an adjunct to more conventional airborne ground-penetrating radar data processing techniques, GPSAR takes advantage of the radars` coherent transmission and produces imagery that is better focused and more accurate in determining an object`s range and true depth. This paper describes the iterative stages of data processing and analysis used with the radars and shows the added advantages that GPSAR processing offers.

  8. Bistatic SAR: Imagery & Image Products.

    SciTech Connect (OSTI)

    Yocky, David A.; Wahl, Daniel E.; Jakowatz, Charles V,

    2014-10-01T23:59:59.000Z

    While typical SAR imaging employs a co-located (monostatic) RADAR transmitter and receiver, bistatic SAR imaging separates the transmitter and receiver locations. The transmitter and receiver geometry determines if the scattered signal is back scatter, forward scatter, or side scatter. The monostatic SAR image is backscatter. Therefore, depending on the transmitter/receiver collection geometry, the captured imagery may be quite different that that sensed at the monostatic SAR. This document presents imagery and image products formed from captured signals during the validation stage of the bistatic SAR research. Image quality and image characteristics are discussed first. Then image products such as two-color multi-view (2CMV) and coherent change detection (CCD) are presented.

  9. Deployable Synthetic Aperture Radar Reflector

    E-Print Network [OSTI]

    Pellegrino, Sergio

    ) satellite. The structure consists of four cylindrical surfaces formed from thin sheets of carbon-fibre-reinforced-plastic (CFRP) connected by flexible hinges along the edges. The key to forming a cylindrical surface with any. At full scale the reflective surface will be 7.9 m long by 3.2 m wide, and it has been estimated

  10. Final Report (O1-ERD-051) Dynamic InSAR: Imaging Seismic Waves Remotely from Space

    SciTech Connect (OSTI)

    Vincent, P; Rodgers, A; Dodge, D; Zucca, J; Schultz, C; Walter, B; Portnoff, M

    2003-02-07T23:59:59.000Z

    The purpose of this LDRD project was to determine the feasibility of using InSAR (interferometric synthetic aperture radar) to image seismic waves remotely from space. If shown to be feasible, the long-term goal of this project would be to influence future SAR satellite missions and airborne SAR platforms to include a this new capability. This final report summarizes the accomplishments of the originally-planned 2-year project that was cut short to 1 year plus 2 months due to a funding priority change that occurred in the aftermath of the September 11th tragedy. The LDRD-ER project ''Dynamic InSAR: Imaging Seismic Waves from Space'' (01-ERD-051) began in October, (FY01) and ended in December (FY02). Consequently, most of the results and conclusions for this project are represented in the FY0l Annual Report. Nonetheless, additional conclusions and insights regarding the progress of this work are included in this report. In should be noted that this work was restarted and received additional funding under the NA-22 DOE Nonproliferation Program in FY03.

  11. Finding Large Aperture Fractures in Geothermal Resource Areas...

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

    A Three-Component Long-Offset Surface Seismic Survey, PSInSAR, and Kinematic Analysis Finding Large Aperture Fractures in Geothermal Resource Areas Using A Three-Component...

  12. Allan variance computed in space domain: Application to InSAR data to characterize noise and geophysical signal

    E-Print Network [OSTI]

    Cavalié, Olivier

    2015-01-01T23:59:59.000Z

    The Allan variance was introduced fifty years ago for analyzing the stability of frequency standards. Beside its metrological interest, it is also an estimator of the large trends of the power spectral density (PSD) of frequency deviation. For instance, the Allan variance is able to discriminate different types of noise characterized by different power laws in the PSD. But, it was also used in other fields: accelerometry, geophysics, geodesy, astrophysics and even finances! However, it seems that up to now, it has been exclusively applied for time series analysis. We propose here to use the Allan variance onto spatial data. Interferometric synthetic aperture radar (InSAR) is used in geophysics to image ground displacements in space (over the SAR image spatial coverage) and in time thank to the regular SAR image acquisitions by dedicated satellites. The main limitation of the technique is the atmospheric disturbances that affect the radar signal while traveling from the sensor to the ground and back. In this p...

  13. Design of dual frequency interferometric SAR

    SciTech Connect (OSTI)

    Kim, Y.; Edelstein, W.; Caro, E. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States)

    1996-03-01T23:59:59.000Z

    Using a spaceborne interferometric SAR, it is possible to produce a high resolution global topographic map with a height accuracy of several meters. However, frequency selection of the interferometric SAR is rather complicated due to interferometric phenomenology and atmospheric effects. In this paper, we propose a dual frequency interferometric SAR to achieve better understanding of interferometric height (especially for penetrable medium) and corresponding calibration and to remove the atmospheric effects. The selected frequencies are L- and Ku- bands. We also present a radar design and show that a light weight and efficient SAR can be designed using new technologies and dual frequency advantages even with two frequency radars in a single spacecraft. {copyright} {ital 1996 American Institute of Physics.}

  14. Radar polarimetry for geoscience applications

    SciTech Connect (OSTI)

    Elachi, C.; Kuga, Y.; McDonald, K.; Sarabandi, K.; Ulaby, F.T.; Whitt, M.; Zebker, H.; van Zyl, J.J.

    1990-01-01T23:59:59.000Z

    A source book for remote sensing and radar design engineers, this text covers wave polarization, polarization synthesis, scattering matrices, SAR polarization systems, and an array of applications It covers: an introduction to the different mathematical representations used to describe scattering properties, a review of scatterometer system design and calibration techniques for use in polarimetric measurements, a study of specific polarimetric radar systems, such as the shuttle imaging radar C (SIR-C), that includes calibration and compression techniques, data processing guidelines, and design approaches.

  15. Final Report: Detection and Characterization of Underground Facilities by Stochastic Inversion and Modeling of Data from the New Generation of Synthetic Aperture Satellites

    SciTech Connect (OSTI)

    Foxall, W; Cunningham, C; Mellors, R; Templeton, D; Dyer, K; White, J

    2012-02-27T23:59:59.000Z

    Many clandestine development and production activities can be conducted underground to evade surveillance. The purpose of the study reported here was to develop a technique to detect underground facilities by broad-area search and then to characterize the facilities by inversion of the collected data. This would enable constraints to be placed on the types of activities that would be feasible at each underground site, providing a basis the design of targeted surveillance and analysis for more complete characterization. Excavation of underground cavities causes deformation in the host material and overburden that produces displacements at the ground surface. Such displacements are often measurable by a variety of surveying or geodetic techniques. One measurement technique, Interferometric Synthetic Aperture Radar (InSAR), uses data from satellite-borne (or airborne) synthetic aperture radars (SARs) and so is ideal for detecting and measuring surface displacements in denied access regions. Depending on the radar frequency and the acquisition mode and the surface conditions, displacement maps derived from SAR interferograms can provide millimeter- to centimeter-level measurement accuracy on regional and local scales at spatial resolution of {approx}1-10 m. Relatively low-resolution ({approx}20 m, say) maps covering large regions can be used for broad-area detection, while finer resolutions ({approx}1 m) can be used to image details of displacement fields over targeted small areas. Surface displacements are generally expected to be largest during or a relatively short time after active excavation, but, depending on the material properties, measurable displacement may continue at a decreasing rate for a considerable time after completion. For a given excavated volume in a given geological setting, the amplitude of the surface displacements decreases as the depth of excavation increases, while the area of the discernable displacement pattern increases. Therefore, the ability to detect evidence for an underground facility using InSAR depends on the displacement sensitivity and spatial resolution of the interferogram, as well as on the size and depth of the facility and the time since its completion. The methodology development described in this report focuses on the exploitation of synthetic aperture radar data that are available commercially from a number of satellite missions. Development of the method involves three components: (1) Evaluation of the capability of InSAR to detect and characterize underground facilities ; (2) inversion of InSAR data to infer the location, depth, shape and volume of a subsurface facility; and (3) evaluation and selection of suitable geomechanical forward models to use in the inversion. We adapted LLNL's general-purpose Bayesian Markov Chain-Monte Carlo procedure, the 'Stochastic Engine' (SE), to carry out inversions to characterize subsurface void geometries. The SE performs forward simulations for a large number of trial source models to identify the set of models that are consistent with the observations and prior constraints. The inverse solution produced by this kind of stochastic method is a posterior probability density function (pdf) over alternative models, which forms an appropriate input to risk-based decision analyses to evaluate subsequent response strategies. One major advantage of a stochastic inversion approach is its ability to deal with complex, non-linear forward models employing empirical, analytical or numerical methods. However, while a geomechanical model must incorporate adequate physics to enable sufficiently accurate prediction of surface displacements, it must also be computationally fast enough to render the large number of forward realizations needed in stochastic inversion feasible. This latter requirement prompted us first to investigate computationally efficient empirical relations and closed-form analytical solutions. However, our evaluation revealed severe limitations in the ability of existing empirical and analytical forms to predict deformations from undergro

  16. Analysis, comparison, and modeling of radar interferometry, date of surface deformation signals associated with underground explosions, mine collapses and earthquakes. Phase I: underground explosions, Nevada Test Site

    SciTech Connect (OSTI)

    Foxall, W; Vincent, P; Walter, W

    1999-07-23T23:59:59.000Z

    We have previously presented simple elastic deformation modeling results for three classes of seismic events of concern in monitoring the CTBT--underground explosions, mine collapses and earthquakes. Those results explored the theoretical detectability of each event type using synthetic aperture radar interferometry (InSAR) based on commercially available satellite data. In those studies we identified and compared the characteristics of synthetic interferograms that distinguish each event type, as well the ability of the interferograms to constrain source parameters. These idealized modeling results, together with preliminary analysis of InSAR data for the 1995 mb 5.2 Solvay mine collapse in southwestern Wyoming, suggested that InSAR data used in conjunction with regional seismic monitoring holds great potential for CTBT discrimination and seismic source analysis, as well as providing accurate ground truth parameters for regional calibration events. In this paper we further examine the detectability and ''discriminating'' power of InSAR by presenting results from InSAR data processing, analysis and modeling of the surface deformation signals associated with underground explosions. Specifically, we present results of a detailed study of coseismic and postseismic surface deformation signals associated with underground nuclear and chemical explosion tests at the Nevada Test Site (NTS). Several interferograms were formed from raw ERS-1/2 radar data covering different time spans and epochs beginning just prior to the last U.S. nuclear tests in 1992 and ending in 1996. These interferograms have yielded information about the nature and duration of the source processes that produced the surface deformations associated with these events. A critical result of this study is that significant post-event surface deformation associated with underground nuclear explosions detonated at depths in excess of 600 meters can be detected using differential radar interferometry. An immediate implication of this finding is that underground nuclear explosions may not need to be captured coseismically by radar images acquired before and after an event in order to be detectable. This has obvious advantages in CTBT monitoring since suspect seismic events--which usually can be located within a 100 km by 100 km area of an ERS-1/2 satellite frame by established seismic methods-can be imaged after the event has been identified and located by existing regional seismic networks. Key Words: InSAR, SLC images, interferogram, synthetic interferogram, ERS-1/2 frame, phase unwrapping, DEM, coseismic, postseismic, source parameters.

  17. Digital Intermediate Frequency Receiver Module For Use In Airborne Sar Applications

    DOE Patents [OSTI]

    Tise, Bertice L. (Albuquerque, NM); Dubbert, Dale F. (Cedar Crest, NM)

    2005-03-08T23:59:59.000Z

    A digital IF receiver (DRX) module directly compatible with advanced radar systems such as synthetic aperture radar (SAR) systems. The DRX can combine a 1 G-Sample/sec 8-bit ADC with high-speed digital signal processor, such as high gate-count FPGA technology or ASICs to realize a wideband IF receiver. DSP operations implemented in the DRX can include quadrature demodulation and multi-rate, variable-bandwidth IF filtering. Pulse-to-pulse (Doppler domain) filtering can also be implemented in the form of a presummer (accumulator) and an azimuth prefilter. An out of band noise source can be employed to provide a dither signal to the ADC, and later be removed by digital signal processing. Both the range and Doppler domain filtering operations can be implemented using a unique pane architecture which allows on-the-fly selection of the filter decimation factor, and hence, the filter bandwidth. The DRX module can include a standard VME-64 interface for control, status, and programming. An interface can provide phase history data to the real-time image formation processors. A third front-panel data port (FPDP) interface can send wide bandwidth, raw phase histories to a real-time phase history recorder for ground processing.

  18. Relating forest biomass to SAR data

    SciTech Connect (OSTI)

    LeToan, T.; Beaudoin, A. (Centre d'Etude Spatiale des Rayonnements CNRS- Univ. Paul Sabatier Toulouse (FR)); Riom, J.; Guyon, D. (Lab. de Bioclimatologie INRA, Bordeaux (FR))

    1992-03-01T23:59:59.000Z

    This paper presents the results of an experiment defined to demonstrate the use of radar to retrieve forest biomass. The SAR data, after calibration, has been analyzed together with ground data collected on forest stands from young stage (8 yrs) to nature stage (46 yrs). The dynamic range of the radar backscatter intensity from forest was found maximum at P-band and decreases with increasing frequencies. Also, cross-polarized backscatter intensity yields the best sensitivities to variations of forest biomass. L-band data confirmed past results on good correlation with forest parameters. The most striking observation has been the strong correlation of P-band backscatter intensity to forest biomass. In order to develop algorithms to infer forest biomass from spaceborne SAR's, the experimental results will be compared with observations on other forest ecosystems and will be interpreted by theoretical modeling.

  19. Land subsidence in the Cerro Prieto Geothermal Field, 1 Baja California, Mexico, from 1994 to 2005. An integrated analysis of DInSAR, levelingand geological data.

    SciTech Connect (OSTI)

    Sarychikhina, O; Glowacka, E; Mellors, R; Vidal, F S

    2011-03-03T23:59:59.000Z

    Cerro Prieto is the oldest and largest Mexican geothermal field in operation and has been producing electricity since 1973. The large amount of geothermal fluids extracted to supply steam to the power plants has resulted in considerable deformation in and around the field. The deformation includes land subsidence and related ground fissuring and faulting. These phenomena have produced severe damages to infrastructure such as roads, irrigation canals and other facilities. In this paper, the technique of Differential Synthetic Aperture Radar Interferometry (DInSAR) is applied using C-band ENVISAR ASAR data acquired between 2003 and 2006 to determine the extent and amount of land subsidence in the Mexicali Valley near Cerro Prieto Geothermal Field. The DInSAR results were compared with published data from precise leveling surveys (1994- 1997 and 1997-2006) and detailed geological information in order to improve the understanding of temporal and spatial distributions of anthropogenic subsidence in the Mexicali Valley. The leveling and DInSAR data were modeled to characterize the observed deformation in terms of fluid extraction. The results confirm that the tectonic faults control the spatial extent of the observed subsidence. These faults likely act as groundwater flow barriers for aquifers and reservoirs. The shape of the subsiding area coincides with the Cerro Prieto pull-apart basin. In addition, the spatial pattern of the subsidence as well as changes in rate are highly correlated with the development of the Cerro Prieto Geothermal Field.

  20. Through-the-wall Imaging Radar Students: Thang Bui and Joseph Rabig

    E-Print Network [OSTI]

    Ghahramani, Zoubin

    radar (SAR) to image objects behind a wall, using a pair of horn antennas and a vector network analyser was used to calibrate out unknown cable and system delays · Objects are resolved at correct locations close to the SAR Focusing delay geometry Theory ­ Image Processing Electromagnetic distance between horn

  1. Rotating Aperture System

    DOE Patents [OSTI]

    Rusnak, Brian (Livermore, CA); Hall, James M. (Livermore, CA); Shen, Stewart (Danville, CA); Wood, Richard L. (Santa Fe, NM)

    2005-01-18T23:59:59.000Z

    A rotating aperture system includes a low-pressure vacuum pumping stage with apertures for passage of a deuterium beam. A stator assembly includes holes for passage of the beam. The rotor assembly includes a shaft connected to a deuterium gas cell or a crossflow venturi that has a single aperture on each side that together align with holes every rotation. The rotating apertures are synchronized with the firing of the deuterium beam such that the beam fires through a clear aperture and passes into the Xe gas beam stop. Portions of the rotor are lapped into the stator to improve the sealing surfaces, to prevent rapid escape of the deuterium gas from the gas cell.

  2. A 1.56THz compact radar range for W-band imagery of scale-model tactical targets

    E-Print Network [OSTI]

    Massachusetts at Lowell, University of

    . The data needed for these programs include high range resolution (HRR) and synthetic aperture images (SAR has been assembled in a very stable, air-conditioned laboratory. Measurements taken on a calibration

  3. Variable-aperture screen

    DOE Patents [OSTI]

    Savage, G.M.

    1991-10-29T23:59:59.000Z

    Apparatus is described for separating material into first and second portions according to size including a plurality of shafts, a plurality of spaced disks radiating outwardly from each of the shafts to define apertures and linkage interconnecting the shafts for moving the shafts toward or away from one another to vary the size of the apertures while the apparatus is performing the separating function. 10 figures.

  4. Confocal coded aperture imaging

    DOE Patents [OSTI]

    Tobin, Jr., Kenneth William (Harriman, TN); Thomas, Jr., Clarence E. (Knoxville, TN)

    2001-01-01T23:59:59.000Z

    A method for imaging a target volume comprises the steps of: radiating a small bandwidth of energy toward the target volume; focusing the small bandwidth of energy into a beam; moving the target volume through a plurality of positions within the focused beam; collecting a beam of energy scattered from the target volume with a non-diffractive confocal coded aperture; generating a shadow image of said aperture from every point source of radiation in the target volume; and, reconstructing the shadow image into a 3-dimensional image of the every point source by mathematically correlating the shadow image with a digital or analog version of the coded aperture. The method can comprise the step of collecting the beam of energy scattered from the target volume with a Fresnel zone plate.

  5. Satellite SAR Remote Sensing of Great Lakes Ice Cover, Part 2. Ice Classification and Mapping

    E-Print Network [OSTI]

    Satellite SAR Remote Sensing of Great Lakes Ice Cover, Part 2. Ice Classification and Mapping° to 60° for all polarizations, was processed to radar cross-section to establish a library of signatures (look-up table) for different ice types. The library is used in the computer classifica- tion

  6. Aperture center energy showcase

    SciTech Connect (OSTI)

    Torres, J. J.

    2012-03-01T23:59:59.000Z

    Sandia and Forest City have established a Cooperative Research and Development Agreement (CRADA), and the partnership provides a unique opportunity to take technology research and development from demonstration to application in a sustainable community. A project under that CRADA, Aperture Center Energy Showcase, offers a means to develop exhibits and demonstrations that present feedback to community members, Sandia customers, and visitors. The technologies included in the showcase focus on renewable energy and its efficiency, and resilience. These technologies are generally scalable, and provide secure, efficient solutions to energy production, delivery, and usage. In addition to establishing an Energy Showcase, support offices and conference capabilities that facilitate research, collaboration, and demonstration were created. The Aperture Center project focuses on establishing a location that provides outreach, awareness, and demonstration of research findings, emerging technologies, and project developments to Sandia customers, visitors, and Mesa del Sol community members.

  7. Ultra-wideband VHF SAR -- Design and measurements

    SciTech Connect (OSTI)

    Hellsten, H.; Froelind, P.O.; Gustavsson, A.; Jonsson, T.; Larsson, B.; Stenstroem, G. [National Defense Research Establishment, Linkoeping (Sweden); Binder, B.T.; Mirkin, M.; Ayasli, S. [Massachusetts Inst. of Technology, Lexington, MA (United States)

    1994-12-31T23:59:59.000Z

    CARABAS, an acronym for ``Coherent All Radio Band Sensing``, is an airborne, horizontal-polarization SAR operating across the frequency band 20--90 MHz, conceived, designed and built by FOA in Sweden. The original motivation for designing such a low frequency system was that a large relative or fractional bandwidth could be achieved at low frequencies. For reasons to be explained, a large fractional bandwidth was considered to be of potential benefit for radar detection in severe clutter environments. A feasibility study of a short wave ultra-wideband radar started at FOA in 1985. Actual construction of the CARABAS system commenced 1987, aircraft integration took place during 1991 and the first radar tests were conducted in early 1992. From the fall of 1992 onwards, field campaigns and evaluation studies have been conducted as a joint effort between FOA and MIT Lincoln Laboratory in the US. This article will focus on experiences concerning foliage penetration with the system. First the authors touch upon the CARABAS system characteristics, outline the arguments behind a large-fractional-bandwidth VHF-band SAR approach to foliage penetration, and finally present some early experimental results. The authors refer to other papers, for a fuller explanation of the system, for more details of image calibration and for results concerning underground imaging.

  8. Automatic signal processing of front monitor radar for tunneling machines

    SciTech Connect (OSTI)

    Sato, Toru [Kyoto Univ. (Japan). Dept. of Electronics and Communication] [Kyoto Univ. (Japan). Dept. of Electronics and Communication; Takeda, Kenya [NTT Co. Ltd., Chiba (Japan)] [NTT Co. Ltd., Chiba (Japan); Nagamatsu, Takashi [Mitsubishi Heavy Industries, Ltd., Tokyo (Japan)] [Mitsubishi Heavy Industries, Ltd., Tokyo (Japan); Wakayama, Toshio [Mitsubishi Electric Corp., Kamakura, Kanagawa (Japan)] [Mitsubishi Electric Corp., Kamakura, Kanagawa (Japan); Kimura, Iwane [Osaka Inst. of Tech., Hirakata, Osaka (Japan)] [Osaka Inst. of Tech., Hirakata, Osaka (Japan); Shinbo, Tetsuya [Komatsu Co. Ltd., Kanagawa (Japan)] [Komatsu Co. Ltd., Kanagawa (Japan)

    1997-03-01T23:59:59.000Z

    It is planned to install a front monitoring impulse radar on the surface of the rotating drill of tunneling machines in order to detect obstacles such as casing pipes of vertical borings. The conventional aperture synthesis technique can no more be applied to such cases because the radar image of a pipe dies not constituent a hyperbola as is the case for linear scanning radars. The authors have developed a special purpose signal processing algorithm with the aid of the discrete model fitting method, which can be used for any pattern of scanning. The details of the algorithm are presented together with the results of numerical simulations and test site experiments.

  9. Name of Module: Optical Remote Sensing

    E-Print Network [OSTI]

    Wichmann, Felix

    calibration, pre-processing of satellite images, arithmetic image operations, principal axis transform, image textures, microwave systems, radar with synthetic aperture (SAR) 3. Module Components Course Name

  10. Hydrol. Earth Syst. Sci., 11, 739752, 2007 www.hydrol-earth-syst-sci.net/11/739/2007/

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    set approach to calibrating distributed flood inundation models using remote sensing observations F inundation maps. Conditioning of the inun- dation maps on fuzzified Synthetic Aperture Radar (SAR) images

  11. John L. LaBrecque is Lead of the Earth Surface and Interior Focus Area within NASA's Science Mission Directorate. Dr. LaBrecque's responsibilities include the development

    E-Print Network [OSTI]

    Wang, Yuqing

    NI-SAR synthetic aperture radar mission. These missions address a broad scope of scientific, and satellites. Among his achievements were scientific collaborations resulting in the calibration

  12. Interseismic deformation and creep along the central section of the North Anatolian Fault (Turkey): InSAR observations

    E-Print Network [OSTI]

    Fialko, Yuri

    Interseismic deformation and creep along the central section of the North Anatolian Fault (Turkey the central section of the North Anatolian Fault (NAF) in Turkey using interferometric synthetic aperture along the central section of the North Anatolian Fault (Turkey): InSAR observations and implications

  13. Feasibility study for mapping the polar ice bottom topography using interferometric synthetic-aperture

    E-Print Network [OSTI]

    Kansas, University of

    interferometric synthetic-aperture radar processing for basal surface topography mapping of the thickest GreenlandFeasibility study for mapping the polar ice bottom topography using interferometric synthetic sheets. Ice bottom topography drives ice dynamics, which affects the mass balance. Accurate information

  14. Radar signal pre-processing to suppress surface bounce and multipath

    DOE Patents [OSTI]

    Paglieroni, David W; Mast, Jeffrey E; Beer, N. Reginald

    2013-12-31T23:59:59.000Z

    A method and system for detecting the presence of subsurface objects within a medium is provided. In some embodiments, the imaging and detection system operates in a multistatic mode to collect radar return signals generated by an array of transceiver antenna pairs that is positioned across the surface and that travels down the surface. The imaging and detection system pre-processes that return signal to suppress certain undesirable effects. The imaging and detection system then generates synthetic aperture radar images from real aperture radar images generated from the pre-processed return signal. The imaging and detection system then post-processes the synthetic aperture radar images to improve detection of subsurface objects. The imaging and detection system identifies peaks in the energy levels of the post-processed image frame, which indicates the presence of a subsurface object.

  15. aperture radar 3d: Topics by E-print Network

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

    study was performed to understand the correlation between printing parameters in the FDM 3D printing process, and the force required to remove a part from the build platform of a...

  16. Passive Synthetic Aperture Radar Imaging of Ground Moving Targets

    E-Print Network [OSTI]

    Yazici, Birsen

    of opportunity such as radio, cell phone, and television transmission towers. The absence of active signal towers. We describe a novel forward model and a corresponding filtered-backprojection type image

  17. aperture radar image: Topics by E-print Network

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

    Engineering Websites Summary: ) satellite. The structure consists of four cylindrical surfaces formed from thin sheets of carbon-fibre-reinforced-plastic (CFRP) connected by...

  18. Inversion of synthetic aperture radar interferograms for sources of

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation, searchOf Kilauea Volcano, Hawaii | Open EnergyIGPIntevac JumpInvener

  19. Because ScanSAR images have a different scale and orientation

    E-Print Network [OSTI]

    deforestation by synthetic aperture radar Martin Whittle(a), Shaun Quegan(a),Kokok Yulianto(b) and Yumiko Uryu. The difference is an estimate of interim deforestation. The FBD scene used here fully overlaps both databases. Eva, et al. (2002). "Determination of Deforestation Rates of the World's Humid Tropical Forests

  20. Radar cross section of triangular trihedral reflector with extended bottom plate.

    SciTech Connect (OSTI)

    Brock, Billy C.; Doerry, Armin Walter

    2009-05-01T23:59:59.000Z

    Trihedral corner reflectors are the preferred canonical target for SAR performance evaluation for many radar development programs. The conventional trihedrals have problems with substantially reduced Radar Cross Section (RCS) at low grazing angles, unless they are tilted forward, but in which case other problems arise. Consequently there is a need for better low grazing angle performance for trihedrals. This is facilitated by extending the bottom plate. A relevant analysis of RCS for an infinite ground plate is presented. Practical aspects are also discussed.

  1. Segmentacion de imagenes SAR usando Level Sets y Competicion de Regiones bajo el modelo GH

    E-Print Network [OSTI]

    Figueira, Santiago

    Segmentaci´on de im´agenes SAR usando Level Sets y Competici´on de Regiones bajo el modelo GH Mar Ciencias Exactas y Naturales, Universidad de Buenos Aires Resumen Las im´agenes de Radar de Apertura Sint speckle, a diferencia del ruido de im´agenes ´opticas, no es gaussiano, ni tampoco es aditivo sino que es

  2. Sparse aperture endoscope

    DOE Patents [OSTI]

    Fitch, Joseph P. (Livermore, CA)

    1999-07-06T23:59:59.000Z

    An endoscope which reduces the volume needed by the imaging part thereof, maintains resolution of a wide diameter optical system, while increasing tool access, and allows stereographic or interferometric processing for depth and perspective information/visualization. Because the endoscope decreases the volume consumed by imaging optics such allows a larger fraction of the volume to be used for non-imaging tools, which allows smaller incisions in surgical and diagnostic medical applications thus produces less trauma to the patient or allows access to smaller volumes than is possible with larger instruments. The endoscope utilizes fiber optic light pipes in an outer layer for illumination, a multi-pupil imaging system in an inner annulus, and an access channel for other tools in the center. The endoscope is amenable to implementation as a flexible scope, and thus increases the utility thereof. Because the endoscope uses a multi-aperture pupil, it can also be utilized as an optical array, allowing stereographic and interferometric processing.

  3. Sparse aperture endoscope

    DOE Patents [OSTI]

    Fitch, J.P.

    1999-07-06T23:59:59.000Z

    An endoscope is disclosed which reduces the volume needed by the imaging part, maintains resolution of a wide diameter optical system, while increasing tool access, and allows stereographic or interferometric processing for depth and perspective information/visualization. Because the endoscope decreases the volume consumed by imaging optics such allows a larger fraction of the volume to be used for non-imaging tools, which allows smaller incisions in surgical and diagnostic medical applications thus produces less trauma to the patient or allows access to smaller volumes than is possible with larger instruments. The endoscope utilizes fiber optic light pipes in an outer layer for illumination, a multi-pupil imaging system in an inner annulus, and an access channel for other tools in the center. The endoscope is amenable to implementation as a flexible scope, and thus increases it's utility. Because the endoscope uses a multi-aperture pupil, it can also be utilized as an optical array, allowing stereographic and interferometric processing. 7 figs.

  4. Large aperture optical switching devices

    SciTech Connect (OSTI)

    Goldhar, J.; Henesian, M.A.

    1983-12-12T23:59:59.000Z

    We have developed a new approach to constructing large aperture optical switches for next generation inertial confinement fusion lasers. A transparent plasma electrode formed in low pressure ionized gas acts as a conductive coating to allow the uniform charging of the optical faces of an electro-optic material. In this manner large electric fields can be applied longitudinally to large aperture, high aspect ratio Pockels cells. We propose a four-electrode geometry to create the necessary high conductivity plasma sheets, and have demonstrated fast (less than 10 nsec) switching in a 5x5 cm aperture KD*P Pockels cell with such a design. Detaid modelling of Pockels cell performance with plasma electrodes has been carried out for 15 and 30 cm aperture designs.

  5. OVERBURDEN PRESSURE AFFECTS FRACTURE APERTURE

    E-Print Network [OSTI]

    Schechter, David S.

    OVERBURDEN PRESSURE AFFECTS FRACTURE APERTURE AND FRACTURE PERMEABILITY IN A FRACTURED RESERVOIR are in integrated reservoir study, reservoir charac- terization, naturally fractured reservoirs, waterflooding in Hydraulically and Naturally Fractured Reservoirs." His research areas include experimental analysis

  6. ASAP progress and expenditure report for the month of December 1--31, 1995. Joint UK/US radar program

    SciTech Connect (OSTI)

    Twogood, R.E.; Brase, J.M.; Chambers, D.H.; Mantrom, D.D.; Miller, M.G.; Newman, M.J.; Robey, H.F.; Vigars, M.L.

    1996-01-19T23:59:59.000Z

    The RAR/SAR is a high-priority radar system for the joint US/UK Program. Based on previous experiment results and coordination with the UK, specifications needed for future radar experiments were identified as follows: dual polarimetric (HH and VV) with medium to high resolution in SAR mode. Secondary airborne installation requirements included; high power (circa 10kw) and SLIER capability to emulate Tupelev-134 type system; initially x-band but easily extendible to other frequencies. In FY96 we intended to enhance the radar system`s capabilities by providing a second polarization (VV), spotlight imaging mode, extended frequency of operation to include S- band, increase power, and interface to an existing infrared sensor. Short term objectives are: continue to evaluate and characterize the radar system; upgrade navigation and real-time processing capability to refine motion compensation; upgrade to dual polarimetry (add VV); and develop a ``spotlight`` mode capability. Accomplishments this reporting period: design specifications for the SAR system polarimetric upgrade are complete. The upgrade is ready to begin the procurement cycle when funds become available. System characterization is one of the highest priority tasks for the SAR. Although the radar is dedicated for our use, Hughes is waiting for contract funding before allowing us access to the hardware

  7. Methods And System Suppressing Clutter In A Gain-Block, Radar-Responsive Tag System

    DOE Patents [OSTI]

    Ormesher, Richard C. (Albuquerque, NM); Axline, Robert M. (Albuquerque, NM)

    2006-04-18T23:59:59.000Z

    Methods and systems reduce clutter interference in a radar-responsive tag system. A radar transmits a series of linear-frequency-modulated pulses and receives echo pulses from nearby terrain and from radar-responsive tags that may be in the imaged scene. Tags in the vicinity of the radar are activated by the radar's pulses. The tags receive and remodulate the radar pulses. Tag processing reverses the direction, in time, of the received waveform's linear frequency modulation. The tag retransmits the remodulated pulses. The radar uses a reversed-chirp de-ramp pulse to process the tag's echo. The invention applies to radar systems compatible with coherent gain-block tags. The invention provides a marked reduction in the strength of residual clutter echoes on each and every echo pulse received by the radar. SAR receiver processing effectively whitens passive-clutter signatures across the range dimension. Clutter suppression of approximately 14 dB is achievable for a typical radar system.

  8. Large aperture diffractive space telescope

    DOE Patents [OSTI]

    Hyde, Roderick A. (Livermore, CA)

    2001-01-01T23:59:59.000Z

    A large (10's of meters) aperture space telescope including two separate spacecraft--an optical primary objective lens functioning as a magnifying glass and an optical secondary functioning as an eyepiece. The spacecraft are spaced up to several kilometers apart with the eyepiece directly behind the magnifying glass "aiming" at an intended target with their relative orientation determining the optical axis of the telescope and hence the targets being observed. The objective lens includes a very large-aperture, very-thin-membrane, diffractive lens, e.g., a Fresnel lens, which intercepts incoming light over its full aperture and focuses it towards the eyepiece. The eyepiece has a much smaller, meter-scale aperture and is designed to move along the focal surface of the objective lens, gathering up the incoming light and converting it to high quality images. The positions of the two space craft are controlled both to maintain a good optical focus and to point at desired targets which may be either earth bound or celestial.

  9. IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 48, NO. 9, SEPTEMBER 2010 3521 An End-to-End Error Model for Classification

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    and for the development of robust classification methods using existing SAR instruments. Index Terms--Calibration, image-to-End Error Model for Classification Methods Based on Temporal Change or Polarization Ratio of SAR Intensities a synthetic aperture radar (SAR) intensity ratio as a classification feature. The two SAR intensities involved

  10. A Forward-Looking High-Resolution GPR System Joel Kositsky,*

    E-Print Network [OSTI]

    Milanfar, Peyman

    on automatic target detection will be presented. Keywords: GPR, radar, landmine, clutter, mobile, SAR, mine-frequency, synthetic aperture radar (SAR) approach was chosen as being the most appropriate and versatile radar for the production of a flat, wideband spectrum, ease in signal processing and system calibration, and ease

  11. WFPC2 aperture photometry and PSF modelling

    E-Print Network [OSTI]

    N. R. Tanvir; D. R. T. Robinson; T. von Hippel

    1995-03-22T23:59:59.000Z

    Since the WFPC-2 undersamples the PSF, aperture photometry can produce results which are competetive with profile fitting in many situations. This article reports and investigation of aperture corrections using both real data and PSF models.

  12. Micropower impulse radar technology and applications

    SciTech Connect (OSTI)

    Mast, J., LLNL

    1998-04-15T23:59:59.000Z

    The LLNL-developed Micropower Impulse Radar (MIR) technology has quickly gone from laboratory concept to embedded circuitry in numerous government and commercial systems in the last few years[l]. The main ideas behind MIR, invented by T. McEwan in the Laser Program, are the generation and detection systems for extremely low- power ultra-wideband pulses in the gigaHertz regime using low-cost components. These ideas, coupled with new antenna systems, timing and radio-frequency (RF) circuitry, computer interfaces, and signal processing, have provided the catalyst for a new generation of compact radar systems. Over the past several years we have concentrated on a number of applications of MIR which address a number of remote-sensing applications relevant to emerging programs in defense, transportation, medical, and environmental research. Some of the past commercial successes have been widely publicized [2] and are only now starting to become available for market. Over 30 patents have been filed and over 15 licenses have been signed on various aspects of the MIR technology. In addition, higher performance systems are under development for specific laboratory programs and government reimbursables. The MIR is an ultra- wideband, range-gated radar system that provides the enabling hardware technology used in the research areas mentioned above. It has numerous performance parameters that can be Selected by careful design to fit the requirements. We have improved the baseline, short- range, MIR system to demonstrate its effectiveness. The radar operates over the hand from approximately I to 4 GHz with pulse repetition frequencies up to 10 MHz. It provides a potential range resolution of I cm at ranges of greater than 20 m. We have developed a suite of algorithms for using MIR for image formation. These algorithms currently support Synthetic aperture and multistate array geometries. This baseline MIR radar imaging system has been used for several programmatic applications.

  13. Access Control for SAR Systems Stephen Quirolgico

    E-Print Network [OSTI]

    Access Control for SAR Systems Stephen Quirolgico Vincent Hu Tom Karygiannis NIST IR 7815 #12;NIST Systems Stephen Quirolgico Vincent Hu Tom Karygiannis Computer Security Division Information Technology

  14. Interferometric SAR phase difference calibration: Methods and results

    SciTech Connect (OSTI)

    Bickel, D.L.; Hensley, W.H.

    1993-12-31T23:59:59.000Z

    This paper addresses the steps necessary to determine and maintain the phase calibration of a two-channel interferometric synthetic aperture radar (IFSAR). The method, setup, and accuracy of four different calibration techniques are compared. The most novel technique involves pointing the interferometric baseline at nadir and imaging a lake surface. The other techniques include measuring various flat surfaces in traditional side-looking IFSAR maps, in-flight closed-loop calibration path measurements, and static laboratory measurements. Initial results indicate that, using combinations of these measurements, it is possible to maintain the interferometric phase calibration of Sandia National Laboratories` K{sub U} Band IFSAR to better than 3 degrees. The time variability of various parts of the calibration and requirements for recalibration are also discussed.

  15. The Large Aperture GRB Observatory

    E-Print Network [OSTI]

    Allard, D; Asorey, H; Barros, H; Bertou, X; Castillo, M; Chirinos, J M; De Castro, A; Flores, S; González, J; Berisso, M Gomez; Grajales, J; Guada, C; Day, W R Guevara; Ishitsuka, J; López, J A; Martínez, O; Melfo, A; Meza, E; Loza, P Miranda; Barbosa, E Moreno; Murrugarra, C; Núñez, L A; Ormachea, L J Otiniano; Pérez, G; Perez, Y; Ponce, E; Quispe, J; Quintero, C; Rivera, H; Rosales, M; Rovero, A C; Saavedra, O; Salazar, H; Tello, J C; Peralda, R Ticona; Varela, E; Velarde, A; Villaseñor, L; Wahl, D; Zamalloa, M A

    2009-01-01T23:59:59.000Z

    The Large Aperture GRB Observatory (LAGO) is aiming at the detection of the high energy (around 100 GeV) component of Gamma Ray Bursts, using the single particle technique in arrays of Water Cherenkov Detectors (WCD) in high mountain sites (Chacaltaya, Bolivia, 5300 m a.s.l., Pico Espejo, Venezuela, 4750 m a.s.l., Sierra Negra, Mexico, 4650 m a.s.l). WCD at high altitude offer a unique possibility of detecting low gamma fluxes in the 10 GeV - 1 TeV range. The status of the Observatory and data collected from 2007 to date will be presented.

  16. Ion mobility spectrometer with virtual aperture grid

    DOE Patents [OSTI]

    Pfeifer, Kent B. (Los Lunas, NM); Rumpf, Arthur N. (Albuquerque, NM)

    2010-11-23T23:59:59.000Z

    An ion mobility spectrometer does not require a physical aperture grid to prevent premature ion detector response. The last electrodes adjacent to the ion collector (typically the last four or five) have an electrode pitch that is less than the width of the ion swarm and each of the adjacent electrodes is connected to a source of free charge, thereby providing a virtual aperture grid at the end of the drift region that shields the ion collector from the mirror current of the approaching ion swarm. The virtual aperture grid is less complex in assembly and function and is less sensitive to vibrations than the physical aperture grid.

  17. Ris National Laboratory Satellite SAR applied in offshore wind

    E-Print Network [OSTI]

    Risø National Laboratory Satellite SAR applied in offshore wind ressource mapping: possibilities is to quantify the regional offshore wind climate for wind energy application based on satellite SAR ·Study of 85SAR(m/s) Hasager, Dellwik, Nielsen and Furevik, 2004, Validation of ERS-2 SAR offshore wind-speed maps

  18. Sandia National Laboratories: Radar Friendly Blades

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

    MitigationRadar Friendly Blades Radar Friendly Blades Some wind farms have the potential to cause interference with the normal operation of radar systems used for security, weather...

  19. Solar Central Receiver with an Irising Aperture

    E-Print Network [OSTI]

    Galal, T.; Kulaib, A. M.; Abuzaid, M.

    2010-01-01T23:59:59.000Z

    . If the aperture is small, it will be inefficient for periods when the solar isolation is inclined due to spillage. However, if the aperture is large, it will be inefficient for periods when the solar isolation is normal, due to excess heat radiation and convection...

  20. Solar Central Receiver with an Irising Aperture 

    E-Print Network [OSTI]

    Galal, T.; Kulaib, A. M.; Abuzaid, M.

    2010-01-01T23:59:59.000Z

    . If the aperture is small, it will be inefficient for periods when the solar isolation is inclined due to spillage. However, if the aperture is large, it will be inefficient for periods when the solar isolation is normal, due to excess heat radiation and convection...

  1. Measurement of the human sar a)

    E-Print Network [OSTI]

    Allen, Jont

    Measurement of the human sar a) acoustic input immittance of the. William M. Rabinowitz Research for immittance measurements A closed sound system was calibrated using known acoustic immittances as "loads

  2. Researchers in the faculty of Civil Engineering and

    E-Print Network [OSTI]

    Langendoen, Koen

    . The measurements can be used to predict natural hazards like earthquakes or volcanic eruptions, or to assess, such as oil & gas, transport, infrastructure and construction, rely heavily on geodetic data. Scientifically-called Interferometric Synthetic Aperture Radar systems (InSAR). Pros and cons of InSAR With InSAR it is possible

  3. Very Large Aperture Diffractive Space Telescope

    SciTech Connect (OSTI)

    Hyde, Roderick Allen

    1998-04-20T23:59:59.000Z

    A very large (10's of meters) aperture space telescope including two separate spacecraft--an optical primary functioning as a magnifying glass and an optical secondary functioning as an eyepiece. The spacecraft are spaced up to several kilometers apart with the eyepiece directly behind the magnifying glass ''aiming'' at an intended target with their relative orientation determining the optical axis of the telescope and hence the targets being observed. The magnifying glass includes a very large-aperture, very-thin-membrane, diffractive lens, e.g., a Fresnel lens, which intercepts incoming light over its full aperture and focuses it towards the eyepiece. The eyepiece has a much smaller, meter-scale aperture and is designed to move along the focal surface of the magnifying glass, gathering up the incoming light and converting it to high quality images. The positions of the two space craft are controlled both to maintain a good optical focus and to point at desired targets.

  4. Application of a geocentrifuge and sterolithographically fabricated apertures to multiphase flow in complex fracture apertures.

    SciTech Connect (OSTI)

    Glenn E. McCreery; Robert D. Stedtfeld; Alan T. Stadler; Daphne L. Stoner; Paul Meakin

    2005-09-01T23:59:59.000Z

    A geotechnical centrifuge was used to investigate unsaturated multiphase fluid flow in synthetic fracture apertures under a variety of flow conditions. The geocentrifuge subjected the fluids to centrifugal forces allowing the Bond number to be systematically changed without adjusting the fracture aperture of the fluids. The fracture models were based on the concept that surfaces generated by the fracture of brittle geomaterials have a self-affine fractal geometry. The synthetic fracture surfaces were fabricated from a transparent epoxy photopolymer using sterolithography, and fluid flow through the transparent fracture models was monitored by an optical image acquisition system. Aperture widths were chosen to be representative of the wide range of geological fractures in the vesicular basalt that lies beneath the Idaho Nation Laboratory (INL). Transitions between different flow regimes were observed as the acceleration was changed under constant flow conditions. The experiments showed the transition between straight and meandering rivulets in smooth walled apertures (aperture width = 0.508 mm), the dependence of the rivulet width on acceleration in rough walled fracture apertures (average aperture width = 0.25 mm), unstable meandering flow in rough walled apertures at high acceleration (20g) and the narrowing of the wetted region with increasing acceleration during the penetration of water into an aperture filled with wetted particles (0.875 mm diameter glass spheres).

  5. Monitoring EGS Stimulation and Reservoir Dynamics with InSAR...

    Broader source: Energy.gov (indexed) [DOE]

    Monitoring EGS Stimulation and Reservoir Dynamics with InSAR and MEQ Monitoring EGS Stimulation and Reservoir Dynamics with InSAR and MEQ Monitoring EGS Stimulation and Reservoir...

  6. Processing pharus data with the generic SAR processor

    SciTech Connect (OSTI)

    Otten, M.P.G. [TNO Physics and Electronics Lab., The Hague (Netherlands)

    1996-11-01T23:59:59.000Z

    The Generic SAR Processor (GSP) is a SAR processing environment created to process airborne and spaceborne SAR data with a maximum amount of flexibility, while at the same time providing a user friendly and powerful environment for handling and analyzing SAR, including polarimetric calibration. PHARUS is an airborne polarimetric C-band SAR, utilizing an active (solid state) phased array. The absence of mechanical antenna stabilization, the use of electronic beam steering, in combination with high PRF, polarimetric operation, under motion condition which can be severe, requires a very large flexibility of the SAR processor. The GSP is designed to handle this type of SAR data with a very flexible motion compensation-, azimuth compression-, and radiometric correction approach. First experiences with the processing of PHARUS data show that this is a valid approach to obtain high quality polarimetric imagery with a phased array SAR. 4 refs., 5 figs.

  7. Impulse radar studfinder

    DOE Patents [OSTI]

    McEwan, Thomas E. (Livermore, CA)

    1995-01-01T23:59:59.000Z

    An impulse radar studfinder propagates electromagnetic pulses and detects reflected pulses from a fixed range. Unmodulated pulses, about 200 ps wide, are emitted. A large number of reflected pulses are sampled and averaged. Background reflections are subtracted. Reflections from wall studs or other hidden objects are detected and displayed using light emitting diodes.

  8. Correlations between SAR arc intensity and solar and geomagnetic activity

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ±1960, Rees and Akasofu (1963) and Roach and Roach (1963) found that there are correlations of the SAR arc

  9. Estimating erosional exhumation on Titan from drainage network morphology

    E-Print Network [OSTI]

    Perron, Taylor

    , to estimate cumulative erosion into an initially rough surface. We calibrate this method with a numerical the Cassini spacecraft. While Titan does not host a global surface ocean, Synthetic Aperture Radar (SAR

  10. Depth inversion for nonlinear waves shoaling over a barred-beach 1

    E-Print Network [OSTI]

    Grilli, Stéphan T.

    and calibrated for mild slopes are applied to the barred-beach. Expectedly, errors on depth prediction occur techniques such as Synthetic Aperture Radar (SAR), are still quite problematic under the current state

  11. International Journal of Computer Vision 53(3), 245267, 2003 c 2003 Kluwer Academic Publishers. Manufactured in The Netherlands.

    E-Print Network [OSTI]

    Schechner, Yoav Yosef

    also derive efficient scene sampling conditions as well as ways to self calibrate the vignetting., 1995), remote sensing by synthetic aperture radar (SAR) (Curlander, 1984; Kwok et al., 1990

  12. Noname manuscript No. (will be inserted by the editor)

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    for peacetime and combat Synthetic Aperture Radar (SAR), maritime operations (Naval fire support, over Points (VP) have been established in [7]. Also, VP are widely employed for camera calibrations

  13. Antenna Measurements and Techniques Association (AMTA) Proceedings, Oct. 1996, Seattle WA. A 160 GHZ POLARIMETRIC COMPACT RANGE FOR SCALE MODEL RCS

    E-Print Network [OSTI]

    Massachusetts at Lowell, University of

    calibration. Cross-pol rejection ratios of better than 40 dB are routinely achieved. The compact range) target profiles and synthetic aperture radar (SAR) images. Computer predictions and compact range

  14. Journal of Terrestrial Observation Volume 2, Issue 1 Winter 2010 Article 2

    E-Print Network [OSTI]

    Shan, Jie

    , water depth or inun- dation. Such data are also often used together with the USGS gauge data alongEye, QuickBird, WorldView, SPOT, ALOS PRISM. Also often made available are synthetic aperture radar (SAR

  15. Measuring soil moisture with imaging radars

    SciTech Connect (OSTI)

    Dubois, P.C.; Zyl, J. van [California Inst. of Tech., Pasadena, CA (United States). Jet Propulsion Lab.] [California Inst. of Tech., Pasadena, CA (United States). Jet Propulsion Lab.; Engman, T. [NASA Goddard Space Flight Center, Greenbelt, MD (United States)] [NASA Goddard Space Flight Center, Greenbelt, MD (United States)

    1995-07-01T23:59:59.000Z

    An empirical algorithm for the retrieval of soil moisture content and surface Root Mean Square (RMS) height from remotely sensed radar data was developed using scatterometer data. The algorithm is optimized for bare surfaces and requires two copolarized channels at a frequency between 1.5 and 11 GHz. It gives best results for kh {le} 2.5, {mu}{sub {upsilon}}{le}35%, and {theta}{ge}30{degree}. Omitting the usually weaker hv-polarized returns makes the algorithm less sensitive to system cross-talk and system noise, simplify the calibration process and adds robustness to the algorithm in the presence of vegetation. However, inversion results indicate that significant amounts of vegetation (NDVI>0.4) cause the algorithm to underestimate soil moisture and overestimate RMS height. A simple criteria based on the {sigma}{sub hv}{sup 0}/{sigma}{sub vv}{sup 0} ratio is developed to select the areas where the inversion is not impaired by the vegetation. The inversion accuracy is assessed on the original scatterometer data sets but also on several SAR data sets by comparing the derived soil moisture values with in-situ measurements collected over a variety of scenes between 1991 and 1994. Both spaceborne (SIR-C) and airborne (AIRSAR) data are used in the test. Over this large sample of conditions, the RMS error in the soil moisture estimate is found to be less than 4.2% soil moisture.

  16. Optimal Maneuvers for Distributed Aperture Imaging Systems

    E-Print Network [OSTI]

    Fitch, Danielle

    2012-10-19T23:59:59.000Z

    to the wave vectors (locations in the so-called u-v plane) that are proportional to the relative positions of the apertures. Imaging to specified resolution demands measurement of the Fourier components with adequate signal-to-noise ratio over the interior...

  17. Analysis of transverse apertures in a circular waveguide

    E-Print Network [OSTI]

    Eastham, Gary Bryan

    1989-01-01T23:59:59.000Z

    of a transverse aperture will be extremely useful in the design of coupled cavity resonators and circular cavity backed resonant aperture antennas. B. l. iterature Review Many authors have investigated the effects of apertures in both the transverse... 1989 Major Subject: Electrical Engineering ANALYSIS OF TRANSVERSE APERTURES IN A CIRCULAR WAVEGUIDE A Thesis GARY BRYAN EASTHAM Approved as to style and content by: Kai Chang (Chair of Committee) Brian D. Young (Member) Donal L. Parker...

  18. Radar | Open Energy Information

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-f < RAPID‎ | Roadmap Jump to:b <RGS Development BV JumpRTEV IncRadar

  19. ARM Scanning Radar

    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 Office511041cloth DocumentationProducts (VAP) VAP Update Information on new,Scanning Radar Azores Graciosa

  20. Vacuum aperture isolator for retroreflection from laser-irradiated target

    DOE Patents [OSTI]

    Benjamin, Robert F. (Los Alamos, NM); Mitchell, Kenneth B. (Los Alamos, NM)

    1980-01-01T23:59:59.000Z

    The disclosure is directed to a vacuum aperture isolator for retroreflection of a laser-irradiated target. Within a vacuum chamber are disposed a beam focusing element, a disc having an aperture and a recollimating element. The edge of the focused beam impinges on the edge of the aperture to produce a plasma which refracts any retroreflected light from the laser's target.

  1. Parallel optical nanolithography using nanoscale bowtie aperture array

    E-Print Network [OSTI]

    Xu, Xianfan

    Parallel optical nanolithography using nanoscale bowtie aperture array Sreemanth M.V. Uppuluri of parallel optical nanolithography using nanoscale bowtie aperture array. These nanoscale bowtie aperture1805 photoresist. An interference-based optical alignment system was employed to position the bowtie

  2. Optical nanolithography with k/15 resolution using bowtie aperture array

    E-Print Network [OSTI]

    Xu, Xianfan

    Optical nanolithography with k/15 resolution using bowtie aperture array Xiaolei Wen · Luis M nanolithography using bowtie apertures with the help of the interferometric- spatial-phase-imaging (ISPI) technique. The ISPI system can detect and control the distance between the bowtie aperture, and photoresist

  3. Extraordinary infrared transmission through a periodic bowtie aperture array

    E-Print Network [OSTI]

    Xu, Xianfan

    Extraordinary infrared transmission through a periodic bowtie aperture array Edward C. Kinzel to surface plasmon polariton (SPP) resonances and/or Rayleigh­Wood anomalies (RWA). Bowtie apertures to be strongly resonant. We demonstrate here that the total transmission through a bowtie aperture array can

  4. Complementary bowtie aperture for localizing and enhancing optical magnetic field

    E-Print Network [OSTI]

    Xu, Xianfan

    Complementary bowtie aperture for localizing and enhancing optical magnetic field Nan Zhou, Edward, 2011 Nanoscale bowtie antenna and bowtie aperture antenna have been shown to generate strongly enhanced. In this Letter, we discuss the enhancement of magnetic field intensity of nanoscale complementary bowtie aperture

  5. Dual aperture dipole magnet with second harmonic component

    DOE Patents [OSTI]

    Praeg, W.F.

    1983-08-31T23:59:59.000Z

    An improved dual aperture dipole electromagnet includes a second-harmonic frequency magnetic guide field winding which surrounds first harmonic frequency magnetic guide field windings associated with each aperture. The second harmonic winding and the first harmonic windings cooperate to produce resultant magnetic waveforms in the apertures which have extended acceleration and shortened reset portions of electromagnet operation.

  6. Dual aperture dipole magnet with second harmonic component

    DOE Patents [OSTI]

    Praeg, Walter F. (Palos Park, IL)

    1985-01-01T23:59:59.000Z

    An improved dual aperture dipole electromagnet includes a second-harmonic frequency magnetic guide field winding which surrounds first harmonic frequency magnetic guide field windings associated with each aperture. The second harmonic winding and the first harmonic windings cooperate to produce resultant magnetic waveforms in the apertures which have extended acceleration and shortened reset portions of electromagnet operation.

  7. Forensic Application of FM-CW and Pulse Radar

    SciTech Connect (OSTI)

    S. K. Koppenjan; R. S. Freeland; M. L. Miller; R. E. Yoder

    2003-01-01T23:59:59.000Z

    Ground-penetrating radar (GPR) technology has supplied vital assistance in criminal investigations. However, law enforcement personnel desire further developments such that the technology is rapidly deployable, and that it provides both a simple user interface and sophisticated target identification. To assist in the development of target identification algorithms, our efforts involve gathering background GPR data for the various site conditions and circumstances that often typify clandestine burials. For this study, forensic anthropologists established shallow-grave plots at The University of Tennessee Anthropological Research Facility (ARF) that are specific to GPR research. These plots contain donated human cadavers lying in various configurations and depths, surrounded by assorted construction material and backfill debris. We scanned the plots using two GPR technologies: (1) a multi-frequency synthetic-aperture FM-CW radar (200-700 MHz) (GPR-X) developed by the U.S. Department of Energy's (DOE) Special Technologies Laboratory (STL), Bechtel Nevada (Koppenjan et al., 2000), and (2) a commercial pulse radar (SIR-20) manufactured by Geophysical Survey Systems, Inc. (400 and 900 MHz)(GSSI). The sweep-frequency data show the large biological mass decomposing within the torso as encircled ''hot spots.'' The 400-MHz pulse radar exhibit major horizontal reflectors above the body, with shadow reflectors (horizontal multiples) occurring beneath the body at 60 cm depth. The 400-MHz antenna was able to discern the grave walls and folded tarp covering the lower body. Under these moist, clay-rich conditions, the 900-MHz antenna was able to penetrate slightly beyond 30 cm beneath the concrete layer. However, neither system was able to penetrate beyond a one meter depth in the moist, clay-rich soil (fine, mixed, thermic Typic Paleudalf). Example scans from each system are provided, along with a discussion of the survey protocol and general performance.

  8. Calibration Techniques for Time-Interleaved SAR A/D Converters

    E-Print Network [OSTI]

    Stepanovic, Dusan Vlastimir

    2012-01-01T23:59:59.000Z

    3.4.3 Multi-Channel SAR Calibration . . . . . . . . .3.3.1 Single-Channel Single-Core SAR ADC Calibration . . . .Channel Dual-Core SAR ADC Calibration . . . . 3.3.3 Multi-

  9. Study of spatial scaling in braided river patterns using synthetic aperture radar imagery

    E-Print Network [OSTI]

    Foufoula-Georgiou, Efi

    imagery was used to extract braided river patterns such that their spatial scaling characteristics could to build bridges across sections of braided rivers, to harvest the rich mineral deposits left on their bars, determin- istic approach of water flow over a cohesionless bed. Their model reproduced the main spatial

  10. FOCUS OF ATTENTION FOR MILLIMETER AND ULTRA WIDEBAND SYNTHETIC APERTURE RADAR IMAGERY

    E-Print Network [OSTI]

    Slatton, Clint

    , but is not limited to, Chuan Wang, Doxing Xu and Quin Zhao for useful discussions on signal processing theory

  11. An Approach to Ground Moving Target Indication Using Multiple Resolutions of Multilook Synthetic Aperture Radar Images

    E-Print Network [OSTI]

    Akers, Geoffrey

    2009-12-15T23:59:59.000Z

    D445 u1D461u1D465 (ru1D460,u1D461)u1D445u1D45Fu1D465 (ru1D460,ru1D45F,u1D461) uni222B.alt02 u1D447 u1D452?u1D457u1D7140u1D461?u1D6FF[u1D461?u1D461? ?u1D70F (ru1D460,ru1D45F,u1D461)]u1D460(u1D461?)u1D451u1D461?, (2.8) 17 where T is the transit signal...460)2. Using this approximation and the sifting property of integrating the delta function results in u1D70C(ru1D460,ru1D45F,u1D461) = u1D43A(ru1D460)u1D445(r u1D460) 2u1D452 ?u1D457u1D7140u1D70F(ru1D460,ru1D45F,u1D461)u1D460(u1D461?u1D70F (ru1D460,ru1...

  12. POLAR FORMAT SYNTHETIC APERTURE RADAR IN ENERGY EFFICIENT APPLICATION-SPECIFIC LOGIC-IN-MEMORY

    E-Print Network [OSTI]

    Franchetti, Franz

    perspective transformation, and a local 2D interpolation and supports partial and low to move simple com- putation directly into the memory, and minimize the data movement from memory simple logic instead of actual processing cores right into the memory structures. On an architecture

  13. ARM Climate Research Facility Radar Operations Plan

    SciTech Connect (OSTI)

    Voyles, JW

    2012-05-18T23:59:59.000Z

    Roles, responsibilities, and processes associated with Atmospheric Radiation Measurement (ARM) Radar Operations.

  14. SAR Processing of Radar Echo Sounder Data C. Leuschen , S. Gogineni, D. Tammana

    E-Print Network [OSTI]

    Kansas, University of

    that are mounted under the left and right wings of the aircraft: one for transmission and the other for reception. Each antenna is a four-element dipole array with two-way beamwidths of 18 and 66 degrees in planes

  15. Ground Penetrating Radar, Barrow, Alaska

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

    John Peterson

    This is 500 MHz Ground Penetrating Radar collected along the AB Line in Intensive Site 1 beginning in October 2012 and collected along L2 in Intensive Site 0 beginning in September 2011. Both continue to the present.

  16. SARscape for ENVI A Complete SAR Analysis Solution

    E-Print Network [OSTI]

    SARscape for ENVI A Complete SAR Analysis Solution #12;IDL and ENVI A Foundation for SARscape #12 Support · Certified NITF Read/Write · Calibration Utilities · FLAASH Atmospheric Correction (MODTRAN comprised of 6 modules, 2 base modules and 4 extensions, with more on the way · Very robust variety of SAR

  17. BAYESIAN METHOD FOR SEGMENTATION OF SAR IMAGES IN ROUGH TERRAIN

    E-Print Network [OSTI]

    Oldenburg, Carl von Ossietzky Universität

    BAYESIAN METHOD FOR SEGMENTATION OF SAR IMAGES IN ROUGH TERRAIN Marco Caparrini1 , Klaus Seidel1 are the basis for radiometric correction. Considering SAR images, the huge amount of processing for geographic and geometric calibration and registration that is needed prior to analysis is well established. Nonetheless

  18. Category:SAR | Open Energy Information

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand JumpConceptual Model, click here. Category:ConceptualGeothermal Regulatory Roadmap.sourceSAR page? For

  19. InSAR | Open Energy Information

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation, search OpenEIHesperia,IDGWP WindSatelliteInSAR Jump to: navigation, search

  20. Dual-sided coded-aperture imager

    DOE Patents [OSTI]

    Ziock, Klaus-Peter (Clinton, TN)

    2009-09-22T23:59:59.000Z

    In a vehicle, a single detector plane simultaneously measures radiation coming through two coded-aperture masks, one on either side of the detector. To determine which side of the vehicle a source is, the two shadow masks are inverses of each other, i.e., one is a mask and the other is the anti-mask. All of the data that is collected is processed through two versions of an image reconstruction algorithm. One treats the data as if it were obtained through the mask, the other as though the data is obtained through the anti-mask.

  1. Acoustics of finite-aperture vortex beams

    E-Print Network [OSTI]

    Mitri, F G

    2014-01-01T23:59:59.000Z

    A method based on the Rayleigh-Sommerfeld surface integral is provided, which makes it feasible to rigorously model, evaluate and compute the acoustic scattering and other mechanical effects of finite-aperture vortex beams such as the acoustic radiation force and torque on a viscoelastic sphere in various applications in acoustic tweezers and microfluidics, particle entrapment, manipulation and rotation. Partial-wave series expansions are derived for the incident field of acoustic spiraling (vortex) beams, comprising high-order Bessel and Bessel-Gauss beams.

  2. TWO-DIMENSIONAL POLYNOMIAL PHASE SIGNALS: PARAMETER ESTIMATION AND BOUNDS

    E-Print Network [OSTI]

    Francos, Joseph M.

    , the problem of modeling and analyzing Synthetic Aperture Radar (SAR) data, and in particular Interferometric SAR (INSAR) images, involves the analysis of complex valued 2-D non-homogeneous signals. Perspective such as camera calibration and the computation of shape from texture. Existing solutions to problems where

  3. Space Sci Rev (2010) 150: 285302 DOI 10.1007/s11214-009-9607-5

    E-Print Network [OSTI]

    Spudis, Paul D.

    in spaceborne RF technology and architecture. It combines synthetic aperture radar (SAR) at two wavelengths (S operations will be contemporaneous with India's Chandrayaan-1, which carries the Forerunner Mini-SAR (S calibration, procedures for LRO S. Nozette · P. Spudis Lunar and Planetary Institute, 3600 Bay Area Blvd

  4. 2446 IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 38, NO. 6, NOVEMBER 2000 An Evaluation of the JPL TOPSAR for Extracting

    E-Print Network [OSTI]

    Sarabandi, Kamal

    the interferometric SAR(INSAR) DEM. To accomplish this, differential global po- sitioning system (GPS) measurements. It is accurate to within 1 m or 10% for the red pine test stands used here. Index Terms--Calibration aperture radar (SAR), vegetation. I. INTRODUCTION ONE OF the most critical biophysical parameters

  5. A COMPUTATIONALLY EFFICIENT BLIND ESTIMATOR OF POLYNOMIAL PHASE SIGNALS OBSERVED BY A SENSOR ARRAY

    E-Print Network [OSTI]

    Langendoen, Koen

    Polynomial phase signals (PPSs) are commonly used in synthetic aperture radar (SAR) imaging and radio communications applica- tions (such as the 3GPP standard). For example, in SAR surveillance systems [1 calibrated. In practice, it is difficult to maintain a precisely calibrated array due to pressure, humidity

  6. Great Lakes CoastWatch Research and Product Development Primary Investigator: George Leshkevich -NOAA/GLERL

    E-Print Network [OSTI]

    imagery from new satellite sensors such as synthetic aperture radar (SAR) for ice classification SWA calibration software, the collaboration with researchers at the German Aerospace Center (DLR at the University of Toledo to develop an improved turbidity product and data base: 1. SAR research and field

  7. Open Archive TOULOUSE Archive Ouverte (OATAO) OATAO is an open access repository that collects the work of Toulouse researchers and

    E-Print Network [OSTI]

    Mailhes, Corinne

    of polarization (DoP) is a fundamental quantity characterizing a par- tially polarized electromagnetic field Member, IEEE Abstract--Monitoring and detection of ships and oil spills using synthetic aperture radar coverage and day and night all-weather capabilities of SAR systems. Among different polarimetric SAR modes

  8. Functionalized apertures for the detection of chemical and biological materials

    DOE Patents [OSTI]

    Letant, Sonia E. (Livermore, CA); van Buuren, Anthony W. (Livermore, CA); Terminello, Louis J. (Danville, CA); Thelen, Michael P. (Danville, CA); Hope-Weeks, Louisa J. (Brentwood, CA); Hart, Bradley R. (Brentwood, CA)

    2010-12-14T23:59:59.000Z

    Disclosed are nanometer to micron scale functionalized apertures constructed on a substrate made of glass, carbon, semiconductors or polymeric materials that allow for the real time detection of biological materials or chemical moieties. Many apertures can exist on one substrate allowing for the simultaneous detection of numerous chemical and biological molecules. One embodiment features a macrocyclic ring attached to cross-linkers, wherein the macrocyclic ring has a biological or chemical probe extending through the aperture. Another embodiment achieves functionalization by attaching chemical or biological anchors directly to the walls of the apertures via cross-linkers.

  9. Finding Large Aperture Fractures in Geothermal Resource Areas...

    Broader source: Energy.gov (indexed) [DOE]

    Seismic Survey DOE Geothermal Peer Review 2010 - Presentation. Project summary: Drilling into large aperture open fractures (LAFs) typically yield production wells with...

  10. Finding Large Aperture Fractures in Geothermal Resource Areas...

    Broader source: Energy.gov (indexed) [DOE]

    3-D mapping of Large Aperture Fractures (LAF's) * Budget: 679,000 - Phase 2: Drilling - January-December, 2011. * Task 4: Stepout drilling from existing production wells....

  11. Signal processing for airborne bistatic radar 

    E-Print Network [OSTI]

    Ong, Kian P

    The major problem encountered by an airborne bistatic radar is the suppression of bistatic clutter. Unlike clutter echoes for a sidelooking airborne monostatic radar, bistatic clutter echoes are range dependent. Using ...

  12. Obstacle penetrating dynamic radar imaging system

    DOE Patents [OSTI]

    Romero, Carlos E. (Livermore, CA); Zumstein, James E. (Livermore, CA); Chang, John T. (Danville, CA); Leach, Jr.. Richard R. (Castro Valley, CA)

    2006-12-12T23:59:59.000Z

    An obstacle penetrating dynamic radar imaging system for the detection, tracking, and imaging of an individual, animal, or object comprising a multiplicity of low power ultra wideband radar units that produce a set of return radar signals from the individual, animal, or object, and a processing system for said set of return radar signals for detection, tracking, and imaging of the individual, animal, or object. The system provides a radar video system for detecting and tracking an individual, animal, or object by producing a set of return radar signals from the individual, animal, or object with a multiplicity of low power ultra wideband radar units, and processing said set of return radar signals for detecting and tracking of the individual, animal, or object.

  13. GMTI radar minimum detectable velocity.

    SciTech Connect (OSTI)

    Richards, John Alfred

    2011-04-01T23:59:59.000Z

    Minimum detectable velocity (MDV) is a fundamental consideration for the design, implementation, and exploitation of ground moving-target indication (GMTI) radar imaging modes. All single-phase-center air-to-ground radars are characterized by an MDV, or a minimum radial velocity below which motion of a discrete nonstationary target is indistinguishable from the relative motion between the platform and the ground. Targets with radial velocities less than MDV are typically overwhelmed by endoclutter ground returns, and are thus not generally detectable. Targets with radial velocities greater than MDV typically produce distinct returns falling outside of the endoclutter ground returns, and are thus generally discernible using straightforward detection algorithms. This document provides a straightforward derivation of MDV for an air-to-ground single-phase-center GMTI radar operating in an arbitrary geometry.

  14. 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...

  15. Very high numerical aperture light transmitting device

    DOE Patents [OSTI]

    Allison, Stephen W. (Knoxville, TN); Boatner, Lynn A. (Oak Ridge, TN); Sales, Brian C. (Knoxville, TN)

    1998-01-01T23:59:59.000Z

    A new light-transmitting device using a SCIN glass core and a novel calcium sodium cladding has been developed. The very high index of refraction, radiation hardness, similar solubility for rare earths and similar melt and viscosity characteristics of core and cladding materials makes them attractive for several applications such as high-numerical-aperture optical fibers and specialty lenses. Optical fibers up to 60 m in length have been drawn, and several simple lenses have been designed, ground, and polished. Preliminary results on the ability to directly cast optical components of lead-indium phosphate glass are also discussed as well as the suitability of these glasses as a host medium for rare-earth ion lasers and amplifiers.

  16. Optical aperture synthesis with electronically connected telescopes

    E-Print Network [OSTI]

    Dravins, Dainis; Nuñez, Paul D

    2015-01-01T23:59:59.000Z

    Highest resolution imaging in astronomy is achieved by interferometry, connecting telescopes over increasingly longer distances, and at successively shorter wavelengths. Here, we present the first diffraction-limited images in visual light, produced by an array of independent optical telescopes, connected electronically only, with no optical links between them. With an array of small telescopes, second-order optical coherence of the sources is measured through intensity interferometry over 180 baselines between pairs of telescopes, and two-dimensional images reconstructed. The technique aims at diffraction-limited optical aperture synthesis over kilometre-long baselines to reach resolutions showing details on stellar surfaces and perhaps even the silhouettes of transiting exoplanets. Intensity interferometry circumvents problems of atmospheric turbulence that constrain ordinary interferometry. Since the electronic signal can be copied, many baselines can be built up between dispersed telescopes, and over long...

  17. Coded Aperture Imaging for Fluorescent X-rays-Biomedical Applications

    SciTech Connect (OSTI)

    Haboub, Abdel; MacDowell, Alastair; Marchesini, Stefano; Parkinson, Dilworth

    2013-06-01T23:59:59.000Z

    Employing a coded aperture pattern in front of a charge couple device pixilated detector (CCD) allows for imaging of fluorescent x-rays (6-25KeV) being emitted from samples irradiated with x-rays. Coded apertures encode the angular direction of x-rays and allow for a large Numerical Aperture x- ray imaging system. The algorithm to develop the self-supported coded aperture pattern of the Non Two Holes Touching (NTHT) pattern was developed. The algorithms to reconstruct the x-ray image from the encoded pattern recorded were developed by means of modeling and confirmed by experiments. Samples were irradiated by monochromatic synchrotron x-ray radiation, and fluorescent x-rays from several different test metal samples were imaged through the newly developed coded aperture imaging system. By choice of the exciting energy the different metals were speciated.

  18. Microfabricated high-bandpass foucault aperture for electron microscopy

    DOE Patents [OSTI]

    Glaeser, Robert; Cambie, Rossana; Jin, Jian

    2014-08-26T23:59:59.000Z

    A variant of the Foucault (knife-edge) aperture is disclosed that is designed to provide single-sideband (SSB) contrast at low spatial frequencies but retain conventional double-sideband (DSB) contrast at high spatial frequencies in transmission electron microscopy. The aperture includes a plate with an inner open area, a support extending from the plate at an edge of the open area, a half-circle feature mounted on the support and located at the center of the aperture open area. The radius of the half-circle portion of reciprocal space that is blocked by the aperture can be varied to suit the needs of electron microscopy investigation. The aperture is fabricated from conductive material which is preferably non-oxidizing, such as gold, for example.

  19. Nanoscale ridge aperture as near-field transducer for heat-assisted magnetic recording

    E-Print Network [OSTI]

    Xu, Xianfan

    in a bowtie or half-bowtie shape are capable of generating small optical spots as well as elon- gated optical produced by three types of ridge aperture antennas: the bowtie aperture, half- bowtie aperture, and C

  20. Monitoring EGS Stimulation and Reservoir Dynamics with InSAR...

    Broader source: Energy.gov (indexed) [DOE]

    Monitoring EGS Stimulation and Reservoir Dynamics with InSAR and MEQ, DE-EE0005510 PI: Nicholas C. Davatzes Temple University Topic 4: Observation Tools and Data Collection System...

  1. Fig. 1: 1.25GS/s 8-bit C-2C SAR sub-ADC block diagram Time Interleaved C-2C SAR ADC with Background

    E-Print Network [OSTI]

    Chan Carusone, Tony

    Fig. 1: 1.25GS/s 8-bit C-2C SAR sub-ADC block diagram Time Interleaved C-2C SAR ADC with Background Timing Skew Calibration in 65nm CMOS Luke Wang, Qiwei Wang, and Anthony Chan Carusone Department-bit 40-way time- interleaved SAR ADC fabricated in 65nm CMOS. Two-level hierarchical interleaving

  2. SAR image formation with azimuth interpolation after azimuth transform

    DOE Patents [OSTI]

    Doerry; Armin W. (Albuquerque, NM), Martin; Grant D. (Marlborough, MA), Holzrichter; Michael W. (Albuquerque, NM)

    2008-07-08T23:59:59.000Z

    Two-dimensional SAR data can be processed into a rectangular grid format by subjecting the SAR data to a Fourier transform operation, and thereafter to a corresponding interpolation operation. Because the interpolation operation follows the Fourier transform operation, the interpolation operation can be simplified, and the effect of interpolation errors can be diminished. This provides for the possibility of both reducing the re-grid processing time, and improving the image quality.

  3. Registering coherent change detection products associated with large image sets and long capture intervals

    DOE Patents [OSTI]

    Perkins, David Nikolaus; Gonzales, Antonio I

    2014-04-08T23:59:59.000Z

    A set of co-registered coherent change detection (CCD) products is produced from a set of temporally separated synthetic aperture radar (SAR) images of a target scene. A plurality of transformations are determined, which transformations are respectively for transforming a plurality of the SAR images to a predetermined image coordinate system. The transformations are used to create, from a set of CCD products produced from the set of SAR images, a corresponding set of co-registered CCD products.

  4. Monitoring temperate glaciers by high resolution Pol-InSAR data: First analysis of Argentire E-SAR

    E-Print Network [OSTI]

    Boyer, Edmond

    Monitoring temperate glaciers by high resolution Pol-InSAR data: First analysis of Argentière E to measure temperate glacier velocities and surface characteristics by airborne interferometric Alpine glaciers. Simultaneously to the acquisition of repeat pass interferometric, polarimetric and multi

  5. Two terminal micropower radar sensor

    DOE Patents [OSTI]

    McEwan, Thomas E. (Livermore, CA)

    1995-01-01T23:59:59.000Z

    A simple, low power ultra-wideband radar motion sensor/switch configuration connects a power source and load to ground. The switch is connected to and controlled by the signal output of a radar motion sensor. The power input of the motion sensor is connected to the load through a diode which conducts power to the motion sensor when the switch is open. A storage capacitor or rechargeable battery is connected to the power input of the motion sensor. The storage capacitor or battery is charged when the switch is open and powers the motion sensor when the switch is closed. The motion sensor and switch are connected between the same two terminals between the source/load and ground.

  6. Two terminal micropower radar sensor

    DOE Patents [OSTI]

    McEwan, T.E.

    1995-11-07T23:59:59.000Z

    A simple, low power ultra-wideband radar motion sensor/switch configuration connects a power source and load to ground. The switch is connected to and controlled by the signal output of a radar motion sensor. The power input of the motion sensor is connected to the load through a diode which conducts power to the motion sensor when the switch is open. A storage capacitor or rechargeable battery is connected to the power input of the motion sensor. The storage capacitor or battery is charged when the switch is open and powers the motion sensor when the switch is closed. The motion sensor and switch are connected between the same two terminals between the source/load and ground. 3 figs.

  7. Aperture Arrays for the SKA: Dense or Sparse?

    E-Print Network [OSTI]

    Robert Braun; Wim van Cappellen

    2006-11-06T23:59:59.000Z

    We briefly consider some design aspects of aperture arrays for use in radio astronomy, particularly contrasting the performance of dense and sparse aperture arrays. Recent insights have emerged in the final design phase of LOFAR which suggest that sparse aperture arrays have the best prospects for cost-effective performance at radio frequencies below about 500 MHz; exceeding those of both dense aperture arrays and parabolic reflectors by an order of magnitude. Very attractive performance, of 10,000 - 20,000 m2/K, can be achieved with a sparse design that covers the 70 - 700 MHz range with two antenna systems that share receiver resources. Cost-effective systems of this type represent only a modest increment in system complexity over that being deployed in LOFAR and are achievable with today's technology.

  8. aperture optical system: Topics by E-print Network

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

    20 21 22 23 24 25 Next Page Last Page Topic Index 1 May 15, 2003 Vol. 28, No. 10 OPTICS LETTERS 801 Phase retrieval for high-numerical-aperture optical systems Biotechnology...

  9. 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...

  10. aperture single photon: Topics by E-print Network

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

    emitting diode where current may be injected into a single dot. D. J. P. Ellis; A. J. Bennett; A. J. Shields; P. Atkinson; D. A. Ritchie 2007-09-13 4 Oxide-apertured microcavity...

  11. Receiver for solar energy collector having improved aperture aspect

    DOE Patents [OSTI]

    McIntire, William R. (Downers Grove, IL)

    1984-01-01T23:59:59.000Z

    A secondary concentrator for use in receiver systems for linear focusing primary concentrators is provided with reflector wings at each end. The wings increase the capture of light rays reflected from areas adjacent the rim of a primary concentrator, increasing the apparent aperture size of the absorber as viewed from the rim of the primary concentrator. The length, tilt, and curvature of the wing reflectors can be adjusted to provide an absorber having a desired aperture aspect.

  12. Transmission of High-Power Electron Beams Through Small Apertures

    SciTech Connect (OSTI)

    Tschalaer, Christoph [MIT Bates Linear Accelerator; Alarcon, Ricardo O.; Balascuta, S.; Benson, Stephen V. [JLAB; Bertozzi, William; Boyce, James R. [College of William and Mary; Cowan, Ray Franklin [MIT; Douglas, David R. [JLAB; Evtushenko, Pavel [JLAB; Fisher, Peter H.; Ihloff, Ernest E. [MIT Bates Linear Accelerator; Kalantarians, Narbe [Unversity of Texas; Kelleher, Aidan Michael [MIT Bates Linear Accelerator; Legg, Robert A. [JLAB; Milner, Richard; Neil, George R. [JLAB; Ou, Longwu [MIT; Schmookler, Barak Abraham [MIT; Tennant, Christopher D. [JLAB; Williams, Gwyn P. [JLAB; Zhang, Shukui [JLAB

    2013-11-01T23:59:59.000Z

    Tests were performed to pass a 100 MeV, 430 kWatt c.w. electron beam from the energy-recovery linac at the Jefferson Laboratory's FEL facility through a set of small apertures in a 127 mm long aluminum block. Beam transmission losses of 3 p.p.m. through a 2 mm diameter aperture were maintained during a 7 hour continuous run.

  13. Minimizing Biases in Radar Precipitation Estimates

    E-Print Network [OSTI]

    McRoberts, Douglas B

    2014-12-08T23:59:59.000Z

    ................................................................................................. 57 3.4 The same as Fig. 3.3b, but with HRAP grid cells detected by the flagging algorithm (gray diamonds) in the 90 km – 100 km annulus in the KABR radar domain .......................................................................... 62 3.5... ...................... 163 xiii FIGURE Page 5.1 Same as Fig. 3.1, but without radar locations or boundaries for radar domains ................................................................................................... 169 5.2 (a) Stage IV 1-month Po...

  14. A land based radar polarimeter processing system

    E-Print Network [OSTI]

    Kronke, Chester William

    1984-01-01T23:59:59.000Z

    Assignments 4 Indicator Circuit Read Port Assignments. 5 Interpretation of Indicator Circuit Data . 6 RF Head Common Control Port Signal Assignments . 7 iSBC-80/24 Parallel I/O Summary. 8 iSBX-311 Analog Input Signal Assignments 9 Memory Map... Polarimeter Antennas 2 Azimuthal Angle of Radar Polarimeter Boom. 3 Block Diagram of the Radar Polarimeter System. 4 Block Diagram of Radar Hardware. 10 5 Microwave Transceiver Circuit Transfer Switches Controlled by RDADS. 12 6 Block Diagram...

  15. Radar range measurements in the atmosphere.

    SciTech Connect (OSTI)

    Doerry, Armin Walter

    2013-02-01T23:59:59.000Z

    The earth's atmosphere affects the velocity of propagation of microwave signals. This imparts a range error to radar range measurements that assume the typical simplistic model for propagation velocity. This range error is a function of atmospheric constituents, such as water vapor, as well as the geometry of the radar data collection, notably altitude and range. Models are presented for calculating atmospheric effects on radar range measurements, and compared against more elaborate atmospheric models.

  16. Radar network communication through sensing of frequency hopping

    DOE Patents [OSTI]

    Dowla, Farid; Nekoogar, Faranak

    2013-05-28T23:59:59.000Z

    In one embodiment, a radar communication system includes a plurality of radars having a communication range and being capable of operating at a sensing frequency and a reporting frequency, wherein the reporting frequency is different than the sensing frequency, each radar is adapted for operating at the sensing frequency until an event is detected, each radar in the plurality of radars has an identification/location frequency for reporting information different from the sensing frequency, a first radar of the radars which senses the event sends a reporting frequency corresponding to its identification/location frequency when the event is detected, and all other radars in the plurality of radars switch their reporting frequencies to match the reporting frequency of the first radar upon detecting the reporting frequency switch of a radar within the communication range. In another embodiment, a method is presented for communicating information in a radar system.

  17. Proceedings OceanSAR 2006 Third Workshop on Coastal and Marine Applications of SAR, St. John's, NL, Canada, October 2006 Algorithm development for operational satellite SAR

    E-Print Network [OSTI]

    -section to establish a library of signatures (look-up table) for different ice types. Using this library of signatures, a library of backscatter signatures for different ice types is needed for use with calibrated SAR imagery. 2 types using the Jet Propulsion Laboratory (JPL) C-band scatterometer, together with surface-based ice

  18. Sandia Energy - TTU Advanced Doppler Radar

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

    radar technologies and techniques developed at TTU have the potential to revolutionize wind energy generation by providing comprehensive information about the modulated flows...

  19. Radar investigation of the Hockley salt dome

    E-Print Network [OSTI]

    Hluchanek, James Andrew

    1973-01-01T23:59:59.000Z

    : Geophysics RADAR INVESTIGATION OF THE HOCKLEY SALT DOME A Thesis by UAMES ANDREW HLUCHANEK A'pproved as to style and content by: (Head of Departme t ? Member) May 1. 973 ABSTRACT Radar investigation of the Hockley Salt Dome. . (Nay, 1973) James... Andrew Hluchanek, B. S. , Texas A&M University Directed by: Dr. Robert R. Unterberger Radar probing through salt was accomplished at 17 radar stations established in the United Salt Company mine at Hockley, Texas. The top of the salt dom is mapped...

  20. Sandia National Laboratories: TTU Advanced Doppler Radar

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

    rotor sweep. Doppler radar technologies and techniques developed at TTU have the potential to revolutionize wind energy generation by providing comprehensive information...

  1. Influence of phase fluctuations in the troposphere on SAR calibration accuracy

    SciTech Connect (OSTI)

    Velichko, S.A.; Kuleminn, G.P.; Lukin, V.V. [and others

    1996-11-01T23:59:59.000Z

    The conditions of SAR signal propagation through a turbulent troposphere and precipitations are discussed. The statistical and spectral-correlation characteristics of received signal amplitude and phase fluctuations caused by these factors are evaluated for spaceborne and airborne SARs. The numerical simulation results dealing with SAR response parameter statistical analysis are presented. They demonstrate the possible strong degradation of the response resulting in low accuracy of SAR calibration for high frequencies and great angles of Earth surface vision. 15 refs., 2 tabs.

  2. Sandia National Laboratories: National Air Space radar system

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

    Air Space radar system Sandia Develops Tool to Evaluate Wind-TurbineRadar Impacts On December 3, 2014, in Computational Modeling & Simulation, Energy, News, News & Events,...

  3. Surface deformation analysis over a hydrocarbon reservoir using InSAR with ALOS-PALSAR data

    E-Print Network [OSTI]

    ?ahin, Sedar Cihan

    2013-01-01T23:59:59.000Z

    InSAR has been developed to estimate the temporal change on the surface of Earth by combining multiple SAR images acquired over the same area at different times. In the last two decades, in addition to conventional InSAR, ...

  4. ATTEMPT OF ALPINE GLACIER FLOW MODELING BASED ON CORRELATION MEASUREMENTS OF HIGH RESOLUTION SAR IMAGES

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ATTEMPT OF ALPINE GLACIER FLOW MODELING BASED ON CORRELATION MEASUREMENTS OF HIGH RESOLUTION SAR In this paper, an attempt of Alpine glacier flow modeling is performed based on a series of high resolution TerraSAR-X SAR images and a Digital Elevation Model. First, a glacier flow model is established

  5. 4B.3 The Sounding Analog Retrieval System (SARS) Ryan Jewell1

    E-Print Network [OSTI]

    that are determined from a calibration process. For severe hail, SARS has been designed to forecast the probability4B.3 The Sounding Analog Retrieval System (SARS) Ryan Jewell1 Storm Prediction Center, Norman, OK 1 System (SARS) is a forecasting algorithm that uses sounding derived parameters to find historical severe

  6. IMPROVED PROCESSING OF THE CASIE SAR DATA Craig Stringham and David G. Long

    E-Print Network [OSTI]

    Long, David G.

    collected for other CASIE sensors can be employed to improve the SAR image focus and calibration. The 160-aligned motion data enables better SAR image focusing and calibration. This paper summarizes how these estimatesIMPROVED PROCESSING OF THE CASIE SAR DATA Craig Stringham and David G. Long Microwave Earth Remote

  7. CORRELATION BETWEEN ANTARCTIC DRY SNOW PROPERTIES AND BACKSCATTERING CHARACTERISTICS IN RADARSAT SAR IMAGERY

    E-Print Network [OSTI]

    Oldenburg, Carl von Ossietzky Universität

    SAR IMAGERY N. Zahnen1 , F. Jung-Rothenhäusler2,3 , H. Oerter2 , F. Wilhelms2 and H. Miller2 1 in RADARSAT SAR imagery. Twenty-six RADARSAT SAR standard beam images acquired in May 1997 are analysed. Process- ing steps include radiometric calibration, geometric correction and the generation of a mosaic

  8. Radar MeteorologyRadar Meteorology Feb 20, 1941 10 cm (S-band) radar used to track rain showers (Ligda)

    E-Print Network [OSTI]

    Rutledge, Steven

    (Ligda) Possibility of such observations was predicted by Ryde (1941) MIT Radiation Laboratory made in 1943 First operational weather radar, Panama, 1943 Science of radar meteorology born from WWII research fluctuations at 1/2 the wavelength of the incident radiation (a few meters in this case). Power returned from

  9. Hydraulic transmissivity and heat exchanges: aperture lowpass filtering model 1 Natural open joints in rocks commonly present multi-scale self-affine apertures. This

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Hydraulic transmissivity and heat exchanges: aperture lowpass filtering model 1 SUMMARY Natural aperture that describes at best the macroscopic properties (hydraulic conductivity, heat exchange of the effective hydraulic and thermal properties (apertures). A detailed study of the influence of the bandwidth

  10. Ultra-wideband radar sensors and networks

    DOE Patents [OSTI]

    Leach, Jr., Richard R; Nekoogar, Faranak; Haugen, Peter C

    2013-08-06T23:59:59.000Z

    Ultra wideband radar motion sensors strategically placed in an area of interest communicate with a wireless ad hoc network to provide remote area surveillance. Swept range impulse radar and a heart and respiration monitor combined with the motion sensor further improves discrimination.

  11. Sandia Energy - Radar Friendly Blades

    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 Sol Home Distribution Grid IntegrationOffshoreLiveSustainablePriceRadar

  12. Computing the apparent centroid of radar targets

    SciTech Connect (OSTI)

    Lee, C.E.

    1996-12-31T23:59:59.000Z

    A high-frequency multibounce radar scattering code was used as a simulation platform for demonstrating an algorithm to compute the ARC of specific radar targets. To illustrate this simulation process, several targets models were used. Simulation results for a sphere model were used to determine the errors of approximation associated with the simulation; verifying the process. The severity of glint induced tracking errors was also illustrated using a model of an F-15 aircraft. It was shown, in a deterministic manner, that the ARC of a target can fall well outside its physical extent. Finally, the apparent radar centroid simulation based on a ray casting procedure is well suited for use on most massively parallel computing platforms and could lead to the development of a near real-time radar tracking simulation for applications such as endgame fuzing, survivability, and vulnerability analyses using specific radar targets and fuze algorithms.

  13. Tangential velocity measurement using interferometric MTI radar

    DOE Patents [OSTI]

    Doerry, Armin W.; Mileshosky, Brian P.; Bickel, Douglas L.

    2006-01-03T23:59:59.000Z

    Radar systems use time delay measurements between a transmitted signal and its echo to calculate range to a target. Ranges that change with time cause a Doppler offset in phase and frequency of the echo. Consequently, the closing velocity between target and radar can be measured by measuring the Doppler offset of the echo. The closing velocity is also known as radial velocity, or line-of-sight velocity. Doppler frequency is measured in a pulse-Doppler radar as a linear phase shift over a set of radar pulses during some Coherent Processing Interval (CPI). An Interferometric Moving Target Indicator (MTI) radar can be used to measure the tangential velocity component of a moving target. Multiple baselines, along with the conventional radial velocity measurement, allow estimating the true 3-D velocity of a target.

  14. Magneto-Radar Hidden Metal Detector

    DOE Patents [OSTI]

    McEwan, Thomas E. (Las Vegas, NV)

    2005-07-05T23:59:59.000Z

    A varying magnetic field excites slight vibrations in an object and a radar sensor detects the vibrations at a harmonic of the excitation frequency. The synergy of the magnetic excitation and radar detection provides increased detection range compared to conventional magnetic metal detectors. The radar rejects background clutter by responding only to reflecting objects that are vibrating at a harmonic excitation field, thereby significantly improving detection reliability. As an exemplary arrangement, an ultra-wideband micropower impulse radar (MIR) is capable of being employed to provide superior materials penetration while providing range information. The magneto-radar may be applied to pre-screening magnetic resonance imaging (MRI) patients, landmine detection and finding hidden treasures.

  15. Wind energy calculated from SAR and scatterometer satellite data

    E-Print Network [OSTI]

    Slide no. The WAsP icon #12;1 8 Slide no. Wind observations #12;1 9 Slide no. European Wind Atlas #121 Slide no. 4 Wind energy calculated from SAR and scatterometer satellite data Charlotte Bay, Italy, 23-24 June 2003 #12;2 Slide no. 4 Presentation · Risø National Laboratory/ Wind Energy Dept

  16. Automatic Extraction of Cartographic Information from Airborne Interferometric SAR Data

    E-Print Network [OSTI]

    Mayer, Helmut A.

    Automatic Extraction of Cartographic Information from Airborne Interferometric SAR Data Reinhold cartographic feature extraction by the airborne AeS--1 instrument is presented. We extract regions corresponding to cartographic features for the classes built--up area, forest, water and open area. Water

  17. Ris-R-1298(EN) Validation of Satellite SAR Offshore

    E-Print Network [OSTI]

    resources, e.g. in future planning of offshore wind farms. The report describes the validation analysisRisø-R-1298(EN) Validation of Satellite SAR Offshore Wind Speed Maps to In-Situ Data, Microscale project goal is to develop a method for utilizing the satellite wind speed maps for offshore wind

  18. absorption rate sar: Topics by E-print Network

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

    absorption rate sar First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Original Research Specific...

  19. Observations of colocated optical and radar aurora H. Bahcivan,1

    E-Print Network [OSTI]

    Lummerzheim, Dirk

    Observations of colocated optical and radar aurora H. Bahcivan,1 D. L. Hysell,2 D. Lummerzheim,3 M of the E region radar aurora obtained with a 30 MHz imaging radar and the optical aurora (green line, the radar aurora in the vicinity of a stable evening auroral arc arises because of the arc's polarization

  20. Development of the Solid State X-band Radar and the Phased Array Radar System in Japan

    E-Print Network [OSTI]

    Droegemeier, Kelvin K.

    Development of the Solid State X-band Radar and the Phased Array Radar System in Japan By DR. TOMOO array radar system have been developed. Toshiba has developed the latest model of weather radar of precipitation and to achieve drastic reduction of its size and life cycle cost. It is now well known

  1. Using doppler radar images to estimate aircraft navigational heading error

    DOE Patents [OSTI]

    Doerry, Armin W. (Albuquerque, NM); Jordan, Jay D. (Albuquerque, NM); Kim, Theodore J. (Albuquerque, NM)

    2012-07-03T23:59:59.000Z

    A yaw angle error of a motion measurement system carried on an aircraft for navigation is estimated from Doppler radar images captured using the aircraft. At least two radar pulses aimed at respectively different physical locations in a targeted area are transmitted from a radar antenna carried on the aircraft. At least two Doppler radar images that respectively correspond to the at least two transmitted radar pulses are produced. These images are used to produce an estimate of the yaw angle error.

  2. aperture optics system: Topics by E-print Network

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

    aperture optics system First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 May 15, 2003 Vol. 28, No. 10 ...

  3. aperture icf optics: Topics by E-print Network

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

    aperture icf optics First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Advanced Optics Experiments Using...

  4. aperture shield materials: Topics by E-print Network

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

    aperture shield materials First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Light-weight Flexible...

  5. Microwave-induced thermoacoustic tomography: Reconstruction by synthetic aperture

    E-Print Network [OSTI]

    Wang, Lihong

    Microwave-induced thermoacoustic tomography: Reconstruction by synthetic aperture Dazi Feng, Yuan thermoacoustic signals, to which the delay-and-sum algorithm was applied for image reconstruc- tion. We greatly-induced thermoacoustic tomography based on focused transducers. Two mi- crowave sources, which had frequencies of 9 and 3

  6. Imaging Fourier transform spectroscopy with multi-aperture telescopes

    E-Print Network [OSTI]

    Fienup, James R.

    Imaging Fourier transform spectroscopy with multi-aperture telescopes Samuel T. Thurman and James R Hanover St., Palo Alto, CA 94304 Abstract: Fourier spectroscopy can be performed with multi Society of America OCIS codes: (300.6300) Spectroscopy, Fourier transforms; (110.6770) Telescopes; (120

  7. Comparing synthetic aperture radar and LiDAR for above-ground biomass estimation in Glen Affric, Scotland 

    E-Print Network [OSTI]

    Tan, Chue Poh

    2012-06-25T23:59:59.000Z

    Quantifying above-ground biomass (AGB) and carbon sequestration has been a significant focus of attention within the UNFCCC and Kyoto Protocol for improvement of national carbon accounting systems (IPCC, 2007; UNFCCC, ...

  8. Reservoir monitoring and characterization using satellite geodetic data: Interferometric Synthetic Aperture Radar observations from the Krechba field, Algeria

    E-Print Network [OSTI]

    Vasco, D.W.

    2008-01-01T23:59:59.000Z

    activity at the Cold Lake heavy oil ?eld, Alberta, Canada:Thermal Op- erations and Heavy Oil Symposium, CHOA 97848,

  9. Inversion of synthetic aperture radar interferograms for sources of production-related subsidence at the Dixie Valley geothermal field

    E-Print Network [OSTI]

    Foxall, B.; Vasco, D.W.

    2008-01-01T23:59:59.000Z

    site and the Okuaizu geothermal field, Japan", Geothermics,at the Cerro Prieto geothermal field, Baja California,and seismicity in the Coso geothermal area, Inyo County,

  10. Use of synthetic aperture radar for offshore wind resource assessment and wind farm development in the UK 

    E-Print Network [OSTI]

    Cameron, Iain Dickson

    2008-01-01T23:59:59.000Z

    The UK has an abundant offshore wind resource with offshore wind farming set to grow rapidly over the coming years. Optimisation of energy production is of the utmost importance and accurate estimates of wind speed distributions are critical...

  11. Abstract--Synthetic aperture radar has become an important technique for generating high-resolution images of the ground,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    velocity vector, because of the Doppler shift dependency on azimuthal position and radial velocity of the Doppler shift dependence on both azimuthal position and radial velocity of the moving target [15]. 2 is nowadays well mastered. If targets are moving, it induces a delocalization and a defocusing effect

  12. Reservoir monitoring and characterization using satellite geodetic data: Interferometric Synthetic Aperture Radar observations from the Krechba field, Algeria

    E-Print Network [OSTI]

    Vasco, D.W.

    2008-01-01T23:59:59.000Z

    because we have no reservoir pressure data u(t) = ?v f (t).of reservoir properties using transient pressure data: AnReservoir monitoring and characterization using geodetic data

  13. An RF dosimeter for independent SAR measurement in MRI scanners

    SciTech Connect (OSTI)

    Qian, Di; Bottomley, Paul A. [Division of MR Research, Department of Radiology, Johns Hopkins School of Medicine, Baltimore, Maryland 21287 and Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, Maryland 21218 (United States)] [Division of MR Research, Department of Radiology, Johns Hopkins School of Medicine, Baltimore, Maryland 21287 and Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, Maryland 21218 (United States); El-Sharkawy, AbdEl-Monem M.; Edelstein, William A., E-mail: w.edelstein@gmail.com [Division of MR Research, Department of Radiology, Johns Hopkins School of Medicine, Baltimore, Maryland 21287 (United States)

    2013-12-15T23:59:59.000Z

    Purpose: The monitoring and management of radio frequency (RF) exposure is critical for ensuring magnetic resonance imaging (MRI) safety. Commercial MRI scanners can overestimate specific absorption rates (SAR) and improperly restrict clinical MRI scans or the application of new MRI sequences, while underestimation of SAR can lead to tissue heating and thermal injury. Accurate scanner-independent RF dosimetry is essential for measuring actual exposure when SAR is critical for ensuring regulatory compliance and MRI safety, for establishing RF exposure while evaluating interventional leads and devices, and for routine MRI quality assessment by medical physicists. However, at present there are no scanner-independent SAR dosimeters. Methods: An SAR dosimeter with an RF transducer comprises two orthogonal, rectangular copper loops and a spherical MRI phantom. The transducer is placed in the magnet bore and calibrated to approximate the resistive loading of the scanner's whole-body birdcage RF coil for human subjects in Philips, GE and Siemens 3 tesla (3T) MRI scanners. The transducer loop reactances are adjusted to minimize interference with the transmit RF field (B{sub 1}) at the MRI frequency. Power from the RF transducer is sampled with a high dynamic range power monitor and recorded on a computer. The deposited power is calibrated and tested on eight different MRI scanners. Whole-body absorbed power vs weight and body mass index (BMI) is measured directly on 26 subjects. Results: A single linear calibration curve sufficed for RF dosimetry at 127.8 MHz on three different Philips and three GE 3T MRI scanners. An RF dosimeter operating at 123.2 MHz on two Siemens 3T scanners required a separate transducer and a slightly different calibration curve. Measurement accuracy was ?3%. With the torso landmarked at the xiphoid, human adult whole?body absorbed power varied approximately linearly with patient weight and BMI. This indicates that whole-body torso SAR is on average independent of the imaging subject, albeit with fluctuations. Conclusions: Our 3T RF dosimeter and transducers accurately measure RF exposure in body-equivalent loads and provide scanner-independent assessments of whole-body RF power deposition for establishing safety compliance useful for MRI sequence and device testing.

  14. Radar echo signatures versus relative precipitation

    E-Print Network [OSTI]

    Huber, Terry Alvin

    1987-01-01T23:59:59.000Z

    the relationship between cell-echo signatures and precipitation characteristics, and to support the hypothesis that, during the lifespan of any particular isolated convective cell, the relative rainfall rate, as determined by radar for a given volume scan... Cooperative Program) field experiment of 1979. Four isolated cases, two rainshowers and two thundershowers, were selected for study. Profiles from volume scans taken 10 minutes before, during, and 10 minutes after the maximum radar-determined rainfall rate...

  15. High transmission nanoscale bowtie-shaped aperture probe for near-field optical imaging

    E-Print Network [OSTI]

    Xu, Xianfan

    High transmission nanoscale bowtie-shaped aperture probe for near-field optical imaging Liang Wang probe integrated with nanoscale bowtie aperture for enhanced optical transmission is demonstrated. The bowtie-shape aperture allows a propagating mode in the bowtie gap region, which enables simultaneous

  16. Improving near-field confinement of a bowtie aperture using surface plasmon polaritons

    E-Print Network [OSTI]

    Xu, Xianfan

    Improving near-field confinement of a bowtie aperture using surface plasmon polaritons Pornsak; published online 1 June 2011 Bowtie aperture is known to produce subdiffraction-limited optical spot with high intensity. In this work, we investigate integrating a bowtie aperture with circular grooves

  17. Enhanced optical near field from a bowtie aperture Eric X. Jin and Xianfan Xua

    E-Print Network [OSTI]

    Xu, Xianfan

    Enhanced optical near field from a bowtie aperture Eric X. Jin and Xianfan Xua School of Mechanical 2006; published online 11 April 2006 The enhanced optical near field from a bowtie aperture of the same opening area. Light concentration and transmission enhancement of bowtie apertures promise

  18. Ground Penetrating Radar in Hydrogeophysics

    SciTech Connect (OSTI)

    Hubbard, Susan; Lambot, S.; Binley, A.; Slob, E.; Hubbard, S.

    2008-01-15T23:59:59.000Z

    To meet the needs of a growing population and to provide us with a higher quality of life, increasing pressures are being placed on our environment through the development of agriculture, industry, and infrastructures. Soil erosion, groundwater depletion, salinization, and pollution have been recognized for decades as major threats to ecosystems and human health. More recently, the progressive substitution of fossil fuels by biofuels for energy production and climate change have been recognized as potential threats to our water resources and sustained agricultural productivity. The vadose zone mediates many of the processes that govern water resources and quality, such as the partition of precipitation into infiltration and runoff , groundwater recharge, contaminant transport, plant growth, evaporation, and energy exchanges between the Earth's surface and its atmosphere. It also determines soil organic carbon sequestration and carbon-cycle feedbacks, which could substantially impact climate change. The vadose zone's inherent spatial variability and inaccessibility precludes direct observation of the important subsurface processes. In a societal context where the development of sustainable and optimal environmental management strategies has become a priority, there is a strong prerequisite for the development of noninvasive characterization and monitoring techniques of the vadose zone. In particular, hydrogeophysical approaches applied at relevant scales are required to appraise dynamic subsurface phenomena and to develop optimal sustainability, exploitation, and remediation strategies. Among existing geophysical techniques, ground penetrating radar (GPR) technology is of particular interest for providing high-resolution subsurface images and specifically addressing water-related questions. Ground penetrating radar is based on the transmission and reception of VHF-UHF (30-3000 MHz) electromagnetic waves into the ground, whose propagation is determined by the soil electromagnetic properties and their spatial distribution. As the dielectric permittivity of water overwhelms the permittivity of other soil components, the presence of water in the soil principally governs GPR wave propagation. Therefore, GPR-derived dielectric permittivity is usually used as surrogate measure for soil water content. In the areas of unsaturated zone hydrology and water resources, GPR has been used to identify soil stratigraphy, to locate water tables, to follow wetting front movement, to estimate soil water content, to assist in subsurface hydraulic parameter identification, to assess soil salinity, and to support the monitoring of contaminants. The purpose of this special section of the Vadose Zone Journal is to present recent research advances and applications of GPR in hydrogeophysics, with a particular emphasis on vadose zone investigations. This special section includes contributions presented at the European Geosciences Union General Assembly 2006 (EGU 2006, Vienna, Austria) and the 11th International Conference on Ground Penetrating Radar (GPR 2006, Columbus, OH). The studies presented here deal with a wide range of surface and borehole GPR applications, including GPR sensitivity to contaminant plumes, new methods for soil water content determination, three-dimensional imaging of the subsurface, time-lapse monitoring of hydrodynamic events and inversion techniques for soil hydraulic properties estimation, and joint interpretation of GPR and electric resistivity tomography (ERT) data.

  19. A high-resolution, four-band SAR testbed with real-time image formation

    SciTech Connect (OSTI)

    Walker, B.; Sander, G.; Thompson, M.; Burns, B.; Fellerhoff, R.; Dubbert, D.

    1996-03-01T23:59:59.000Z

    This paper describes the Twin-Otter SAR Testbed developed at Sandia National Laboratories. This SAR is a flexible, adaptable testbed capable of operation on four frequency bands: Ka, Ku, X, and VHF/UHF bands. The SAR features real-time image formation at fine resolution in spotlight and stripmap modes. High-quality images are formed in real time using the overlapped subaperture (OSA) image-formation and phase gradient autofocus (PGA) algorithms.

  20. The Accuracy of Radar Estimates of Ice Terminal Fall Speed from Vertically Pointing Doppler Radar Measurements

    E-Print Network [OSTI]

    Protat, Alain

    The Accuracy of Radar Estimates of Ice Terminal Fall Speed from Vertically Pointing Doppler Radar and 2835 MHz) are used to characterize the terminal fall speed of hydrometeors and the vertical air motion air velocity in ice clouds is small on average, as is assumed in terminal fall speed retrieval methods

  1. Stepped frequency ground penetrating radar

    DOE Patents [OSTI]

    Vadnais, Kenneth G. (Ojai, CA); Bashforth, Michael B. (Buellton, CA); Lewallen, Tricia S. (Ventura, CA); Nammath, Sharyn R. (Santa Barbara, CA)

    1994-01-01T23:59:59.000Z

    A stepped frequency ground penetrating radar system is described comprising an RF signal generating section capable of producing stepped frequency signals in spaced and equal increments of time and frequency over a preselected bandwidth which serves as a common RF signal source for both a transmit portion and a receive portion of the system. In the transmit portion of the system the signal is processed into in-phase and quadrature signals which are then amplified and then transmitted toward a target. The reflected signals from the target are then received by a receive antenna and mixed with a reference signal from the common RF signal source in a mixer whose output is then fed through a low pass filter. The DC output, after amplification and demodulation, is digitized and converted into a frequency domain signal by a Fast Fourier Transform. A plot of the frequency domain signals from all of the stepped frequencies broadcast toward and received from the target yields information concerning the range (distance) and cross section (size) of the target.

  2. Transmission of Megawatt Relativistic Electron Beams Through Millimeter Apertures

    SciTech Connect (OSTI)

    Arizona State University; Arizona State University; JLAB; MIT; College of William and Mary, JLAB; MIT; JLAB; JLAB; MIT; MIT; Hampton University; MIT; JLAB; MIT; JLAB; MIT; MIT; JLAB; MIT; JLAB; JLAB

    2013-10-01T23:59:59.000Z

    High power, relativistic electron beams from energy recovery linacs have great potential to realize new experimental paradigms for pioneering research in fundamental and applied research. A major design consideration for these new generation of experimental capabilities is the understanding of the halo associated with these bright, intense beams. In this Letter, we report on measurements performed using the 100 MeV, 430 kWatt CW electron beam from the energy recovery linac at the Jeff#11;erson Laboratory's Free Electron Laser facility as it traversed a set of small apertures in a 127 mm long aluminum block. Thermal measurements of the block together with neutron measurements near the beam-target interaction point yielded a consistent understanding of the beam losses. These were determined to be 3 ppm through a 2 mm diameter aperture and were maintained during a 7 hour continuous run.

  3. The integration of Human Factors (HF) in the SAR process training course text

    SciTech Connect (OSTI)

    Ryan, T.G.

    1995-03-01T23:59:59.000Z

    This text provides the technical basis for a two-day course on human factors (HF), as applied to the Safety Analysis Report (SAR) process. The overall objective of this text and course is to: provide the participant with a working knowledge of human factors-related requirements, suggestions for doing a human safety analysis applying a graded approach, and an ability to demonstrate using the results of the human safety analysis, that human factors elements as defined by DOE (human factors engineering, procedures, training, oversight, staffing, qualifications), can support wherever necessary, nuclear safety commitments in the SAR. More specifically, the objectives of the text and course are: (1) To provide the SAR preparer with general guidelines for doing HE within the context of a graded approach for the SAR; (2) To sensitize DOE facility managers and staff, safety analysts and SAR preparers, independent reviewers, and DOE reviewers and regulators, to DOE Order 5480.23 requirements for HE in the SAR; (3) To provide managers, analysts, reviewers and regulators with a working knowledge of HE concepts and techniques within the context of a graded approach for the SAR, and (4) To provide SAR managers and DOE reviewers and regulators with general guidelines for monitoring and coordinating the work of preparers of HE inputs throughout the SAR process, and for making decisions regarding the safety relevance of HE inputs to the SAR. As a ready reference for implementing the human factors requirements of DOE Order 5480.22 and DOE Standard 3009-94, this course text and accompanying two-day course are intended for all persons who are involved in the SAR.

  4. Influence of radar frequency on the relationship between bare surface soil moisture vertical profile and radar backscatter

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    produced from Envisat ASAR and TerraSAR-X data, acquired over bare soils with in situ measurements heterogeneity into account in the backscatter model. Key words: SAR, AIEM, soil moisture profile, bare soil hal in the L, C, and X frequency bands, empirical and semi-empirical models are often calibrated using soil

  5. Tracking butterfly flight paths across the landscape with harmonic radar

    E-Print Network [OSTI]

    Northampton, University of

    Tracking butterfly flight paths across the landscape with harmonic radar E. T. Cant1,*, A. D. Smith of five butterfly species were successfully tracked using harmonic radar within an agricultural landscape. Keywords: butterfly flight; harmonic radar; linear landscape features; Aglais urticae; Inachis io 1

  6. Bias adjustment of radar-based 3-hour precipitation accumulations

    E-Print Network [OSTI]

    Stoffelen, Ad

    projection of KNMI radar images 55 4 #12;Chapter 1 Introduction Since June 2003 a daily gauge is generated at 1400 UTC when the majority of the manual gauge observations have been reported. The radar-gaugeBias adjustment of radar-based 3-hour precipitation accumulations Iwan Holleman Technical Report

  7. Climatology of extreme rainfall from rain gauges and weather radar

    E-Print Network [OSTI]

    Stoffelen, Ad

    by conventional rain gauge networks. A 10-year radar-based climatology of rainfall depths for durations of 15 minClimatology of extreme rainfall from rain gauges and weather radar Aart Overeem #12;Thesis:30 PM in the Aula #12;Aart Overeem Climatology of extreme rainfall from rain gauges and weather radar

  8. Monitoring Alpine Glaciers with ALOS SAR and Optical data Ph. Bolon(1)

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Monitoring Alpine Glaciers with ALOS SAR and Optical data Ph. Bolon(1) , E. Trouvé(1) , I. Pétillot ­ tania.landes@insa-strasbourg.fr Abstract The monitoring of temperate glacier activity is one interferometric SAR data and high resolution panchromatic stereoscopic data to monitor moving temperate glaciers

  9. ASSESSMENT OF RESPONSE TIME OF SAR PROBE Franois GALLEE, Gaetan GUEVEL, Christian PERSON

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ASSESSMENT OF RESPONSE TIME OF SAR PROBE François GALLEE, Gaetan GUEVEL, Christian PERSON Institut domain with a TDMA frame of 4.615ms divided in 8 time slot of 577µs. Then from a CW calibration and a mean value measurement with a high sensitivity multimeter, it is possible to measure the SAR (Specific

  10. USAGE OF RADARS FOR WIND ENERGY APPICATIONS Determine the benefit of using radar observations for wind energy applications by

    E-Print Network [OSTI]

    USAGE OF RADARS FOR WIND ENERGY APPICATIONS TASK: Determine the benefit of using radar observations for wind energy applications by analyzing i) the resolution effects and ii) sensitivity effects of weather radar systems. MOTIVATION: Wind energy applications strongly focus high-resolution wind observations

  11. published in JGR, 105, 21,781-21,794, 2000 Deformation and seismicity in the Coso geothermal

    E-Print Network [OSTI]

    published in JGR, 105, 21,781-21,794, 2000 Deformation and seismicity in the Coso geothermal area. Interferometric synthetic aperture radar (InSAR) data collected in the Coso geothermal area, eastern California with the production area of the Coso geothermal plant. The maximum subsidence rate in the peak of the anomaly is 3

  12. LETTER Earth Planets Space, 62, 875879, 2010 The Mw 7.9, 12 May 2008 Sichuan earthquake rupture measured by sub-pixel

    E-Print Network [OSTI]

    Klinger, Yann

    two major faults of the Long- men Shan thrust system, the Wenchuan and Beichuan faults (Fig. 1-band spaceborne Synthetic Aperture Radar (SAR) from the PALSAR sensor onboard Copyright c The Society of sight (i.e., slant range) and along track (i.e., azimuth) direc- tions of the sensor, we gain

  13. Im2Learn Manual The motivation for developing Im2Learn (Image to Learn) comes from academic, government

    E-Print Network [OSTI]

    Minsker, Barbara S.

    cover classification, map analysis, geo-spatial information systems (GIS), synthetic aperture radar (SAR, automobile industry, database retrieval, surveillance, and digital library. Band Selection Unsupervised de-noising and de-blurring in microarray data. Classification: Two and N-class classification

  14. Tape-Spring Rolling Hinges Alan M. Watt1

    E-Print Network [OSTI]

    Pellegrino, Sergio

    for solar array panels, synthetic aperture radars (SARs), booms, radiators and the like. Several successful design of a low cost, unlubricated, self-deploying, self-locking hinge whose properties can be easily-high power solar arrays, involve the use of stiff members connected by self-locking hinges. The design

  15. Retrieval of cloud properties using SCIAMACHY on ENVISAT

    E-Print Network [OSTI]

    Kuligowski, Bob

    ;2 AGENDA 1. Rationale 2. SCIAMACHY and its calibration 3. Algorithms 4. SCIMACHY cloud retrievals 5 Synthetic Aperture Radar (ASAR), operating at C-band, ASAR ensures continuity with the image mode (SAR;13 VICARIOUS CALIBRATION USING MERIS #12;14 MERIS on ENVISAT spacecraft /1.03.2002-present/ · Instrument bands

  16. 4674 IEEE TRANSACTIONS ON SIGNAL PROCESSING, VOL. 58, NO. 9, SEPTEMBER 2010 A Low Complexity Blind Estimator of Narrowband

    E-Print Network [OSTI]

    Langendoen, Koen

    a precisely calibrated array. The array manifold is then assumed to be unknown, and the estimation is referred signals (PPSs) are commonly used in synthetic aperture radar (SAR) imaging and radio communications Identifier 10.1109/TSP.2010.2050202 tion techniques in [6]­[12] assume that the array is perfectly calibrated

  17. Great Lakes NATIONALOCEAN

    E-Print Network [OSTI]

    -situ and modeled data, including marine and meteorological observations, buoy observations, water level gauge-line interactive retrieval of physical parameters such as surface temperature, ice cover, winds, and bottom depth such as synthetic aperture radar (SAR), scatterometer, and ocean color sensors are being develop

  18. Review of SAR for Packaging Report | Department of Energy

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

    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: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOrigin ofEnergy at Waste-to-Energy usingofRetrofitting DoorsReview of SAR for Packaging

  19. Microsoft Word - PeerReview_SAR.doc | Department of Energy

    Office of Environmental Management (EM)

    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 for4,645 3,625 1,006 492 742 33 111 1,613 122Commercial602 1,39732onMake Your NextHow EM AcronymsIQA memo10-6-08SAR.doc Microsoft

  20. Some non-precipitation radar echoes as observed by CPS-9 radar

    E-Print Network [OSTI]

    Luckenbach, Guenther Edward

    1959-01-01T23:59:59.000Z

    . Solar Signal Lightning Metallic Objects Anomalous Propagation 23 23 25 25 1. 23 July 1958 5 August 1958 7 August 1958 13 August 1958 5. 8 September 1958. 9 September 1958 Cold Front 32 32 41 41 47 10. Lightning Layers - Radiosonde... artificially produced boundaries of temperature~ humidity, and turbulence but failed to detect angels on 3. 2 and 1. 25 cm radar. No means independent of the radar for measuring the inhomogenities was employed. In 1948, Baldwin [ 2 ] suggested that angels...

  1. Aperture calculation of the Pierre Auger Observatory surface detector

    SciTech Connect (OSTI)

    Allard, D.; Allekotte, I.; Armengaud, E.; Aublin, J.; Bertou, Xavier; Chou, A.; Ghia, P.L.; Gomez Berisso, M.; Hamilton, J.C.; Lhenry-Yvon, I.; Medina, C.; Navarra, G.; Parizot, E.; Tripathi, A.

    2005-08-01T23:59:59.000Z

    We determine the instantaneous aperture and integrated exposure of the surface detector of the Pierre Auger Observatory, taking into account the trigger efficiency as a function of the energy, arrival direction (with zenith angle lower than 60 degrees) and nature of the primary cosmic-ray. We make use of the so-called Lateral Trigger Probability function (or LTP) associated with an extensive air shower, which summarizes all the relevant information about the physics of the shower, the water tank Cherenkov detector, and the triggers.

  2. Coded aperture imaging with self-supporting uniformly redundant arrays

    DOE Patents [OSTI]

    Fenimore, Edward E. (Los Alamos, NM)

    1983-01-01T23:59:59.000Z

    A self-supporting uniformly redundant array pattern for coded aperture imaging. The present invention utilizes holes which are an integer times smaller in each direction than holes in conventional URA patterns. A balance correlation function is generated where holes are represented by 1's, nonholes are represented by -1's, and supporting area is represented by 0's. The self-supporting array can be used for low energy applications where substrates would greatly reduce throughput. The balance correlation response function for the self-supporting array pattern provides an accurate representation of the source of nonfocusable radiation.

  3. Doppler Radar Wind Profiles Iwan Holleman

    E-Print Network [OSTI]

    Stoffelen, Ad

    ). The potential impact of a network of boundary layer wind profilers and sodars for mesoscale wind analysisDoppler Radar Wind Profiles Iwan Holleman Scientific Report, KNMI WR-2003-02, 2003 #12;2 #12 Strategy 18 3 Methods for Wind Profile Retrieval 25 3.1 Radial Velocity from Local Wind Model 25 3

  4. Design and calibration of the PHARUS polarimetric airborne SAR

    SciTech Connect (OSTI)

    Snoeij, P. [Delft Univ. of Technology, Delft (Netherlands); Hoogeboom, P.; Koomen, P.J. [and others

    1996-11-01T23:59:59.000Z

    The PHARUS system uses a phased array antenna with solid state amplifiers. The project consisted of two phases, a definition phase and a realization phase. The definition phase consisted of the actual realization of a SAR research system called PHARS, which made its first successful testflight in November 1990. The research system is based on the concept of a wide beamwidth antenna, rigidly fixed to the aircraft. Pulse compression and a high PRF ensure sufficient sensitivity in this system, which is equipped with a 160 Watt peak pulse power solid state transmitter. The processing is done off-line. In the realization phase the polarimetric PHARUS system has been developed. The design is based on the experience gained with the PHARS system. The system uses a phased array with dual polarized patch radiators and is equipped with solid state amplifiers. This paper will give an overview of the PHARUS design and operational use. Apart from the use as an advanced polarimetric airborne SAR, there is the perspective of using PHARUS as a demonstrator for ESA`s future ASAR system. 2 refs., 2 figs., 1 tab.

  5. Apparatus and method for deterministic control of surface figure during full aperture polishing

    DOE Patents [OSTI]

    Suratwala, Tayyab Ishaq; Feit, Michael Dennis; Steele, William Augustus

    2013-11-19T23:59:59.000Z

    A polishing system configured to polish a lap includes a lap configured to contact a workpiece for polishing the workpiece; and a septum configured to contact the lap. The septum has an aperture formed therein. The radius of the aperture and radius the workpiece are substantially the same. The aperture and the workpiece have centers disposed at substantially the same radial distance from a center of the lap. The aperture is disposed along a first radial direction from the center of the lap, and the workpiece is disposed along a second radial direction from the center of the lap. The first and second radial directions may be opposite directions.

  6. High Resolution Backside Imaging and Thermography using a Numerical Aperture Increasing Lens

    E-Print Network [OSTI]

    High Resolution Backside Imaging and Thermography using a Numerical Aperture Increasing Lens M. S, representing the highest resolution subsurface thermography to date. Keywords: thermal imaging, high

  7. Design guidelines for SAR digital receiver/exciter boards.

    SciTech Connect (OSTI)

    Dudley, Peter A.

    2009-08-01T23:59:59.000Z

    High resolution radar systems generally require combining fast analog to digital converters and digital to analog converters with very high performance digital signal processing logic. These mixed analog and digital printed circuit boards present special challenges with respect to electromagnetic interference. This document first describes the mechanisms of interference on such boards then follows up with a discussion of prevention techniques and finally provides a checklist for designers to help avoid common mistakes.

  8. Aperture-based antihydrogen gravity experiment: Parallel plate geometry

    SciTech Connect (OSTI)

    Rocha, J. R.; Hedlof, R. M.; Ordonez, C. A. [Department of Physics, University of North Texas, Denton, Texas 76203 (United States)] [Department of Physics, University of North Texas, Denton, Texas 76203 (United States)

    2013-10-15T23:59:59.000Z

    An analytical model and a Monte Carlo simulation are presented of an experiment that could be used to determine the direction of the acceleration of antihydrogen due to gravity. The experiment would rely on methods developed by existing antihydrogen research collaborations. The configuration consists of two circular, parallel plates that have an axis of symmetry directed away from the center of the earth. The plates are separated by a small vertical distance, and include one or more pairs of circular barriers that protrude from the upper and lower plates, thereby forming an aperture between the plates. Antihydrogen annihilations that occur just beyond each barrier, within a “shadow” region, are asymmetric on the upper plate relative to the lower plate. The probability for such annihilations is determined for a point, line and spheroidal source of antihydrogen. The production of 100,000 antiatoms is predicted to be necessary for the aperture-based experiment to indicate the direction of free fall acceleration of antimatter, provided that antihydrogen is produced within a sufficiently small antiproton plasma at a temperature of 4 K.

  9. Development of a Drillrod/Telemetry Radar

    SciTech Connect (OSTI)

    Raton Technology Research, Inc.

    1999-11-12T23:59:59.000Z

    Efficient extraction of deeply buried natural resources is dependent upon accurate geologic models. The model becomes the basis for developing plans for extraction of the resource. Geoscientists working in geothermal and hydrocarbon recovery have a great deal in common with fellow geoscientists working in the mining industry. They appreciate the intractable problem of increasing the depth of investigation to tens of meters from the wellbore. The goal of this project was to develop a borehole radar tool to acquire data within tens of meters from the wellbore. For geothermal and hydrocarbon applications, the tool was to acquire data for mapping fractures surrounding the wellbore. In mining of coal, the radar acquires data for determining coal seam thickness and detecting geologic anomalies ahead of mining.

  10. 3-D airborne ultrasound synthetic aperture imaging based on capacitive micromachined ultrasonic transducers

    E-Print Network [OSTI]

    Khuri-Yakub, Butrus T. "Pierre"

    3-D airborne ultrasound synthetic aperture imaging based on capacitive micromachined ultrasonic was implemented by mechanical scanning a co-located transmitter and receiver using the classic synthetic aperture, silicone rubber, and foam plastics, in an attempt to overcome bad mechanical impedance matching between

  11. Aperture synthesis of time-limited X waves and analysis of their propagation characteristics

    E-Print Network [OSTI]

    Lu, Jian-yu

    of Engineering Physics and Mathematics, Faculty of Engineering Cairo University, Giza, Egypt Ioannis M. Besieris. Also, the possibility of using a finite-time excitation of a dynamic aperture to generate a finite-energy-time aperture. This confirms the fact that time windowing the infinite energy X-wave excitation is a viable

  12. Super-resolution in incoherent optical imaging using synthetic aperture with Fresnel elements

    E-Print Network [OSTI]

    Rosen, Joseph

    Super-resolution in incoherent optical imaging using synthetic aperture with Fresnel elements Barak the Rayleigh limit of the system is obtained by tiling digitally several Fresnel holographic elements into a complete Fresnel hologram of the observed object. Each element is acquired by the limited-aperture system

  13. Development of a large aperture Nb3Sn racetrack quadrupolemagnet

    SciTech Connect (OSTI)

    Ferracin, Paolo; Bartlett, Scott E.; Caspi, Shlomo; Dietderich,Daniel R.; Gourlay, Steven A.; Hannaford, Charles R.; Hafalia, AurelioR.; Lietzke, Alan F.; Mattafirri, Sara; McInturff, Alfred D.; Nyman,Mark; Sabbi, Gianluca

    2005-04-14T23:59:59.000Z

    The U.S. LHC Accelerator Research Program (LARP), a collaboration between BNL, FNAL, LBNL, and SLAC, has among its major objectives the development of advanced magnet technology for an LHC luminosity upgrade. The LBNL Superconducting Magnet Group supports this program with a broad effort involving design studies, Nb{sub 3}Sn conductor development, mechanical models, and basic prototypes. This paper describes the development of a large aperture Nb{sub 3}Sn racetrack quadrupole magnet using four racetrack coils from the LBNL Subscale Magnet (SM) Program. The magnet provides a gradient of 95 T/m in a 110 mm bore, with a peak field in the conductor of 11.2 T. The coils are prestressed by a mechanical structure based on a pre-tensioned aluminum shell, and axially supported with aluminum rods. The mechanical behavior has been monitored with strain gauges and the magnetic field has been measured. Results of the test are reported and analyzed.

  14. Hydraulic transmissivity and heat exchange efficiency of open fractures: a model based on lowpass filtered apertures

    E-Print Network [OSTI]

    Neuville, Amélie; Schmittbuhl, Jean; 10.1111/j.1365-246X.2011.05126.x

    2011-01-01T23:59:59.000Z

    Natural open joints in rocks commonly present multi-scale self-affine apertures. This geometrical complexity affects fluid transport and heat exchange between the flow- ing fluid and the surrounding rock. In particular, long range correlations of self-affine apertures induce strong channeling of the flow which influences both mass and heat advection. A key question is to find a geometrical model of the complex aperture that describes at best the macroscopic properties (hydraulic conductivity, heat exchange) with the smallest number of parameters. Solving numerically the Stokes and heat equa- tions with a lubrication approximation, we show that a low pass filtering of the aperture geometry provides efficient estimates of the effective hydraulic and thermal properties (apertures). A detailed study of the influence of the bandwidth of the lowpass filtering on these transport properties is also performed. For instance, keeping the information of amplitude only of the largest Fourier length scales allows us to rea...

  15. Digitized dual wavelength radar data from a Texas thunderstorm

    E-Print Network [OSTI]

    Radlein, Robin Ann

    1977-01-01T23:59:59.000Z

    DIGITIZED DUAL WAVL'LENGTH RADAR DATA FROM A TEXAS THUNDERSTORM A Thesis ROBIN ANN RADLEIN Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree ol MASTER OF SCIENCE December 1977... Wavelength Radar Data from a Texas Thunderstorm. (December 1977) Robin Ann Radlein~ B. S , Texas ASN University Chairman of Advisory Committee: Dr Vance Noyer Nulti-tilt digitized dual wavelength radar data collected during a Texas thunderstorm were...

  16. Cleavage of the SARS Coronavirus Spike Glycoprotein by Airway Proteases Enhances Virus Entry into Human

    E-Print Network [OSTI]

    Boyer, Edmond

    have direct implications for the cell entry mechanism of SARS-CoV along the respiratory system and the susceptibility of a recombinant native full-length S-protein trimer (triSpike) of the severe acute respiratory

  17. SAR Assessment and Analysis of Cumulative Body Exposure to Multi Transmitters from a Mobile Phone

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    against possible negative health effects of radiofrequency electromagnetic radiation. Basic restriction evaluated ones from each transmitter separately. Index Terms -- SAR, Multiple exposure, Radiofrequency I Commission on Non Ionizing Radiation Protection (ICNIRP) [1] and the Institute of Electronics and Electrical

  18. Calibration Techniques for Time-Interleaved SAR A/D Converters

    E-Print Network [OSTI]

    Stepanovic, Dusan Vlastimir

    2012-01-01T23:59:59.000Z

    major obstacle to an energy-efficient design in the proposeda compact and energy-efficient design of the SAR ADCs. •yield a very energy-efficient ADC design in 10 GHz sampling

  19. Low-power high-performance SAR ADC with redundancy and digital background calibration

    E-Print Network [OSTI]

    Chang, Albert Hsu Ting

    2013-01-01T23:59:59.000Z

    As technology scales, the improved speed and energy eciency make the successive- approximation-register (SAR) architecture an attractive alternative for applications that require high-speed and high-accuracy analog-to-digital ...

  20. Raindrop size distributions and radar reflectivity-rain rate relationships for radar hydrology Hydrology and Earth System Sciences, 5(4), 615627 (2001) EGS

    E-Print Network [OSTI]

    Boyer, Edmond

    Raindrop size distributions and radar reflectivity-rain rate relationships for radar hydrology 615 Hydrology and Earth System Sciences, 5(4), 615­627 (2001) © EGS Raindrop size distributions and radar reflectivity­rain rate relationships for radar hydrology* Remko Uijlenhoet1 Sub-department Water Resources

  1. Applications of Radar Interferometry to Detect Surface Deformation...

    Open Energy Info (EERE)

    Valley in Southern California Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Paper: Applications of Radar Interferometry to Detect Surface...

  2. NNSA Completes its Critical Radar Arming and Fuzing Test for...

    National Nuclear Security Administration (NNSA)

    its Critical Radar Arming and Fuzing Test for the W88 ALT 370 | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile...

  3. Ocean Intelligence and the Role of Spaceborne SAR Data in the Littoral Zone

    E-Print Network [OSTI]

    1 © CSA Ocean Intelligence and the Role of Spaceborne SAR Data in the Littoral Zone Gordon Staples tasking (12 - 24 hours routine) ­ faster data processing ­ data encryption Calibrated data #12;7 RADARSAT 4 Wide 20° - 45° 150 km 25 x 28 m 1 x 4 ScanSAR Narrow 20° - 46° 300 km 50 x 50 m 2 x 2 Selective

  4. Design and Development of Dual Polarized, Stacked Patch Antenna Element for S-Band Dual-Pol Weather Radar Array

    E-Print Network [OSTI]

    Bhardwaj, Shubhendu

    2012-01-01T23:59:59.000Z

    in Weather Detection . . . . . . . . . . . . . . . . . .for S-Band Weather Radar . . . . . . . . . . . . . Dual-polpatterns of polarimetric weather radars,” Journal of

  5. ASAP progress and expenditure report for the month of February 1--29, 1996

    SciTech Connect (OSTI)

    Twogood, R.E.; Brase, J.M.; Chambers, D.H.; Mantrom, D.M.; Miller, M.G.; Newman, M.J.; Robey, H.F.; Vigars, M.

    1996-03-20T23:59:59.000Z

    This is the ASAP progress and expenditure report for the month of February, 1996. The individual projects` report includes the sponsoring organization, the project identification, the principal investigator, long term objectives, short term objectives, accomplishments this reporting period, identification of issues or concerns, project budget estimate for the fiscal year, and monthly actual and year to date expenditures. The research project concerns a joint US/UK program to develop a high-priority radar system based on real aperture and synthetic aperature radar. Topics being researched include airborne RAR/SAR; radar data processor; ground-based SAR signal processing workstation; static airborne radar; radar field experiments; data analysis and detection theory; program management; modeling and analysis; UCSB wave tank; stratified wave tank; and experiments in a thermo-stratified tank at the Institute of Applied Physics, Russia.

  6. Is a Curved Flight Path in SAR Better than a Straight One?

    E-Print Network [OSTI]

    2013-07-23T23:59:59.000Z

    the radar is not directed but has other applications, like thermoacoustic ... as well, and in particular in thermoacoustic tomography with constant acoustic speed;.

  7. Particle-in-Cell Modeling of Magnetized Argon Plasma Flow Through Small Mechanical Apertures

    SciTech Connect (OSTI)

    Adam B. Sefkow and Samuel A. Cohen

    2009-04-09T23:59:59.000Z

    Motivated by observations of supersonic argon-ion flow generated by linear helicon-heated plasma devices, a three-dimensional particle-in-cell (PIC) code is used to study whether stationary electrostatic layers form near mechanical apertures intersecting the flow of magnetized plasma. By self-consistently evaluating the temporal evolution of the plasma in the vicinity of the aperture, the PIC simulations characterize the roles of the imposed aperture and applied magnetic field on ion acceleration. The PIC model includes ionization of a background neutral-argon population by thermal and superthermal electrons, the latter found upstream of the aperture. Near the aperture, a transition from a collisional to a collisionless regime occurs. Perturbations of density and potential, with mm wavelengths and consistent with ion acoustic waves, propagate axially. An ion acceleration region of length ~ 200?300 ?D,e forms at the location of the aperture and is found to be an electrostatic double layer, with axially-separated regions of net positive and negative charge. Reducing the aperture diameter or increasing its length increases the double layer strength.

  8. Aperture-Tolerant, Chemical-Based Methods to Reduce Channeling

    SciTech Connect (OSTI)

    Randall S. Seright

    2007-09-30T23:59:59.000Z

    This final technical progress report describes work performed from October 1, 2004, through May 16, 2007, for the project, 'Aperture-Tolerant, Chemical-Based Methods to Reduce Channeling'. We explored the potential of pore-filling gels for reducing excess water production from both fractured and unfractured production wells. Several gel formulations were identified that met the requirements--i.e., providing water residual resistance factors greater than 2,000 and ultimate oil residual resistance factors (F{sub rro}) of 2 or less. Significant oil throughput was required to achieve low F{sub rro} values, suggesting that gelant penetration into porous rock must be small (a few feet or less) for existing pore-filling gels to provide effective disproportionate permeability reduction. Compared with adsorbed polymers and weak gels, strong pore-filling gels can provide greater reliability and behavior that is insensitive to the initial rock permeability. Guidance is provided on where relative-permeability-modification/disproportionate-permeability-reduction treatments can be successfully applied for use in either oil or gas production wells. When properly designed and executed, these treatments can be successfully applied to a limited range of oilfield excessive-water-production problems. We examined whether gel rheology can explain behavior during extrusion through fractures. The rheology behavior of the gels tested showed a strong parallel to the results obtained from previous gel extrusion experiments. However, for a given aperture (fracture width or plate-plate separation), the pressure gradients measured during the gel extrusion experiments were much higher than anticipated from rheology measurements. Extensive experiments established that wall slip and first normal stress difference were not responsible for the pressure gradient discrepancy. To explain the discrepancy, we noted that the aperture for gel flow (for mobile gel wormholing through concentrated immobile gel within the fracture) was much narrower than the width of the fracture. The potential of various approaches were investigated for improving sweep in parts of the Daqing Oil Field that have been EOR targets. Possibilities included (1) gel treatments that are directed at channeling through fractures, (2) colloidal dispersion gels, (3) reduced polymer degradation, (4) more viscous polymer solutions, and (5) foams and other methods. Fractures were present in a number of Daqing wells (both injectors and producers). Because the fractures were narrow far from the wellbore, severe channeling did not occur. On the contrary, fractures near the wellbore aided reservoir sweep. In the February 2006 issue of the Journal of Petroleum Technology, a 'Distinguished-Author-Series' paper claimed that a process using aqueous colloidal dispersion gels (CDG gels) performed superior to polymer flooding. Unfortunately, this claim is misleading and generally incorrect. Colloidal dispersion gels, in their present state of technological development, should not be advocated as an improvement to, or substitute for, polymer flooding.

  9. MEJORAMIENTO DE ONDAS INTERNAS EN IMGENES SAR USANDO, EN FORMA COMBINADA, LAS TRANSFORMADAS RADON Y WAVELETS (1-D)

    E-Print Network [OSTI]

    Hernández-Walls, Rafael

    distribución especial del oleaje y de las ondas internas, cuando estas están presentes en una imagen SAR. En

  10. Natural phenomena risk analysis - an approach for the tritium facilities 5480.23 SAR natural phenomena hazards accident analysis

    SciTech Connect (OSTI)

    Cappucci, A.J. Jr.; Joshi, J.R.; Long, T.A.; Taylor, R.P.

    1997-07-01T23:59:59.000Z

    A Tritium Facilities (TF) Safety Analysis Report (SAR) has been developed which is compliant with DOE Order 5480.23. The 5480.23 SAR upgrades and integrates the safety documentation for the TF into a single SAR for all of the tritium processing buildings. As part of the TF SAR effort, natural phenomena hazards (NPH) were analyzed. A cost effective strategy was developed using a team approach to take advantage of limited resources and budgets. During development of the Hazard and Accident Analysis for the 5480.23 SAR, a strategy was required to allow maximum use of existing analysis and to develop a cost effective graded approach for any new analysis in identifying and analyzing the bounding accidents for the TF. This approach was used to effectively identify and analyze NPH for the TF. The first part of the strategy consisted of evaluating the current SAR for the RTF to determine what NPH analysis could be used in the new combined 5480.23 SAR. The second part was to develop a method for identifying and analyzing NPH events for the older facilities which took advantage of engineering judgment, was cost effective, and followed a graded approach. The second part was especially challenging because of the lack of documented existing analysis considered adequate for the 5480.23 SAR and a limited budget for SAR development and preparation. This paper addresses the strategy for the older facilities.

  11. Comments on momentum aperture of 100 GeV/n Au runs in RHIC

    SciTech Connect (OSTI)

    Zhang, S.Y.

    2011-11-01T23:59:59.000Z

    In RHIC 2010 100 GeV/n Au run, the momentum aperture has been an issue in the re-bucketing and the beam intensity lifetime in store. Both Blue and Yellow beams with comparable storage RF voltage and peak current have suffered more beam loss than in Run 2007. In this note, some comments are made for the momentum aperture of the lattices used from the Au runs in 2007, 2008 and 2010. From the wigglings and the beam decays of each lattice, information regarding the machine momentum aperture is presented. Several directions in further improvement are discussed.

  12. 32nd Conf. Radar Meteorology Albuquerque, NM, 2005

    E-Print Network [OSTI]

    Xue, Ming

    32nd Conf. Radar Meteorology Albuquerque, NM, 2005 J1J.4 MULTIPLE DOPPLER WIND ANALYSIS and smoothness constraints by incorporating them into a cost function yielding the 3-D wind. In this study, this 3DVAR analysis method is adapted to perform multiple Doppler wind analysis for CASA radars, together

  13. Radar-cross-section reduction of wind turbines. part 1.

    SciTech Connect (OSTI)

    Brock, Billy C.; Loui, Hung; McDonald, Jacob J.; Paquette, Joshua A.; Calkins, David A.; Miller, William K.; Allen, Steven E.; Clem, Paul Gilbert; Patitz, Ward E.

    2012-03-05T23:59:59.000Z

    In recent years, increasing deployment of large wind-turbine farms has become an issue of growing concern for the radar community. The large radar cross section (RCS) presented by wind turbines interferes with radar operation, and the Doppler shift caused by blade rotation causes problems identifying and tracking moving targets. Each new wind-turbine farm installation must be carefully evaluated for potential disruption of radar operation for air defense, air traffic control, weather sensing, and other applications. Several approaches currently exist to minimize conflict between wind-turbine farms and radar installations, including procedural adjustments, radar upgrades, and proper choice of low-impact wind-farm sites, but each has problems with limited effectiveness or prohibitive cost. An alternative approach, heretofore not technically feasible, is to reduce the RCS of wind turbines to the extent that they can be installed near existing radar installations. This report summarizes efforts to reduce wind-turbine RCS, with a particular emphasis on the blades. The report begins with a survey of the wind-turbine RCS-reduction literature to establish a baseline for comparison. The following topics are then addressed: electromagnetic model development and validation, novel material development, integration into wind-turbine fabrication processes, integrated-absorber design, and wind-turbine RCS modeling. Related topics of interest, including alternative mitigation techniques (procedural, at-the-radar, etc.), an introduction to RCS and electromagnetic scattering, and RCS-reduction modeling techniques, can be found in a previous report.

  14. Greenland snow accumulation estimates from satellite radar scatterometer data

    E-Print Network [OSTI]

    Long, David G.

    Greenland snow accumulation estimates from satellite radar scatterometer data Mark R. Drinkwater accumulation on the Greenland ice sheet. Microwave radar backscatter images of Greenland are derived using (or decrease) in net snow accumulation on the polar ice caps. The net mass balance of the Greenland

  15. Weather Radar Control System Seidu Ibrahim; Advisor: Eric J. Knapp

    E-Print Network [OSTI]

    Mountziaris, T. J.

    Weather Radar Control System Seidu Ibrahim; Advisor: Eric J. Knapp Dept. of Electrical and Computer Engineering University of Massachusetts, Amherst Abstract Weather radar is an important part of the national infrastructure that is used in producing forecasts and issuing hazardous weather warnings. Traditional weather

  16. Ultrawideband radar clutter measurements of forested terrain, 1991--1992

    SciTech Connect (OSTI)

    Sheen, D.M.; Severtsen, R.H.; Prince, J.M.; Davis, K.C.; Collins, H.D.

    1993-06-01T23:59:59.000Z

    The ultrawideband (UWB) radar clutter measurements project was conducted to provide radar clutter data for new ultrawideband radar systems which are currently under development. A particular goal of this project is to determine if conventional narrow band clutter data may be extrapolated to the UWB case. This report documents measurements conducted in 1991 and additional measurements conducted in 1992. The original project consisted of clutter measurements of forested terrain in the Olympic National Forest near Sequim, WA. The impulse radar system used a 30 kW peak impulse source with a 2 Gigasample/second digitizer to form a UHF (300--1000 MHz) ultrawideband impulse radar system. Additional measurements were conducted in parallel using a Systems Planning Corporation (SPC) step-chirp radar system. This system utilized pulse widths of 1330 nanoseconds over a bandwidth of 300--1000 MHz to obtain similar resolution to the impulse system. Due to the slow digitizer data throughput in the impulse radar system, data collection rates were significantly higher using the step-chirp system. Additional forest clutter measurements were undertaken in 1992 to increase the amount of data available, and especially to increase the amount of data from the impulse radar system.

  17. Radiation thermometer size-of-source effect testing using aperture

    SciTech Connect (OSTI)

    Liebmann, F.; Kolat, T. [Fluke Corporation, 799 E Utah Valley Dr., American Fork, Utah, USA, 84003 (United States)] [Fluke Corporation, 799 E Utah Valley Dr., American Fork, Utah, USA, 84003 (United States)

    2013-09-11T23:59:59.000Z

    Size-of-source effect is an important attribute of any radiation thermometer. The effects of this attribute may be quantified in a number of different ways to include field-of-view, distance ratio, or size-of-source effect. These parameters provide needed information for the user of a radiation thermometer, as they aid in determining whether the measured object is large enough for adequate radiation thermometry measurement. Just as important, these parameters provide needed information for calibration. This information helps to determine calibration geometry, and it is needed for calibration uncertainty determination. For determination of size-of-source effect, there are a limited number of test methods furnished by the standards available today. The test methods available may be cumbersome to perform due to the cost of the required equipment and the time needed to set-up and perform the test. Other methods have been proposed. This paper discusses one such method. This method uses a circular aperture such as that used in radiation thermometer calibration. It describes the method both theoretically and mechanically. It then discusses testing done to verify this method comparing the results to those obtained while performing steps in current standards. Finally, based on this testing, the basis for a new standard test method is presented.

  18. LAGOVirtual: A Collaborative Environment for the Large Aperture GRB Observatory

    E-Print Network [OSTI]

    R. Camacho; R. Chacon; G. Diaz; C. Guada; V. Hamar; H. Hoeger; A. Melfo; L. A. Nunez; Y. Perez; C. Quintero; M. Rosales; R. Torrens; the LAGO Collaboration

    2009-12-12T23:59:59.000Z

    We present the LAGOVirtual Project: an ongoing project to develop platform to collaborate in the Large Aperture GRB Observatory (LAGO). This continental-wide observatory is devised to detect high energy (around 100 GeV) component of Gamma Ray Bursts, by using the single particle technique in arrays of Water Cherenkov Detectors (WCD) at high mountain sites (Chacaltaya, Bolivia, 5300 m a.s.l., Pico Espejo, Venezuela, 4750 m a.s.l., Sierra Negra, Mexico, 4650 m a.s.l). This platform will allow LAGO collaboration to share data, and computer resources through its different sites. This environment has the possibility to generate synthetic data by simulating the showers through AIRES application and to store/preserve distributed data files collected by the WCD at the LAGO sites. The present article concerns the implementation of a prototype of LAGO-DR adapting DSpace, with a hierarchical structure (i.e. country, institution, followed by collections that contain the metadata and data files), for the captured/simulated data. This structure was generated by using the community, sub-community, collection, item model; available at the DSpace software. Each member institution-country of the project has the appropriate permissions on the system to publish information (descriptive metadata and associated data files). The platform can also associate multiple files to each item of data (data from the instruments, graphics, postprocessed-data, etc.).

  19. LAGOVirtual: A Collaborative Environment for the Large Aperture GRB Observatory

    E-Print Network [OSTI]

    Camacho, R; Diaz, G; Guada, C; Hamar, V; Hoeger, H; Melfo, A; Nunez, L A; Perez, Y; Quintero, C; Rosales, M; Torrens, R

    2009-01-01T23:59:59.000Z

    We present the LAGOVirtual Project: an ongoing project to develop platform to collaborate in the Large Aperture GRB Observatory (LAGO). This continental-wide observatory is devised to detect high energy (around 100 GeV) component of Gamma Ray Bursts, by using the single particle technique in arrays of Water Cherenkov Detectors (WCD) at high mountain sites (Chacaltaya, Bolivia, 5300 m a.s.l., Pico Espejo, Venezuela, 4750 m a.s.l., Sierra Negra, Mexico, 4650 m a.s.l). This platform will allow LAGO collaboration to share data, and computer resources through its different sites. This environment has the possibility to generate synthetic data by simulating the showers through AIRES application and to store/preserve distributed data files collected by the WCD at the LAGO sites. The present article concerns the implementation of a prototype of LAGO-DR adapting DSpace, with a hierarchical structure (i.e. country, institution, followed by collections that contain the metadata and data files), for the captured/simulate...

  20. advanced technology large-aperture: Topics by E-print Network

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

    The Large Aperture GRB Observatory (LAGO) is aiming at the detection of the high energy (around 100 GeV) component of Gamma Ray Bursts, using the single particle technique in...

  1. Synthetic Aperture Sonar Imaging via One-Way Wave Quyen Huynh

    E-Print Network [OSTI]

    produces a Naval Surface Warfare Center - Panama City FL, research partially supported by the US Office in the phase of the real aperture data. We adopt the Stop and Go model; a point source radiates at time t = 0

  2. Impulse radar with swept range gate

    DOE Patents [OSTI]

    McEwan, Thomas E. (Livermore, CA)

    1998-09-08T23:59:59.000Z

    A radar range finder and hidden object locator is based on ultra-wide band radar with a high resolution swept range gate. The device generates an equivalent time amplitude scan with a typical range of 4 inches to 20 feet, and an analog range resolution as limited by a jitter of on the order of 0.01 inches. A differential sampling receiver is employed to effectively eliminate ringing and other aberrations induced in the receiver by the near proximity of the transmit antenna (10), so a background subtraction is not needed, simplifying the circuitry while improving performance. Techniques are used to reduce clutter in the receive signal, such as decoupling the receive (24) and transmit cavities (22) by placing a space between them, using conductive or radiative damping elements on the cavities, and using terminating plates on the sides of the openings. The antennas can be arranged in a side-by-side parallel spaced apart configuration or in a coplanar opposed configuration which significantly reduces main bang coupling.

  3. Impulse radar with swept range gate

    DOE Patents [OSTI]

    McEwan, T.E.

    1998-09-08T23:59:59.000Z

    A radar range finder and hidden object locator is based on ultra-wide band radar with a high resolution swept range gate. The device generates an equivalent time amplitude scan with a typical range of 4 inches to 20 feet, and an analog range resolution as limited by a jitter of on the order of 0.01 inches. A differential sampling receiver is employed to effectively eliminate ringing and other aberrations induced in the receiver by the near proximity of the transmit antenna, so a background subtraction is not needed, simplifying the circuitry while improving performance. Techniques are used to reduce clutter in the receive signal, such as decoupling the receive and transmit cavities by placing a space between them, using conductive or radiative damping elements on the cavities, and using terminating plates on the sides of the openings. The antennas can be arranged in a side-by-side parallel spaced apart configuration or in a coplanar opposed configuration which significantly reduces main bang coupling. 25 figs.

  4. Assembly flow simulation of a radar

    SciTech Connect (OSTI)

    Rutherford, W.C.; Biggs, P.M.

    1993-10-01T23:59:59.000Z

    A discrete event simulation model has been developed to predict the assembly flow time of a new radar product. The simulation was the key tool employed to identify flow constraints. The radar, production facility, and equipment complement were designed, arranged, and selected to provide the most manufacturable assembly possible. A goal was to reduce the assembly and testing cycle time from twenty-six weeks to six weeks. A computer software simulation package (SLAM II) was utilized as the foundation a for simulating the assembly flow time. FORTRAN subroutines were incorporated into the software to deal with unique flow circumstances that were not accommodated by the software. Detailed information relating to the assembly operations was provided by a team selected from the engineering, manufacturing management, inspection, and production assembly staff. The simulation verified that it would be possible to achieve the cycle time goal of six weeks. Equipment and manpower constraints were identified during the simulation process and adjusted as required to achieve the flow with a given monthly production requirement. The simulation is being maintained as a planning tool to be used to identify constraints in the event that monthly output is increased. ``What-if`` studies have been conducted to identify the cost of reducing constraints caused by increases in output requirement.

  5. A multichannel, real-time MRI RF power monitor for independent SAR determination

    SciTech Connect (OSTI)

    El-Sharkawy, AbdEl-Monem M.; Qian Di; Bottomley, Paul A.; Edelstein, William A. [Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins, University School of Medicine, Baltimore, Maryland 21287 (United States); Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins, University School of Medicine, Baltimore, Maryland 21287 (United States) and Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, Maryland 21287 (United States); Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins, University School of Medicine, Baltimore, Maryland 21287 (United States)

    2012-05-15T23:59:59.000Z

    Purpose: Accurate measurements of the RF power delivered during clinical MRI are essential for safety and regulatory compliance, avoiding inappropriate restrictions on clinical MRI sequences, and for testing the MRI safety of peripheral and interventional devices at known RF exposure levels. The goal is to make independent RF power measurements to test the accuracy of scanner-reported specific absorption rate (SAR) over the extraordinary range of operating conditions routinely encountered in MRI. Methods: A six channel, high dynamic range, real-time power profiling system was designed and built for monitoring power delivery during MRI up to 440 MHz. The system was calibrated and used in two 3 T scanners to measure power applied to human subjects during MRI scans. The results were compared with the scanner-reported SAR. Results: The new power measurement system has highly linear performance over a 90 dB dynamic range and a wide range of MRI duty cycles. It has about 0.1 dB insertion loss that does not interfere with scanner operation. The measurements of whole-body SAR in volunteers showed that scanner-reported SAR was significantly overestimated by up to about 2.2 fold. Conclusions: The new power monitor system can accurately and independently measure RF power deposition over the wide range of conditions routinely encountered during MRI. Scanner-reported SAR values are not appropriate for setting exposure limits during device or pulse sequence testing.

  6. Spotlight SAR interferometry for terrain elevation mapping and interferometric change detection

    SciTech Connect (OSTI)

    Eichel, P.H.; Ghiglia, D.C.; Jakowatz, C.V. Jr. [and others

    1996-02-01T23:59:59.000Z

    In this report, we employ an approach quite different from any previous work; we show that a new methodology leads to a simpler and clearer understanding of the fundamental principles of SAR interferometry. This methodology also allows implementation of an important collection mode that has not been demonstrated to date. Specifically, we introduce the following six new concepts for the processing of interferometric SAR (INSAR) data: (1) processing using spotlight mode SAR imaging (allowing ultra-high resolution), as opposed to conventional strip-mapping techniques; (2) derivation of the collection geometry constraints required to avoid decorrelation effects in two-pass INSAR; (3) derivation of maximum likelihood estimators for phase difference and the change parameter employed in interferometric change detection (ICD); (4) processing for the two-pass case wherein the platform ground tracks make a large crossing angle; (5) a robust least-squares method for two-dimensional phase unwrapping formulated as a solution to Poisson`s equation, instead of using traditional path-following techniques; and (6) the existence of a simple linear scale factor that relates phase differences between two SAR images to terrain height. We show both theoretical analysis, as well as numerous examples that employ real SAR collections to demonstrate the innovations listed above.

  7. Calibration of the groundbased radars during CLARE'98 Robin J. Hogan

    E-Print Network [OSTI]

    Hogan, Robin

    Calibration of the ground­based radars during CLARE'98 Robin J. Hogan Department of Meteorology. The approach used to calibrate the radars is to start with the absolute calibration provided by the Rabelais radar in Rayleigh­scattering light rain or cloud. Finally the W­band radars are calibrated

  8. A 10-year radar-based climatology of rainfall Aart Overeem, Iwan Holleman, Adri Buishand

    E-Print Network [OSTI]

    Stoffelen, Ad

    the derivation of a 10- year radar-based precipitation climatology for the Netherlands. Using rain gauges of the radar-based accumulations with an independent gauge network confirms the quality of the data set. Finally, the radar data are used to obtain exceedance probabilities and maximum rainfall depths. II. RADAR

  9. ELEVATION-DEPENDENT TRENDS IN PRECIPITATION OBSERVED BY THE NAME RADAR NETWORK

    E-Print Network [OSTI]

    Rutledge, Steven

    i THESIS ELEVATION-DEPENDENT TRENDS IN PRECIPITATION OBSERVED BY THE NAME RADAR NETWORK Submitted BY ANGELA K. ROWE ENTITLED ELEVATION- DEPENDENT TRENDS IN PRECIPITATION OBSERVED BY THE NAME RADAR NETWORK BY THE NAME RADAR NETWORK Radar data from the 2004 North American Monsoon Experiment (NAME) Enhanced Observing

  10. Considerations for the use of radar-derived precipitation estimates in determining return intervals for extreme

    E-Print Network [OSTI]

    Allen, Robert J.

    to those based on traditional rain gauge networks. For both the radar and gauge data, increasing, considerable differences between radar ARF and gauge ARF exist. Radar ARF decays at a faster rate (with increasing area) than gauge ARF. For a basin size of 20,000 km2 , the percent difference between radar ARF

  11. Sesso Temtica: Analise de dados PolSAR usando Teoria da Informao (PolSAR Data Analysis Using Information Theory) Coordenadores: Dr. Abrao D. C. Nascimento (UFPE) e Dr. Alejandro C. Frery (UFAL)

    E-Print Network [OSTI]

    imagens com alta resolução espacial. Entretanto, as imagens PolSAR são afetadas por um padrão de modelos que incorporam tanto a parametrização do efeito do speckle multidimensional sobre imagens Pol Informação a identificar e entender atributos em imagens PolSAR tem se mostrado uma frente de pesquisa

  12. Multipinhole collimator with 20 apertures for a brain SPECT application

    SciTech Connect (OSTI)

    Lee, Tzu-Cheng; Ellin, Justin R.; Shrestha, Uttam; Seo, Youngho, E-mail: youngho.seo@ucsf.edu [Physics Research Laboratory, Department of Radiology and Biomedical Imaging, University of California, San Francisco, California 94107 (United States); Huang, Qiu [School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030 (China); Gullberg, Grant T. [Department of Radiotracer Development and Imaging Technology, Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94702 (United States)

    2014-11-01T23:59:59.000Z

    Purpose: Several new technologies for single photon emission computed tomography (SPECT) instrumentation with parallel-hole collimation have been proposed to improve detector sensitivity and signal collection efficiency. Benefits from improved signal efficiency include shorter acquisition times and lower dose requirements. In this paper, the authors show a possibility of over an order of magnitude enhancement in photon detection efficiency (from 7.6 × 10{sup ?5} to 1.6 × 10{sup ?3}) for dopamine transporter (DaT) imaging of the striatum over the conventional SPECT parallel-hole collimators by use of custom-designed 20 multipinhole (20-MPH) collimators with apertures of 0.75 cm diameter. Methods: Quantifying specific binding ratio (SBR) of {sup 123}I-ioflupane or {sup 123}I-iometopane’s signal at the striatal region is a common brain imaging method to confirm the diagnosis of the Parkinson’s disease. The authors performed imaging of a striatal phantom filled with aqueous solution of I-123 and compared camera recovery ratios of SBR acquired between low-energy high-resolution (LEHR) parallel-hole collimators and 20-MPH collimators. Results: With only two-thirds of total acquisition time (20 min against 30 min), a comparable camera recovery ratio of SBR was achieved using 20-MPH collimators in comparison to that from the LEHR collimator study. Conclusions: Their systematic analyses showed that the 20-MPH collimator could be a promising alternative for the DaT SPECT imaging for brain over the traditional LEHR collimator, which could give both shorter scan time and improved diagnostic accuracy.

  13. Permanent scatterer InSAR reveals seasonal and long-term aquifer-system response to groundwater pumping and artificial

    E-Print Network [OSTI]

    Amelung, Falk

    with an artificial recharge program, long-term, residual, inelastic aquifer-system compaction (subsidenceSAR reveals seasonal and long-term aquifer-system response to groundwater pumping and artificial rechargePermanent scatterer InSAR reveals seasonal and long-term aquifer-system response to groundwater

  14. ERS SAR characterization of coastal polynyas in the Arctic and comparison with SSM/I and numerical model investigations

    E-Print Network [OSTI]

    Winsor, Peter

    ), and a numerical polynya model (NPM) forced by National Center for Environmental Predictions (NCEP) wind fields increases to .83. The NPM computes offshore coastal polynya widths, heat exchange, and ice production is that SAR images processed through the SAR polynya algorithm in combination with the NPM is a powerful tool

  15. Radar echo, Doppler Effect and Radar detection in the uniformly accelerated reference frame

    E-Print Network [OSTI]

    Bernhard Rothenstein; Stefan Popescu

    2006-09-14T23:59:59.000Z

    The uniformly accelerated reference frame described by Hamilton, Desloge and Philpott involves the observers who perform the hyperbolic motion with constant proper acceleration gi. They start to move from different distances measured from the origin O of the inertial reference frame K(XOY), along its OX axis with zero initial velocity. Equipped with clocks and light sources they are engaged with each other in Radar echo, Doppler Effect and Radar detection experiments. They are also engaged in the same experiments with an inertial observer at rest in K(XOY) and located at its origin O. We derive formulas that account for the experiments mentioned above. We study also the landing conditions of the accelerating observers on a uniformly moving platform.

  16. Development and characterization analysis of a radar polarimeter

    E-Print Network [OSTI]

    Bong, Soei Siang

    1984-01-01T23:59:59.000Z

    . OPERATIONAL ANALYSIS OF THE RPS Assembling the RPS. Theoretical Calculations. Losses in the RF Heads. 1. The L-Band Radar Head (1. 6 GHz). 2. The C-Band Radar Head (4. 75 GHz) 3. The X-Band Radar Head (10. 003 GHz) RF Head Stability as Measured... of the Components in the IF Section. List of Components in the L-Band RF Head. List of Components in the C-Band RF Head. List of Components in the X-Band RF Head. Detail List of Components in the L-Band RF Head . Specifications of the Components in the L...

  17. Development and characterization analysis of a radar polarimeter 

    E-Print Network [OSTI]

    Bong, Soei Siang

    1984-01-01T23:59:59.000Z

    . OPERATIONAL ANALYSIS OF THE RPS Assembling the RPS. Theoretical Calculations. Losses in the RF Heads. 1. The L-Band Radar Head (1. 6 GHz). 2. The C-Band Radar Head (4. 75 GHz) 3. The X-Band Radar Head (10. 003 GHz) RF Head Stability as Measured... of the Components in the IF Section. List of Components in the L-Band RF Head. List of Components in the C-Band RF Head. List of Components in the X-Band RF Head. Detail List of Components in the L-Band RF Head . Specifications of the Components in the L...

  18. Monitoring internal organ motion with continuous wave radar in CT

    SciTech Connect (OSTI)

    Pfanner, Florian [Institute of Medical Physics, University of Erlangen–Nürnberg, 91052 Erlangen, Germany and Siemens AG, Healthcare Sector, Siemensstr. 1, 91301 Forchheim (Germany)] [Institute of Medical Physics, University of Erlangen–Nürnberg, 91052 Erlangen, Germany and Siemens AG, Healthcare Sector, Siemensstr. 1, 91301 Forchheim (Germany); Maier, Joscha [Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)] [Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Allmendinger, Thomas; Flohr, Thomas [Siemens AG, Healthcare Sector, Siemensstr. 1, 91301 Forchheim (Germany)] [Siemens AG, Healthcare Sector, Siemensstr. 1, 91301 Forchheim (Germany); Kachelrieß, Marc [Institute of Medical Physics, University of Erlangen–Nürnberg, 91052 Erlangen, Germany and Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)] [Institute of Medical Physics, University of Erlangen–Nürnberg, 91052 Erlangen, Germany and Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)

    2013-09-15T23:59:59.000Z

    Purpose: To avoid motion artifacts in medical imaging or to minimize the exposure of healthy tissues in radiation therapy, medical devices are often synchronized with the patient's respiratory motion. Today's respiratory motion monitors require additional effort to prepare the patients, e.g., mounting a motion belt or placing an optical reflector on the patient's breast. Furthermore, they are not able to measure internal organ motion without implanting markers. An interesting alternative to assess the patient's organ motion is continuous wave radar. The aim of this work is to design, implement, and evaluate such a radar system focusing on application in CT.Methods: The authors designed a radar system operating in the 860 MHz band to monitor the patient motion. In the intended application of the radar system, the antennas are located close to the patient's body inside the table of a CT system. One receive and four transmitting antennas are used to avoid the requirement of exact patient positioning. The radar waves propagate into the patient's body and are reflected at tissue boundaries, for example at the borderline between muscle and adipose tissue, or at the boundaries of organs. At present, the authors focus on the detection of respiratory motion. The radar system consists of the hardware mentioned above as well as of dedicated signal processing software to extract the desired information from the radar signal. The system was evaluated using simulations and measurements. To simulate the radar system, a simulation model based on radar and wave field equations was designed and 4D respiratory-gated CT data sets were used as input. The simulated radar signals and the measured data were processed in the same way. The radar system hardware and the signal processing algorithms were tested with data from ten volunteers. As a reference, the respiratory motion signal was recorded using a breast belt simultaneously with the radar measurements.Results: Concerning the measurements of the test persons, there is a very good correlation (?= 0.917) between the respiratory motion phases received by the radar system and the external motion monitor. Our concept of using an array of transmitting antennas turned out to be widely insensitive to the positioning of the test persons. A time shift between the respiratory motion curves recorded with the radar system and the motion curves from the external respiratory monitor was observed which indicates a slight difference between internal organ motion and motion detected by the external respiratory monitor. The simulations were in good accordance with the measurements.Conclusions: A continuous wave radar operating in the near field of the antennas can be used to determine the respiratory motion of humans accurately. In contrast to trigger systems used today, the radar system is able to measure motion inside the body. If such a monitor was routinely available in clinical CT, it would be possible optimizing the scan start with respect to the respiratory state of the patient. Breathing commands would potentially widely be avoided, and as far as uncooperative patients or children are concerned, less sedation might be necessary. Further applications of the radar system could be in radiation therapy or interventional imaging for instance.

  19. Wide band stepped frequency ground penetrating radar

    DOE Patents [OSTI]

    Bashforth, M.B.; Gardner, D.; Patrick, D.; Lewallen, T.A.; Nammath, S.R.; Painter, K.D.; Vadnais, K.G.

    1996-03-12T23:59:59.000Z

    A wide band ground penetrating radar system is described embodying a method wherein a series of radio frequency signals is produced by a single radio frequency source and provided to a transmit antenna for transmission to a target and reflection therefrom to a receive antenna. A phase modulator modulates those portions of the radio frequency signals to be transmitted and the reflected modulated signal is combined in a mixer with the original radio frequency signal to produce a resultant signal which is demodulated to produce a series of direct current voltage signals, the envelope of which forms a cosine wave shaped plot which is processed by a Fast Fourier Transform Unit 44 into frequency domain data wherein the position of a preponderant frequency is indicative of distance to the target and magnitude is indicative of the signature of the target. 6 figs.

  20. Wide band stepped frequency ground penetrating radar

    DOE Patents [OSTI]

    Bashforth, Michael B. (Buellton, CA); Gardner, Duane (Santa Maria, CA); Patrick, Douglas (Santa Maria, CA); Lewallen, Tricia A. (Ventura, CA); Nammath, Sharyn R. (Santa Barbara, CA); Painter, Kelly D. (Goleta, CA); Vadnais, Kenneth G. (Alexandria, VA)

    1996-01-01T23:59:59.000Z

    A wide band ground penetrating radar system (10) embodying a method wherein a series of radio frequency signals (60) is produced by a single radio frequency source (16) and provided to a transmit antenna (26) for transmission to a target (54) and reflection therefrom to a receive antenna (28). A phase modulator (18) modulates those portion of the radio frequency signals (62) to be transmitted and the reflected modulated signal (62) is combined in a mixer (34) with the original radio frequency signal (60) to produce a resultant signal (53) which is demodulated to produce a series of direct current voltage signals (66) the envelope of which forms a cosine wave shaped plot (68) which is processed by a Fast Fourier Transform unit 44 into frequency domain data (70) wherein the position of a preponderant frequency is indicative of distance to the target (54) and magnitude is indicative of the signature of the target (54).

  1. A comparison of the SAR and Vaneslow equations on three Texas soils

    E-Print Network [OSTI]

    Guth, David Leonard

    1984-01-01T23:59:59.000Z

    A COMPARISON OF THE SAR AND VANESLOW EQUATIONS ON THREE TEXAS SOILS A Thesis by DAVID LEONARD GUTH Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May... 1984 Major Subject: Soil Science A COMPARISON OF THE SAR AND VANESLOW EQUATIONS ON THREE TEXAS SOILS A Thesis by DAVID LEONARD GOTH Approved as to- tyle and content by: Kir W, Brown (Chairman of Committee) ic ar H. Loeppert (Member) Wt bert...

  2. LCLS X-ray mirror measurements using a large aperture visible light interferometer

    SciTech Connect (OSTI)

    McCarville, T; Soufli, R; Pivovaroff, M

    2011-03-02T23:59:59.000Z

    Synchrotron or FEL X-ray mirrors are required to deliver an X-ray beam from its source to an experiment location, without contributing significantly to wave front distortion. Accurate mirror figure measurements are required prior to installation to meet this intent. This paper describes how a 300 mm aperture phasing interferometer was calibrated to <1 nm absolute accuracy and used to mount and measure 450 mm long flats for the Linear Coherent Light Source (LCLS) at Stanford Linear Accelerator Center. Measuring focus mirrors with an interferometer requires additional calibration, because high fringe density introduces systematic errors from the interferometer's imaging optics. This paper describes how these errors can be measured and corrected. The calibration approaches described here apply equally well to interferometers larger than 300 mm aperture, which are becoming more common in optics laboratories. The objective of this effort was to install LCLS flats with < 10 nm of spherical curvature, and < 2 nm rms a-sphere. The objective was met by measuring the mirrors after fabrication, coating and mounting, using a 300 mm aperture phasing interferometer calibrated to an accuracy < 1 nm. The key to calibrating the interferometer accurately was to sample the error using independent geometries that are available. The results of those measurements helped identify and reduce calibration error sources. The approach used to measure flats applies equally well to focus mirrors, provided an additional calibration is performed to measure the error introduced by fringe density. This calibration has been performed on the 300 mm aperture interferometer, and the measurement correction was evaluated for a typical focus mirror. The 300 mm aperture limitation requires stitching figure measurements together for many X-ray mirrors of interest, introducing another possible error source. Stitching is eliminated by applying the calibrations described above to larger aperture instruments. The authors are presently extending this work to a 600 mm instrument. Instruments with 900 mm aperture are now becoming available, which would accommodate the largest mirrors of interest.

  3. Direct aperture optimization for online adaptive radiation therapy

    SciTech Connect (OSTI)

    Mestrovic, Ante; Milette, Marie-Pierre; Nichol, Alan; Clark, Brenda G.; Otto, Karl [Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada and Medical Physics, BC Cancer Agency-Vancouver Centre, Vancouver, British Columbia (Canada); Physics and Astronomy, University of British Columbia, Vancouver, British Columbia (Canada) and Medical Physics, BC Cancer Agency-Centre for the Southern Interior, Kelowna, British Columbia (Canada); Department of Radiation Oncology, BC Cancer Agency-Vancouver Centre, Vancouver, British Columbia (Canada); Medical Physics, Ottawa Hospital Regional Cancer Centre, Ottawa, Ontario (Canada); Medical Physics, BC Cancer Agency-Vancouver Centre, Vancouver, British Columbia (Canada)

    2007-05-15T23:59:59.000Z

    This paper is the first investigation of using direct aperture optimization (DAO) for online adaptive radiation therapy (ART). A geometrical model representing the anatomy of a typical prostate case was created. To simulate interfractional deformations, four different anatomical deformations were created by systematically deforming the original anatomy by various amounts (0.25, 0.50, 0.75, and 1.00 cm). We describe a series of techniques where the original treatment plan was adapted in order to correct for the deterioration of dose distribution quality caused by the anatomical deformations. We found that the average time needed to adapt the original plan to arrive at a clinically acceptable plan is roughly half of the time needed for a complete plan regeneration, for all four anatomical deformations. Furthermore, through modification of the DAO algorithm the optimization search space was reduced and the plan adaptation was significantly accelerated. For the first anatomical deformation (0.25 cm), the plan adaptation was six times more efficient than the complete plan regeneration. For the 0.50 and 0.75 cm deformations, the optimization efficiency was increased by a factor of roughly 3 compared to the complete plan regeneration. However, for the anatomical deformation of 1.00 cm, the reduction of the optimization search space during plan adaptation did not result in any efficiency improvement over the original (nonmodified) plan adaptation. The anatomical deformation of 1.00 cm demonstrates the limit of this approach. We propose an innovative approach to online ART in which the plan adaptation and radiation delivery are merged together and performed concurrently--adaptive radiation delivery (ARD). A fundamental advantage of ARD is the fact that radiation delivery can start almost immediately after image acquisition and evaluation. Most of the original plan adaptation is done during the radiation delivery, so the time spent adapting the original plan does not increase the overall time the patient has to spend on the treatment couch. As a consequence, the effective time allotted for plan adaptation is drastically reduced. For the 0.25, 0.5, and 0.75 cm anatomical deformations, the treatment time was increased by only 2, 4, and 6 s, respectively, as compared to no plan adaptation. For the anatomical deformation of 1.0 cm the time increase was substantially larger. The anatomical deformation of 1.0 cm represents an extreme case, which is rarely observed for the prostate, and again demonstrates the limit of this approach. ARD shows great potential for an online adaptive method with minimal extension of treatment time.

  4. ORIGINAL PAPER Synergistic use of very high-frequency radar

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    carbon sequestration (Hyde et al. 2007; Lucas et al. 2000; Skole and Tucker 1993). The traditional field · Introduction Accurate estimation of aboveground bio- mass is essential to better understand the carbon cycleSAR . Scanning lidar. Profiling lidar. Aboveground biomass . Best subsets regression . Carbon 1 Introduction

  5. Coherent radar ice thickness measurements over the Greenland ice sheet

    E-Print Network [OSTI]

    Gogineni, S. Prasad; Tammana, Dilip; Braaten, David A.; Leuschen, C.; Legarsky, J.; Kanagaratnam, P.; Stiles, J.; Allen, C.; Jezek, K.; Akins, T.

    2001-12-27T23:59:59.000Z

    We developed two 150-MHz coherent radar depth sounders for ice thickness measurements over the Greenland ice sheet. We developed one of these using connectorized components and the other using radio frequency integrated circuits (RFICs). Both...

  6. Sea surface wave reconstruction from marine radar images

    E-Print Network [OSTI]

    Qi, Yusheng, S.M. Massachusetts Institute of Technology

    2012-01-01T23:59:59.000Z

    The X-band marine radar is one type of remote sensing technology which is being increasingly used to measure sea surface waves nowadays. In this thesis, how to reconstruct sea surface wave elevation maps from X-band marine ...

  7. Earth curvature and atmospheric refraction effects on radar signal propagation.

    SciTech Connect (OSTI)

    Doerry, Armin Walter

    2013-01-01T23:59:59.000Z

    The earth isn't flat, and radar beams don't travel straight. This becomes more noticeable as range increases, particularly at shallow depression/grazing angles. This report explores models for characterizing this behavior.

  8. Radar Vehicle Detection Within Four Quadrant Gate Crossings

    E-Print Network [OSTI]

    Illinois at Urbana-Champaign, University of

    of the exit gate · Less delay between entry and exit gate descent · Extends the exit gate delay only) Methodology 4) Results 5) Conclusions 6) Acknowledgments Exit Gate Operating Modes (EGOM) Radar Vehicle

  9. A spatial display for Ground-Penetrating Radar change detection

    E-Print Network [OSTI]

    Quimby, Paul W

    2013-01-01T23:59:59.000Z

    Ground-Penetrating Radar (GPR) enables the exploration and mapping of subterranean volumes for applications such as construction, humanitarian demining, archeology, and environmental science. In each of these applications, ...

  10. Sandia National Laboratories: evaluating wind-turbine/radar impacts

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

    Air Space (NAS) radar system, which has led to a blanket rejection of several wind-farm developments. To improve the siting and ... Last Updated: December 3, 2014 Go To...

  11. An airborne digital processor for radar scatterometer data

    E-Print Network [OSTI]

    Yeadon, David Steven

    1977-01-01T23:59:59.000Z

    AN AIRBORNE DIGITAL PROCESSOR FOR RADAR SCATTEROMETER DATA A Thesis by DAVID STEVEN YEADON Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August 1977... Major Subject: Electrical Engineering AN AIRBORNE DIGITAL PROCESSOR FOR RADAR SCATTEROMETER DATA A Thesis by DAVID STEVEN YEADON Approved as to style and content by: (Chairman o Committee) Head of epartment) ( (Member ) (Member) August 1977...

  12. Differences in radar derived rainfall amounts due to sampling intervals

    E-Print Network [OSTI]

    Zdenek, David James

    1986-01-01T23:59:59.000Z

    DIFFERENCES IN RADAR DERIVED RAINFALL AMOUNTS DUE TO SAMPLING INTERVALS A Thesis by DAVID JAMES ZDENEK Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE... December 1986 Major Subject: Meteorology DIFFERENCES IN RADAR DERIVED RAINFALL AMOUNTS DUE TO SAMPLING INTERVALS A Thesis by DAVID JAMES ZDENEK Approved as to style and content by: eorge L. Huebner (Chairman of Committee) CP~ CG~& Robert C...

  13. SAR Motion Products: Tools for Monitoring Changes in Sea Ice Mass Balance and Thickness Distribution

    E-Print Network [OSTI]

    Geiger, Cathleen

    decrease in a warming climate. For example, in a weakening ice pack, we could expect convergence storminess in the Arctic; (b) a seasonal ice pack of reduced thickness; and (c) large scale changes in driftSAR Motion Products: Tools for Monitoring Changes in Sea Ice Mass Balance and Thickness

  14. Information fusion for estimation of summer MIZ ice concentration from SAR imagery

    E-Print Network [OSTI]

    Haverkamp, Donna S.; Tsatsoulis, Costas

    1999-05-01T23:59:59.000Z

    In this paper we define the concept of information fusion and show how we used it to estimate summer sea ice concentration in the marginal ice zone (MIZ) from single-channel SAR satellite imagery, We used data about melt stage, wind speed...

  15. Case Study 1 Detection of Oil Slicks using MODIS and SAR

    E-Print Network [OSTI]

    Meyers, Steven D.

    ecosystems. Every year, huge quantities of oil and petroleum products enter the sea, land, and groundwaterCase Study 1 Detection of Oil Slicks using MODIS and SAR Imagery Chuanmin Hu1 , Xiaofeng Li2 , William G. Pichel3 1.1 Background Oil pollution can cause extensive damage to marine and terrestrial

  16. Tide Model Accuracy in the Amundsen Sea, Antarctica, from InSAR Observations of Ice

    E-Print Network [OSTI]

    draining this region are out of balance; satellite records have documented glacier thinning, acceleration is currently losing ice mass at a rate comparable to that of the entire Greenland Ice Sheet. · Glaciers the flow of ice is removed using a prediction derived from tracking features in SAR backscatter intensity

  17. GTD-based Scattering Models for Bistatic SAR Brian D. Rigling and Randolph L. Moses

    E-Print Network [OSTI]

    Moses, Randolph L.

    modelling of six scattering primitives: sphere, tophat, trihedral, dihedral, cylinder, and flat plate validated high-frequency simulations. Keywords: SAR, bistatic, ground map, scattering models, Geometric of diffraction (GTD) Ref. 6, the high-frequency scattering response from a complex object is well

  18. High Resolution SAR Interferometry: influence of local topography in the context of glacier monitoring

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    High Resolution SAR Interferometry: influence of local topography in the context of glacier the opportu- nity to measure temperate glacier surface topography and displacement between the two for glacier activity monitoring, by providing regular measure- ments such as surface topography, velocity

  19. Combining Optical and SAR data to monitor temperate glaciers E. Trouve1

    E-Print Network [OSTI]

    Boyer, Edmond

    Combining Optical and SAR data to monitor temperate glaciers E. Trouv´e1 , G. Vasile1 , M. Gay2 , P 129 - Fax: 33+ 145 813 794 - nicolas@tsi.enst.fr Abstract Monitoring temperate glaciers activity the compution of high reso- lution DTM, the detection of glacial lakes and the mea- surement of glacier surface

  20. Glacier flow monitoring by digital camera and space-borne SAR images

    E-Print Network [OSTI]

    Boyer, Edmond

    1 Glacier flow monitoring by digital camera and space-borne SAR images Flavien Vernier1, Renaud glaciers and to measure their surface velocity by different techniques. However, the image size) images the motion of Alpine glaciers. The optical images are acquired by a digital camera installed near

  1. Offshore wind resources from satellite SAR Charlotte Bay Hasager, Merete Bruun Christiansen, Morten Nielsen,

    E-Print Network [OSTI]

    Offshore wind resources from satellite SAR Charlotte Bay Hasager, Merete Bruun Christiansen, Morten ocean wind maps were described. For offshore wind resource estimation based on satellite observations and the near-coastal zone (up to 40 km offshore) is not mapped. In contrast, Envisat ASAR wind maps can

  2. ASSIMILATION OF DOPPLER RADAR DATA INTO NUMERICAL WEATHER MODELS

    SciTech Connect (OSTI)

    Chiswell, S.; Buckley, R.

    2009-01-15T23:59:59.000Z

    During the year 2008, the United States National Weather Service (NWS) completed an eight fold increase in sampling capability for weather radars to 250 m resolution. This increase is expected to improve warning lead times by detecting small scale features sooner with increased reliability; however, current NWS operational model domains utilize grid spacing an order of magnitude larger than the radar data resolution, and therefore the added resolution of radar data is not fully exploited. The assimilation of radar reflectivity and velocity data into high resolution numerical weather model forecasts where grid spacing is comparable to the radar data resolution was investigated under a Laboratory Directed Research and Development (LDRD) 'quick hit' grant to determine the impact of improved data resolution on model predictions with specific initial proof of concept application to daily Savannah River Site operations and emergency response. Development of software to process NWS radar reflectivity and radial velocity data was undertaken for assimilation of observations into numerical models. Data values within the radar data volume undergo automated quality control (QC) analysis routines developed in support of this project to eliminate empty/missing data points, decrease anomalous propagation values, and determine error thresholds by utilizing the calculated variances among data values. The Weather Research and Forecasting model (WRF) three dimensional variational data assimilation package (WRF-3DVAR) was used to incorporate the QC'ed radar data into input and boundary conditions. The lack of observational data in the vicinity of SRS available to NWS operational models signifies an important data void where radar observations can provide significant input. These observations greatly enhance the knowledge of storm structures and the environmental conditions which influence their development. As the increase in computational power and availability has made higher resolution real-time model simulations possible, the need to obtain observations to both initialize numerical models and verify their output has become increasingly important. The assimilation of high resolution radar observations therefore provides a vital component in the development and utility of numerical model forecasts for both weather forecasting and contaminant transport, including future opportunities to improve wet deposition computations explicitly.

  3. Operating the LCLS Gas Attenuator and Gas Detector System with Apertures of 6mm Diameter

    SciTech Connect (OSTI)

    Ryutov, D.D.; Bionta, R.M.; Hau-Riege, S.P.; Kishiyama, K.I.; Roeben, M.D.; Shen, S.; /LLNL, Livermore; Stefan, P.M.; /SLAC; ,

    2010-11-17T23:59:59.000Z

    The possibility of increasing the apertures of the LCLS gas attenuator/gas detector system is considered. It is shown that increase of the apertures from 3 to 6 mm, together with 4-fold reduction of the operation pressure does not adversely affect the vacuum conditions upstream or downstream. No change of the pump speed and the lengths of the differential pumping cells is required. One minor modification is the use of 1.5 cm long tubular apertures in the end cells of the differential pumping system. Reduction of the pressure does not affect performance of the gas attenuator/gas detector system at the FEL energies below, roughly, 2 keV. Some minor performance degradation occurs at higher energies.

  4. Off-momentum dynamic aperture for lattices in the RHIC heavy ion runs

    SciTech Connect (OSTI)

    Luo Y.; Bai, M.; Blaskiewicz, M.; Gu, X.; Fischer, W.; Marusic, A.; Roser, T.; Tepikian, S.; Zhang, S.

    2012-05-20T23:59:59.000Z

    To reduce transverse emittance growth rates from intrabeam scattering in the RHIC heavy ion runs, a lattice with an increased phase advance in the arc FODO cells was adopted in 2008-2011. During these runs, a large beam loss due to limited off-momentum dynamic aperture was observed during longitudinal RF re-bucketing and with transverse cooling. Based on the beam loss observations in the previous ion runs and the calculated off-momentum apertures, we decided to adopt the lattice used before 2008 for the 2012 U-U and Cu-Au runs. The observed beam decay and the measured momentum aperture in the 2012 U-U run are presented.

  5. Graphene based tunable fractal Hilbert curve array broadband radar absorbing screen for radar cross section reduction

    SciTech Connect (OSTI)

    Huang, Xianjun, E-mail: xianjun.huang@manchester.ac.uk [School of Electrical and Electronic Engineering, University of Manchester, Manchester M13 9PL (United Kingdom); College of Electronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China); Hu, Zhirun [School of Electrical and Electronic Engineering, University of Manchester, Manchester M13 9PL (United Kingdom); Liu, Peiguo [College of Electronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

    2014-11-15T23:59:59.000Z

    This paper proposes a new type of graphene based tunable radar absorbing screen. The absorbing screen consists of Hilbert curve metal strip array and chemical vapour deposition (CVD) graphene sheet. The graphene based screen is not only tunable when the chemical potential of the graphene changes, but also has broadband effective absorption. The absorption bandwidth is from 8.9GHz to 18.1GHz, ie., relative bandwidth of more than 68%, at chemical potential of 0eV, which is significantly wider than that if the graphene sheet had not been employed. As the chemical potential varies from 0 to 0.4eV, the central frequency of the screen can be tuned from 13.5GHz to 19.0GHz. In the proposed structure, Hilbert curve metal strip array was designed to provide multiple narrow band resonances, whereas the graphene sheet directly underneath the metal strip array provides tunability and averagely required surface resistance so to significantly extend the screen operation bandwidth by providing broadband impedance matching and absorption. In addition, the thickness of the screen has been optimized to achieve nearly the minimum thickness limitation for a nonmagnetic absorber. The working principle of this absorbing screen is studied in details, and performance under various incident angles is presented. This work extends applications of graphene into tunable microwave radar cross section (RCS) reduction applications.

  6. Using Satellite Radar Data to Map and Monitor Variations in Great Lakes Ice Cover

    E-Print Network [OSTI]

    , for image-to-image classification, a library of backscatter signatures of different ice types is needed) classification technique has shown that different ice types in the ice cover can be identified and mapped for use with calibrated SAR imagery. III. SAR ICE CLASSIFICATION AND MAPPING During the 1997 winter season

  7. Incoherent scatter radar detection of enhanced plasma line in ionospheric E-region over Arecibo

    E-Print Network [OSTI]

    Pradipta, Rezy

    2006-01-01T23:59:59.000Z

    A series of incoherent scatter radar (ISR) observation were conducted at the Arecibo Observatory from December 27, 2005 until January 3, 2006. From plasma line measurements that were taken during this radar campaign, we ...

  8. Accuracy and resolution of shuttle radar topography mission data Bridget Smith and David Sandwell

    E-Print Network [OSTI]

    Sandwell, David T.

    Accuracy and resolution of shuttle radar topography mission data Bridget Smith and David Sandwell: General or miscellaneous. Citation: Smith, B., and D. Sandwell, Accuracy and resolution of shuttle radar

  9. Near real-time runoff estimation using spatially distributed radar rainfall data

    E-Print Network [OSTI]

    Hadley, Jennifer Lyn

    2004-09-30T23:59:59.000Z

    associated with rainfall. Radar networks, such as the Next Generation Weather Radar (NEXRAD) of the National Weather Service (NWS), which are widely available and continue to improve in quality and resolution, can accomplish these tasks. In general, a...

  10. Near Real-Time Runoff Estimation Using Spatially Distributed Radar Rainfall Data

    E-Print Network [OSTI]

    Hadley, Jennifer Lynn

    associated with rainfall. Radar networks, such as the Next Generation Weather Radar (NEXRAD) of the National Weather Service (NWS), which are widely available and continue to improve in quality and resolution, can accomplish these tasks. In general, a...

  11. Analog FIR Filter Used for Range-Optimal Pulsed Radar Applications

    E-Print Network [OSTI]

    Su, Eric Chen

    2014-08-13T23:59:59.000Z

    Matched filter is one of the most critical block in radar applications. With different measured range and relative velocity of a target we will need different bandwidth of the matched filter to maximize the radar signal to noise ratio (SNR...

  12. On reconciling ground-based with spaceborne normalized radar cross section measurements

    E-Print Network [OSTI]

    Baumgartner, F.; Munk, J.; Jezek, K. C.; Gogineni, Sivaprasad

    2002-02-01T23:59:59.000Z

    This study examines differences in the normalized radar cross section, derived from ground-based versus spaceborne radar data. A simple homogeneous half-space model, indicates that agreement between the two improves as 1) ...

  13. SMALL MOLECULE INHIBITORS OF THE SARS-COV NSP15 ENDORIBONUCLEASE, MECHANISM OF ACTION AND INSIGHT INTO CORONAVIRUS INFECTION 

    E-Print Network [OSTI]

    Ortiz Alcantara, Joanna M.

    2010-07-14T23:59:59.000Z

    The Severe Acute Respiratory Syndrome (SARS) virus encodes several unusual RNA processing enzymes, including Nsp15, an endoribonuclease that preferentially cleaves 3? of uridylates through a Ribonuclease A-like mechanism. ...

  14. Draft genome sequence of strain HIMB100, a cultured representative of the SAR116 clade of marine Alphaproteobacteria

    E-Print Network [OSTI]

    Grote, Jana

    2011-01-01T23:59:59.000Z

    Strain HIMB100 is a planktonic marine bacterium in the class Alphaproteobacteria. This strain is of interest because it is one of the first known isolates from a globally ubiquitous clade of marine bacteria known as SAR116 ...

  15. A PodBased DualBeam SAR Gordon Farquharson, William N. Junek, Arun Ramanathan, Stephen Frasier,

    E-Print Network [OSTI]

    Tessier, Russell

    300 MHz center frequency selected upconversion. solid­state power over land water surfaces. Imagery were collected squinted beams, though interferometric data were collected. Notable look­angle dependences observed surface NRCS under very low wind conditions. Keywords SAR

  16. Phase retrieval with the transport-of-intensity equation in an arbitrarily-shaped aperture by iterative discrete cosine transforms

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

    Huang, Lei; Zuo, Chao; Idir, Mourad; Qu, Weijuan; Asundi, Anand

    2015-01-01T23:59:59.000Z

    A novel transport-of-intensity equation (TIE) based phase retrieval method is proposed with putting an arbitrarily-shaped aperture into the optical wavefield. In this arbitrarily-shaped aperture, the TIE can be solved under non-uniform illuminations and even non-homogeneous boundary conditions by iterative discrete cosine transforms with a phase compensation mechanism. Simulation with arbitrary phase, arbitrary aperture shape, and non-uniform intensity distribution verifies the effective compensation and high accuracy of the proposed method. Experiment is also carried out to check the feasibility of the proposed method in real measurement. Comparing to the existing methods, the proposed method is applicable for any types of phasemore »distribution under non-uniform illumination and non-homogeneous boundary conditions within an arbitrarily-shaped aperture, which enables the technique of TIE with hard aperture become a more flexible phase retrieval tool in practical measurements.« less

  17. Master's thesis: "Wind speed measurements in an offshore wind farm by remote sensing: Comparison of radar satellite TerraSAR-X and ground-based

    E-Print Network [OSTI]

    Peinke, Joachim

    Master's thesis: "Wind speed measurements in an offshore wind farm by remote sensing: Comparison of the Offshore wind farm alpha ventus with 12 wind turbines, substation and met mast Fino1. Southerly winds cause (wake) caused by wind farms and especially for the interaction of large offshore wind farms, which can

  18. Surface Plasmon Resonance Imaging Using a High Numerical Aperture Microscope Objective

    E-Print Network [OSTI]

    Zare, Richard N.

    Surface Plasmon Resonance Imaging Using a High Numerical Aperture Microscope Objective Bo Huang-5080 We designed, constructed, and tested a surface plasmon resonance (SPR) microscope using a high, combined with various methods to shorten the surface plasmon propaga- tion length, achieves diffraction

  19. Change Detection Using Synthetic Aperture Sonar: Preliminary Results from the Larvik Trial

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    detection technology for autonomous underwater vehicles (AUVs) equipped with synthetic aperture sonars (SAS of route survey with unmanned systems, this means repeatedly surveying ports and important transit routes the processing have been proposed, however the field as applied to the underwater environment remains in its

  20. Aperture Test for Internal Target Operation in the JLAB High-current ERL

    SciTech Connect (OSTI)

    Zhang, Shukui

    2013-06-01T23:59:59.000Z

    A high current beam transmission test has been successfully completed at the JLAB FEL Facility, culminating in very low-loss transmission of a high current CW beam through a small aperture. The purpose of this test was to determine if an ERL is capable of meeting the stringent requirements imposed by the use of a 1018/cm3 internal gas target proposed for the DarkLight experiment*. Minimal beamline modifications were made to create a machine configuration that is substantially different from those used in routine UV or IR FEL operation. A sustained (8 hour) high power beam run was performed, with clean transmission through a 2 mm transverse aperture of 127 mm length simulating the target configuration. A beam size of 50 um (rms) was measured near the center of the aperture. Experimental data from a week-long test run consistently exhibited beam loss of only a few ppm on the aperture while running 4.5 mA current at 100 MeV -- or nearly 0.5 MW beam power. This surpassed the users? expectation and demonstrated a unique capability of an ERL for this type of experiments. This report presents a summary of the experiment, a brief overview of our activities, and outlines future plans.

  1. Modified composite Fresnel zone plates with high numerical apertures Qing Cao and Jurgen Jahns

    E-Print Network [OSTI]

    Jahns, Jürgen

    Modified composite Fresnel zone plates with high numerical apertures Qing Cao and J¨urgen Jahns Traditional Fresnel zone plates (TFZPs) can be used for the focusing and imaging of soft x-rays and EUV proposed the modified Fresnel zone plates that can produce sharp Gaussian focal spots (we call them

  2. High Resolution Backside Imaging and Thermography using a Numerical Aperture Increasing Lens

    E-Print Network [OSTI]

    High Resolution Backside Imaging and Thermography using a Numerical Aperture Increasing Lens Shawn inspection alone, it is necessary to develop techniques, such as thermography, with the capability ­solid immersion lens microscopy and thermography. Standard non-contact optical resolution is limited

  3. Compact description of substrate-related aberrations in high numerical-aperture optical

    E-Print Network [OSTI]

    Stallinga, Sjoerd

    ) and advanced optical disk4 (AOD) make use of GaN lasers with wavelength 0.405 m, with BD using a numericalCompact description of substrate-related aberrations in high numerical-aperture optical disk) through the substrate. Deviations of the thickness from the nominal value result in spherical aberration

  4. FMCW radars for snow research Hans-Peter Marshall a,b,, Gary Koh a

    E-Print Network [OSTI]

    Marshall, Hans-Peter

    -available impulse radars are currently used operationally in Scandinavia's deep snow packs (e.g. Sand and Bruland

  5. Vertical Structure of Tropical Cyclone Rainbands as seen by the TRMM Precipitation Radar

    E-Print Network [OSTI]

    Houze Jr., Robert A.

    1 Vertical Structure of Tropical Cyclone Rainbands as seen by the TRMM Precipitation Radar Deanna A's Precipitation Radar (TRMM PR) show the vertical structure of tropical cyclone rainbands. Radar-echo statistics show that rainbands have a two-layered structure, with distinct modes separated by the melting layer

  6. Off-The-Grid X-band Weather Radar Network for the West

    E-Print Network [OSTI]

    Gilbes, Fernando

    and target. CayeyNWS radar Mayaguez The Problem #12;Puerto Rico Test Bed · Multi-level Research Team · Low · Relay Stations #12;Network Node · Weather Radar · Processing Computer · Wireless Link #12;X-Band Weather cost · Better Merging algorithms · More Radars.... #12;PR Test Bed Team #12;Questions · ??? #12;Live

  7. Radar Network Scanning Coordination Based on Ensemble Transform Kalman Filtering Variance

    E-Print Network [OSTI]

    White, Luther

    Radar Network Scanning Coordination Based on Ensemble Transform Kalman Filtering Variance an ensemble Kalman filter is used as a criterion with which to op- timize radar network scanning strategies, is a function of the retrieval scanning parameters. It is shown that the mapping from radar parameters

  8. SCANNING CLOUD RADAR OBSERVATIONS AT AZORES: PRELIMINARY 3D CLOUD PRODUCTS

    E-Print Network [OSTI]

    SCANNING CLOUD RADAR OBSERVATIONS AT AZORES: PRELIMINARY 3D CLOUD PRODUCTS P. Kollias, I. Jo, A, NY www.bnl.gov ABSTRACT The deployment of the Scanning W-Band ARM Cloud Radar (SWACR) during the AMF campaign at Azores signals the first deployment of an ARM Facility-owned scanning cloud radar and offers

  9. ERAD 2008 -THE FIFTH EUROPEAN CONFERENCE ON RADAR IN METEOROLOGYAND HYDROLOGY 1. Introduction

    E-Print Network [OSTI]

    Haak, Hein

    , and the enhancement of the radar processing with capabilities found in modern radar equipment. In the European tender receivers and all data processing equipment in the radar sensor was replaced with modern equipment. The short pulse mode (0.8 microseconds) is used for PRFs up to 1200 Hz. To enhance reliability the thyratron

  10. A New Coherent Radar for Ice Sounding in Greenland A. Moussessian

    E-Print Network [OSTI]

    Kansas, University of

    A New Coherent Radar for Ice Sounding in Greenland A. Moussessian 1 , R.L. Jordan 1 , E. Rodriguez of this radar on board a P-3 aircraft took place in May of 1999 over Greenland with successful results blanking. The first deployment of this radar took place in May of 1999 in Greenland. During this deployment

  11. 2 1 APPLICATION GALLERY 1.1 Tracking ``Fuzzy'' Storms in Doppler Radar Images

    E-Print Network [OSTI]

    Barron, John

    and tornadoes. The Doppler radar generates intensity and radial velocity images, examples of which are shown Doppler radar radial and velocity image (a) (b) (c) (d) Figure 1.2: The storm tracks for the (a) 5 th , (b2 1 APPLICATION GALLERY 1.1 Tracking ``Fuzzy'' Storms in Doppler Radar Images J. L. Barron 1 , R. E

  12. Determining weather radar antenna pointing using signals detected from the sun at low antenna elevations

    E-Print Network [OSTI]

    Stoffelen, Ad

    Determining weather radar antenna pointing using signals detected from the sun at low antenna radiation of the sun for checking of the antenna alignment and of the sensitivity of the receiver chain is a well established method in weather radar maintenance, and radar manufacturers offer sun calibration

  13. Resultados obtidos com a utilizao de imagens de RADAR do satlite ALOS

    E-Print Network [OSTI]

    Resultados obtidos com a utilização de imagens de RADAR do satélite ALOS no combate ao desmatamento Documentos Indicativos de desmatamento com ALOS PALSAR #12;#12;INDICAR- Indicador de desmatamento por imagens de RADAR · Projeto desenvolvido pelo CSR/IBAMA · Utiliza imagens de RADAR do satélite Japonês ALOS

  14. Cloud radar Doppler spectra in drizzling stratiform clouds: 2. Observations and microphysical modeling of drizzle evolution

    E-Print Network [OSTI]

    Cloud radar Doppler spectra in drizzling stratiform clouds: 2. Observations and microphysical I, the influence of cloud microphysics and dynamics on the shape of cloud radar Doppler spectra in warm stratiform clouds was discussed. The traditional analysis of radar Doppler moments was extended

  15. Influence of small scale rainfall variability on standard comparison tools between radar and rain gauge data

    E-Print Network [OSTI]

    in revised form 18 October 2013 Accepted 8 November 2013 Rain gauges and weather radars do not measure some usual practice. © 2013 Elsevier B.V. All rights reserved. Keywords: Radar­rain gauge comparison are tipping bucket rain gauges, disdrometers, weather radars and (passive or active) sensors onboard

  16. A radar study of the interaction between lightning and precipitation

    SciTech Connect (OSTI)

    Holden, D.N.; Ulbrich, C.W.

    1988-01-01T23:59:59.000Z

    A radar study was made of the interaction between lightning and precipitation with the 430 MHz Doppler radar at the Arecibo Observatory in Puerto Rico. On one occasion, the spectral power at Doppler velocities near that corresponding to the updraft increased substantially within a fraction of a second after a discharge was detected in the beam. Calculations were made to simulate the effect of an electric field change on mean Doppler velocity for a distribution of droplets in a thunderstorm. 13 refs., 4 figs.

  17. Elements of a continuous-wave borehole radar. Final report

    SciTech Connect (OSTI)

    Caffey, T.W.H. [Sandia National Labs., Albuquerque, NM (United States). Geophysical Technology Dept.

    1997-08-01T23:59:59.000Z

    The theory is developed for the antenna array for a proposed continuous-wave, ground-penetrating radar for use in a borehole, and field measurements are presented. Accomplishments include the underground measurement of the transmitting beam in the azimuth plane, active azimuth-steering of the transmitting beam, and the development of a range-to-target algorithm. The excellent performance of the antenna array supports the concept of a continuous-wave borehole radar. A field-prototype should be developed for use in both geothermal zones and for the exploration and recovery of oil and gas.

  18. LDRD final report : first application of geospatial semantic graphs to SAR image data.

    SciTech Connect (OSTI)

    Brost, Randolph C.; McLendon, William Clarence,

    2013-01-01T23:59:59.000Z

    Modeling geospatial information with semantic graphs enables search for sites of interest based on relationships between features, without requiring strong a priori models of feature shape or other intrinsic properties. Geospatial semantic graphs can be constructed from raw sensor data with suitable preprocessing to obtain a discretized representation. This report describes initial work toward extending geospatial semantic graphs to include temporal information, and initial results applying semantic graph techniques to SAR image data. We describe an efficient graph structure that includes geospatial and temporal information, which is designed to support simultaneous spatial and temporal search queries. We also report a preliminary implementation of feature recognition, semantic graph modeling, and graph search based on input SAR data. The report concludes with lessons learned and suggestions for future improvements.

  19. Transpolarising Trihedral Corner Reflector Characterisation Using a GB-SAR System

    E-Print Network [OSTI]

    Ferrer, Pere J; Aguasca, Albert; Pipia, Luca; Gonzalez-Arbesu, Jose M; Fabregas, Xavier; Romeu, Jordi

    2011-01-01T23:59:59.000Z

    The use of a low profile, light weight and easy to fabricate transpolarising surface placed on one side of a trihedral corner reflector (TCR) as polarimetric calibrator is presented in this letter. The transpolarising-TCR (TTCR) presents a high backscattered cross-polar response contrary to standard TCRs. The performance of this device has been tested at X-band using the UPC GB-SAR.

  20. Transpolarising Trihedral Corner Reflector Characterisation Using a GB-SAR System

    E-Print Network [OSTI]

    Pere J. Ferrer; Carlos Lopez-Martinez; Albert Aguasca; Luca Pipia; Jose M. Gonzalez-Arbesu; Xavier Fabregas; Jordi Romeu

    2011-02-10T23:59:59.000Z

    The use of a low profile, light weight and easy to fabricate transpolarising surface placed on one side of a trihedral corner reflector (TCR) as polarimetric calibrator is presented in this letter. The transpolarising-TCR (TTCR) presents a high backscattered cross-polar response contrary to standard TCRs. The performance of this device has been tested at X-band using the UPC GB-SAR.

  1. Development of a folded compact range and its application in performing coherent change detection and interferometric ISAR measurement

    SciTech Connect (OSTI)

    Sorensen, K.W.; Zittel, D.H. [Sandia National Labs., Albuquerque, NM (United States); Littlejohn, J.H. [Geo-Centers, Inc., Albuquerque, NM (United States)

    1996-09-01T23:59:59.000Z

    A folded compact range configuration has been developed at the Sandia National Laboratories` compact range antenna and radar cross section measurement facility as a means of performing indoor, environmentally controlled far-field simulations of synthetic aperture radar (SAR) measurements of distributed target samples (i.e. gravel, sand, etc.). In particular, the folded compact range configuration has been used to perform both highly sensitive coherent change detection (CCD) measurements and interferometric inverse synthetic aperture radar (IFSAR) measurements, which, in addition to the two-dimensional spatial resolution afforded by typical interferometric SAR (ISAR) processing, provides resolution of the relative height of targets with accuracies on the order of a wavelength. This paper describes the development of the folded compact range, as well as the coherent change detection and interferometric measurements that have been made with the system. The measurement have been very successful, and have demonstrated not only the viability of the folded compact range concept in simulating SAR CCD and IFSAR measurements, but also its usefulness as a tool in the research and development of SAR CCD and IFSAR image generation and measurement methodologies.

  2. Measurements of ionospheric effects on wideband signals at VHF

    SciTech Connect (OSTI)

    Fitzgerald, T.J.

    1998-08-17T23:59:59.000Z

    Radars operating at very high frequency (VHF) have enhanced foliage and ground penetration compared to radars operated at higher frequencies. For example, VHF systems operated from airplanes have been used as synthetic aperture radars (SAR); a satellite-borne VHF SAR would have considerable utility. In order to operate with high resolution it would have to use both a large relative bandwidth and a large aperture. A satellite-borne radar would likely have to operate at altitudes above the maximum density of the ionosphere; the presence of the ionosphere in the propagation path of the radar will cause a deterioration of the performance because of dispersion over the bandwidth. The author presents measurements of the effects of the ionosphere on radar signals propagated from a source on the surface of the Earth and received by instruments on the FORTE satellite at altitudes of 800 km. The author employs signals with a 90 MHz bandwidth centered at 240 MHz with a continuous digital recording period of 0.6 s.

  3. Folded Compact Range Development and Coherent Change Detection Measurement Project

    SciTech Connect (OSTI)

    Sorensen, K.W.

    1995-03-01T23:59:59.000Z

    A novel, folded compact range configuration has been developed at the Sandia National Laboratories compact range antenna and radar cross section measurement facility, operated by the Radar/Antenna Department 2343, as a means of performing indoor, environmentally-controlled, far-field simulations of synthetic aperture radar (SAR) coherent change detection (CCD) measurements. This report describes the development of the folded compact range configuration, as well as the initial set of coherent change detection measurements made with the system. These measurements have been highly successful, and have demonstrated the viability of the folded compact range concept in simulating SAR CCD measurements. It is felt that follow-on measurements have the potential of contributing significantly to the body of knowledge available to the scientific community involved in CCD image generation and processing, and that this tool will be a significant aid in the research and development of change detection methodologies.

  4. First observations of tracking clouds using scanning ARM cloud radars

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

    Borque, Paloma; Giangrande, Scott; Kollias, Pavlos

    2014-12-01T23:59:59.000Z

    Tracking clouds using scanning cloud radars can help to document the temporal evolution of cloud properties well before large drop formation (‘‘first echo’’). These measurements complement cloud and precipitation tracking using geostationary satellites and weather radars. Here, two-dimensional (2-D) Along-Wind Range Height Indicator (AW-RHI) observations of a population of shallow cumuli (with and without precipitation) from the 35-GHz scanning ARM cloud radar (SACR) at the DOE Atmospheric Radiation Measurements (ARM) program Southern Great Plains (SGP) site are presented. Observations from the ARM SGP network of scanning precipitation radars are used to provide the larger scale context of the cloud fieldmore »and to highlight the advantages of the SACR to detect the numerous, small, non-precipitating cloud elements. A new Cloud Identification and Tracking Algorithm (CITA) is developed to track cloud elements. In CITA, a cloud element is identified as a region having a contiguous set of pixels exceeding a preset reflectivity and size threshold. The high temporal resolution of the SACR 2-D observations (30 sec) allows for an area superposition criteria algorithm to match cloud elements at consecutive times. Following CITA, the temporal evolution of cloud element properties (number, size, and maximum reflectivity) is presented. The vast majority of the designated elements during this cumulus event were short-lived non-precipitating clouds having an apparent life cycle shorter than 15 minutes. The advantages and disadvantages of cloud tracking using an SACR are discussed.« less

  5. Assessment Of The Wind Farm Impact On The Radar

    E-Print Network [OSTI]

    Norman, Evgeny D

    2010-01-01T23:59:59.000Z

    This study shows the means to evaluate the wind farm impact on the radar. It proposes the set of tools, which can be used to realise this objective. The big part of report covers the study of complex pattern propagation factor as the critical issue of the Advanced Propagation Model (APM). Finally, the reader can find here the implementation of this algorithm - the real scenario in Inverness airport (the United Kingdom), where the ATC radar STAR 2000, developed by Thales Air Systems, operates in the presence of several wind farms. Basically, the project is based on terms of the department "Strategy Technology & Innovation", where it has been done. Also you can find here how the radar industry can act with the problem engendered by wind farms. The current strategies in this area are presented, such as a wind turbine production, improvements of air traffic handling procedures and the collaboration between developers of radars and wind turbines. The possible strategy for Thales as a main pioneer was given as ...

  6. Generating nonlinear FM chirp radar signals by multiple integrations

    DOE Patents [OSTI]

    Doerry, Armin W. (Albuquerque, NM)

    2011-02-01T23:59:59.000Z

    A phase component of a nonlinear frequency modulated (NLFM) chirp radar pulse can be produced by performing digital integration operations over a time interval defined by the pulse width. Each digital integration operation includes applying to a respectively corresponding input parameter value a respectively corresponding number of instances of digital integration.

  7. PAVEMENT OVERLAY THICKNESS EVALUATION USING GROUND PENTRATING RADAR (GPR)

    E-Print Network [OSTI]

    Shan, Jie

    PAVEMENT OVERLAY THICKNESS EVALUATION USING GROUND PENTRATING RADAR (GPR) Dwayne Harris, M.Sc., PG University, West Lafayette, IN 47907 jshan@ecn.purdue.edu ABSTRACT Accurate knowledge of pavement thickness is important information to have both at a network and project level. This information aids in pavement

  8. Automatic Radar Antenna Scan Type Recognition in Electronic

    E-Print Network [OSTI]

    Barshan, Billur

    Automatic Radar Antenna Scan Type Recognition in Electronic Warfare BILLUR BARSHAN BAHAEDDIN ERAVCI in electronic warfare (EW). The stages of the algorithm are scan period estimation, preprocessing (normalization Continuous-wave EW Electronic warfare EM Electromagnetic LFM Linear frequency modulation DTW Dynamic time

  9. RADAR OBSERVATIONS OF COMET 103P/HARTLEY 2

    SciTech Connect (OSTI)

    Harmon, John K.; Nolan, Michael C.; Howell, Ellen S.; Taylor, Patrick A. [Arecibo Observatory, National Astronomy and Ionosphere Center, HC3 Box 53995, Arecibo, Puerto Rico 00612 (Puerto Rico); Giorgini, Jon D., E-mail: harmon@naic.edu [Jet Propulsion Laboratory, California Institute of Technology, MS 301-150, 4800 Oak Grove Dr., Pasadena, California 91109 (United States)

    2011-06-10T23:59:59.000Z

    Comets rarely come close enough to be studied intensively with Earth-based radar. The most recent such occurrence was when Comet 103P/Hartley 2 passed within 0.12 AU in late 2010 October, less than two weeks before the EPOXI flyby. This offered a unique opportunity to improve pre-encounter trajectory knowledge and obtain complementary physical data for a spacecraft-targeted comet. 103P/Hartley 2 is only the fourth comet nucleus to be imaged with radar and already the second to be identified as an elongated, bilobate object based on its delay-Doppler signature. The images show the dominant spin mode to be a rotation about the short axis with a period of 18.2 hr. The nucleus has a low radar albedo consistent with a surface density of 0.5-1.0 g cm{sup -3}. A separate echo component was detected from large (>cm) grains ejected anisotropically with velocities of several to tens of meters per second. Radar shows that, in terms of large-grain production, 103P/Hartley 2 is an unusually active comet for its size.

  10. First observations of tracking clouds using scanning ARM cloud radars

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

    Borque, Paloma [McGill Univ., Montreal, QC (Canada); Giangrande, Scott [Brookhaven National Lab. (BNL), Upton, NY (United States); Kollias, Pavlos [McGill Univ., Montreal, QC (Canada)

    2014-12-01T23:59:59.000Z

    Tracking clouds using scanning cloud radars can help to document the temporal evolution of cloud properties well before large drop formation (‘‘first echo’’). These measurements complement cloud and precipitation tracking using geostationary satellites and weather radars. Here, two-dimensional (2-D) Along-Wind Range Height Indicator (AW-RHI) observations of a population of shallow cumuli (with and without precipitation) from the 35-GHz scanning ARM cloud radar (SACR) at the DOE Atmospheric Radiation Measurements (ARM) program Southern Great Plains (SGP) site are presented. Observations from the ARM SGP network of scanning precipitation radars are used to provide the larger scale context of the cloud field and to highlight the advantages of the SACR to detect the numerous, small, non-precipitating cloud elements. A new Cloud Identification and Tracking Algorithm (CITA) is developed to track cloud elements. In CITA, a cloud element is identified as a region having a contiguous set of pixels exceeding a preset reflectivity and size threshold. The high temporal resolution of the SACR 2-D observations (30 sec) allows for an area superposition criteria algorithm to match cloud elements at consecutive times. Following CITA, the temporal evolution of cloud element properties (number, size, and maximum reflectivity) is presented. The vast majority of the designated elements during this cumulus event were short-lived non-precipitating clouds having an apparent life cycle shorter than 15 minutes. The advantages and disadvantages of cloud tracking using an SACR are discussed.

  11. Automated Target Recognition Using Passive Radar and Coordinated Flight Models

    E-Print Network [OSTI]

    Lanterman, Aaron

    of altitude and range. The Numerical Electromagnetic Code (NEC2) computes the antenna gain pattern, so Georgia Institute of Technology, Atlanta, GA 30332, USA ABSTRACT Rather than emitting pulses, passive system is in the transmitter, whereas designers of "hitchhiking" or "parasitic" radars have high

  12. The use of composite radar photographs in synoptic weather analysis

    E-Print Network [OSTI]

    Smith, G. D.

    1957-01-01T23:59:59.000Z

    of ursa. Velooity of line, figure K3 Xn addition t* th? foregoing infornacion, the bases and tope of leyscs end tops of convective echoes oan be ruporced. With certain radar installations, end under certain conditions, tha height of thu freeaing...

  13. Lower Limits on Aperture Size for an ExoEarth-Detecting Coronagraphic Mission

    E-Print Network [OSTI]

    Stark, Christopher C; Mandell, Avi; Clampin, Mark; Domagal-Goldman, Shawn D; McElwain, Michael W; Stapelfeldt, Karl R

    2015-01-01T23:59:59.000Z

    The yield of Earth-like planets will likely be a primary science metric for future space-based missions that will drive telescope aperture size. Maximizing the exoEarth candidate yield is therefore critical to minimizing the required aperture. Here we describe a method for exoEarth candidate yield maximization that simultaneously optimizes, for the first time, the targets chosen for observation, the number of visits to each target, the delay time between visits, and the exposure time of every observation. This code calculates both the detection time and multi-wavelength spectral characterization time required for planets. We also refine the astrophysical assumptions used as inputs to these calculations, relying on published estimates of planetary occurrence rates as well as theoretical and observational constraints on terrestrial planet sizes and classical habitable zones. Given these astrophysical assumptions, optimistic telescope and instrument assumptions, and our new completeness code that produces the hi...

  14. RF/optical shared aperture for high availability wideband communication RF/FSO links

    DOE Patents [OSTI]

    Ruggiero, Anthony J; Pao, Hsueh-yuan; Sargis, Paul

    2014-04-29T23:59:59.000Z

    An RF/Optical shared aperture is capable of transmitting and receiving optical signals and RF signals simultaneously. This technology enables compact wide bandwidth communications systems with 100% availability in clear air turbulence, rain and fog. The functions of an optical telescope and an RF reflector antenna are combined into a single compact package by installing an RF feed at either of the focal points of a modified Gregorian telescope.

  15. Coded aperture imaging with self-supporting uniformly redundant arrays. [Patent application

    DOE Patents [OSTI]

    Fenimore, E.E.

    1980-09-26T23:59:59.000Z

    A self-supporting uniformly redundant array pattern for coded aperture imaging. The invention utilizes holes which are an integer times smaller in each direction than holes in conventional URA patterns. A balance correlation function is generated where holes are represented by 1's, nonholes are represented by -1's, and supporting area is represented by 0's. The self-supporting array can be used for low energy applications where substrates would greatly reduce throughput.

  16. Cryogenics for a 5 Tesla Superconducting Solenoid with Large Aperture at DESY

    SciTech Connect (OSTI)

    Gadwinkel, E.; Lierl, H.; Notz, D.; Schaffran, J.; Schoeneburg, B. [Deutsches Elektronen-Synchrotron, DESY, Hamburg, 22607 (Germany); Herzog, H. [Deutsches Elektronen-Synchrotron, DESY, Hamburg, 22607 (Germany); Linde Kryotechnik A.G., plant operation section at DESY, Pfungen, 8422 (Switzerland)

    2004-06-23T23:59:59.000Z

    A large aperture superconducting solenoid-magnet with fields up to 5.25 Tesla is being set up as high field test facility at DESY. It is used to measure prototype time projection chambers foreseen as detectors for a future high energy physics collider experiment. The new cryogenic supply of this magnet within the existing HERA cryogenic helium system is described. The cryogenic control, operation and results are outlined.

  17. Method for generating small and ultra small apertures, slits, nozzles and orifices

    DOE Patents [OSTI]

    Khounsary, Ali M. (Hinsdale, IL)

    2012-05-22T23:59:59.000Z

    A method and device for one or more small apertures, slits, nozzles and orifices, preferably having a high aspect ratio. In one embodiment, one or more alternating layers of sacrificial layers and blocking layers are deposited onto a substrate. Each sacrificial layer is made of a material which preferably allows a radiation to substantially pass through. Each blocking layer is made of a material which substantially blocks the radiation.

  18. Measured Radiation and Background Levels During Transmission of Megawatt Electron Beams Through Millimeter Apertures

    E-Print Network [OSTI]

    Alarcon, R; Benson, S V; Bertozzi, W; Boyce, J R; Cowan, R; Douglas, D; Evtushenko, P; Fisher, P; Ihloff, E; Kalantarians, N; Kelleher, A; Kossler, W J; Legg, R; Long, E; Milner, R G; Neil, G R; Ou, L; Schmookler, B; Tennant, C; Tschalaer, C; Williams, G P; Zhang, S

    2013-01-01T23:59:59.000Z

    We report measurements of photon and neutron radiation levels observed while transmitting a 0.43 MW electron beam through millimeter-sized apertures and during beam-off, but accelerating gradient RF-on, operation. These measurements were conducted at the Free-Electron Laser (FEL) facility of the Jefferson National Accelerator Laboratory (JLab) using a 100 MeV electron beam from an energy-recovery linear accelerator. The beam was directed successively through 6 mm, 4 mm, and 2 mm diameter apertures of length 127 mm in aluminum at a maximum current of 4.3 mA (430 kW beam power). This study was conducted to characterize radiation levels for experiments that need to operate in this environment, such as the proposed DarkLight Experiment. We find that sustained transmission of a 430 kW continuous-wave (CW) beam through a 2 mm aperture is feasible with manageable beam-related backgrounds. We also find that during beam-off, RF-on operation, multipactoring inside the niobium cavities of the accelerator cryomodules is ...

  19. Measured Radiation and Background Levels During Transmission of Megawatt Electron Beams Through Millimeter Apertures

    SciTech Connect (OSTI)

    Alarcon, Ricardo [Arizona State University, Glendale, AZ (United States); Balascuta, S. [Arizona State University, Glendale, AZ (United States); Benson, Stephen V. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Bertozzi, William [Massachusetts Institute of Technology, Cambridge, MA (United States); Boyce, James R. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Cowan, Ray [Massachusetts Institute of Technology, Cambridge, MA (United States); Douglas, David R. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Evtushenko, Pavel [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Fisher, P. [Massachusetts Institute of Technology, Cambridge, MA (United States); Ihloff, Ernest E. [Hampton University, Hampton, VA (United States); Kalantarians, Narbe [Hampton University, Hampton, VA (United States); Kelleher, Aidan Michael [Massachusetts Institute of Technology, Cambridge, MA (United States); Krossler, W. J. [William and Mary College, Williamsburg, VA (United States); Legg, Robert A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Long, Elena [University of New Hampshire, Durham, NH (United States); Milner, Richard [Massachusetts Institute of Technology, Cambridge, MA (United States); Neil, George R. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Ou, Longwu [Massachusetts Institute of Technology, Cambridge, MA (United States); Schmookler, Barack Abraham [Massachusetts Institute of Technology, Cambridge, MA (United States); Tennant, Christopher D. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Tschalar, C. [Massachusetts Institute of Technology, Cambridge, MA (United States); Williams, Gwyn P. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Zhang, Shukui [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

    2013-11-01T23:59:59.000Z

    We report measurements of photon and neutron radiation levels observed while transmitting a 0.43 MW electron beam through millimeter-sized apertures and during beam-off, but accelerating gradient RF-on, operation. These measurements were conducted at the Free-Electron Laser (FEL) facility of the Jefferson National Accelerator Laboratory (JLab) using a 100 MeV electron beam from an energy-recovery linear accelerator. The beam was directed successively through 6 mm, 4 mm, and 2 mm diameter apertures of length 127 mm in aluminum at a maximum current of 4.3 mA (430 kW beam power). This study was conducted to characterize radiation levels for experiments that need to operate in this environment, such as the proposed DarkLight Experiment. We find that sustained transmission of a 430 kW continuous-wave (CW) beam through a 2 mm aperture is feasible with manageable beam-related backgrounds. We also find that during beam-off, RF-on operation, multipactoring inside the niobium cavities of the accelerator cryomodules is the primary source of ambient radiation when the machine is tuned for 130 MeV operation.

  20. Design of a near-field coded aperture cameras for high-resolution medical and industrial gamma-ray imaging

    E-Print Network [OSTI]

    Accorsi, Roberto, 1971-

    2001-01-01T23:59:59.000Z

    Coded Aperture Imaging is a technique originally developed for X-ray astronomy, where typical imaging problems are characterized by far-field geometry and an object made of point sources distributed over a mainly dark ...

  1. Measurement of fracture aperture fields using transmitted light: An evaluation of measurement errors and their influence on

    E-Print Network [OSTI]

    Detwiler, Russell

    Scott E. Pringle and Robert J. Glass Flow Visualization and Processes Laboratory, Sandia National Laboratories, Albuquerque, New Mexico Abstract. Understanding of single-phase and multiphase flow and transport light transmission techniques yield quantitative measurements of aperture, solute concentration

  2. Space-based detection of wetlands' surface water level changes from L-band SAR interferometry

    E-Print Network [OSTI]

    Amelung, Falk

    , 2006; Dai et al., 2002; Kimura & Yamaguchi, 2000), mining and large-scale geotechnical projects (e., 1998). The above applications measure the displacement of solid surfaces, whether they are rocks, soil and the vertical vegetation allow a double-bounce reflection of the transmitted radar signal back to the satellite

  3. A CLOSE COMPANION SEARCH AROUND L DWARFS USING APERTURE MASKING INTERFEROMETRY AND PALOMAR LASER GUIDE STAR ADAPTIVE OPTICS

    SciTech Connect (OSTI)

    Bernat, David [Department of Astronomy, Cornell University, Ithaca, NY 14853 (United States); Bouchez, Antonin H.; Cromer, John L.; Dekany, Richard G.; Moore, Anna M. [California Institute of Technology, Pasadena, CA 91125 (United States); Ireland, Michael; Tuthill, Peter [Sydney Institute for Astrophysics, School of Physics, University of Sydney (Australia); Martinache, Frantz [National Astronomical Observatory of Japan, Subaru Telescope, Hilo, HI 96720 (United States); Angione, John; Burruss, Rick S.; Guiwits, Stephen R.; Henning, John R.; Hickey, Jeff; Kibblewhite, Edward; McKenna, Daniel L.; Petrie, Harold L.; Roberts, Jennifer; Shelton, J. Chris; Thicksten, Robert P.; Trinh, Thang [Palomar Laser Guide Star Adaptive Optics Team, Palomar Observatory, California Institute of Technology, Palomar Mountain, CA 92060 (United States)

    2010-06-01T23:59:59.000Z

    We present a close companion search around 16 known early L dwarfs using aperture masking interferometry with Palomar laser guide star adaptive optics (LGS AO). The use of aperture masking allows the detection of close binaries, corresponding to projected physical separations of 0.6-10.0 AU for the targets of our survey. This survey achieved median contrast limits of {Delta}K {approx} 2.3 for separations between 1.2 {lambda}/D-4{lambda}/D and {Delta}K {approx} 1.4 at 2/3 {lambda}/D. We present four candidate binaries detected with moderate-to-high confidence (90%-98%). Two have projected physical separations less than 1.5 AU. This may indicate that tight-separation binaries contribute more significantly to the binary fraction than currently assumed, consistent with spectroscopic and photometric overluminosity studies. Ten targets of this survey have previously been observed with the Hubble Space Telescope as part of companion searches. We use the increased resolution of aperture masking to search for close or dim companions that would be obscured by full aperture imaging, finding two candidate binaries. This survey is the first application of aperture masking with LGS AO at Palomar. Several new techniques for the analysis of aperture masking data in the low signal-to-noise regime are explored.

  4. RADARSAT ScanSAR Wind Retrieval Under Hurricane Conditions Congling Nie and David G. Long Department of Electrical and Computer Engineering,

    E-Print Network [OSTI]

    Long, David G.

    RADARSAT ScanSAR Wind Retrieval Under Hurricane Conditions Congling Nie and David G. Long-422-4884 Email:nie@mers.byu.edu ABSTRACT RADARSAT-1 ScanSAR SWA images of Hurricane Katrina are used to retrieve/s, suggesting that the high resolution wind retrieval algorithm can work under hurricane conditions. Except

  5. Thioulouse, J., J. Devillers, D. Chessel, and Y. Auda. 1991. Graphical techniques for multidimensional data analysis. Pages 153-205 in J. Devillers and W. Karcher, editors. Applied Multivariate Analysis in SAR and Environmental Studies. Kluwer Academic

    E-Print Network [OSTI]

    Thioulouse, Jean

    Analysis in SAR and Environmental Studies. Kluwer Academic Publishers. http://pbil.univ-lyon1.fr/R/articles Analysis in SAR and Environmental Studies. Kluwer Academic Publishers. http://pbil.univ-lyon1.fr/R/articles Analysis in SAR and Environmental Studies. Kluwer Academic Publishers. http://pbil.univ-lyon1.fr/R/articles

  6. Diversity and depth-specific distribution of SAR11 cluster rRNA genes from marine planktonic bacteria

    SciTech Connect (OSTI)

    Field, K.G.; Gordon, D.; Wright, T. [Oregon State Univ., Corvallis, OR (United States)] [and others

    1997-01-01T23:59:59.000Z

    Small-subunit (SSU) ribosomal DNA (rDNA) gene clusters are phylogenetically related sets of SSU rRNA genes, commonly encountered in genes amplified from natural populations. Genetic variability in gene clusters could result form artifacts (polymerase error or PCR chimera formation), microevolution (variation among rrn copies within strains), or macroevolution (genetic divergence correlated with long-term evolutionary divergence). To better understand gene clusters, this study assessed genetic diversity and distribution of a single environmental SSU rDNA gene cluster, the SAR11 cluster. SAR11 cluster genes, from an uncultured group of the {alpha} subclass of the class Proteobacteria, have been recovered from coastal and midoceanic waters of the North Atlantic and Pacific. We cloned and bidirectionally sequenced 23 new SAR11 cluster 16S rRNA genes, from 80 and 250 m im the Sargasso Sea and from surface coastal waters of the Atlantic and Pacific, and analyzed them with previously published sequences. Two SAR11 genes were obviously PCR chimeras, but the biological (nonchimeric) origins of most subgroups within the cluster were confirmed by independent recovery from separate gene libraries. Using group-specific oligonucleotide probes, we analyzed depth profiles of nucleic acids, targeting both amplified rDNAs and bulk RNAs. Two subgroups within the SAR11 cluster showed different highly depth-specific distributions. We conclude that some of the genetic diversity within the SAR11 gene cluster represents macroevolutionary divergence correlated with niche specialization. Furthermore, we demonstrate the utility for marine microbial ecology of oligonucleotide probes based on gene sequences amplified from natural populations and show that a detailed knowledge of sequence variability may be needed to effectively design these probes. 48 refs., 7 figs., 3 tabs.

  7. InSAR At Medicine Lake Area (Poland, Et Al., 2006) | Open Energy

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdfGetecGtel JumpCounty,Jump to: navigation,Information InSAR At Medicine Lake

  8. InSAR At North Brawley Geothermal Area (Eneva, Et Al., 2013) | Open Energy

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdfGetecGtel JumpCounty,Jump to: navigation,Information InSAR At Medicine

  9. InSAR At Redfield Campus Area (Oppliger, Et Al., 2008) | Open Energy

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdfGetecGtel JumpCounty,Jump to: navigation,Information InSAR At

  10. InSAR At Salton Sea Area (Eneva And Adams, 2010) | Open Energy Information

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdfGetecGtel JumpCounty,Jump to: navigation,Information InSAR AtEneva And

  11. InSAR At Walker-Lane Transitional Zone Region (Laney, 2005) | Open Energy

    Open Energy Info (EERE)

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdfGetecGtel JumpCounty,Jump to: navigation,Information InSAR AtEneva

  12. Feasibility of a borehole VHF radar technique for fracture mapping

    SciTech Connect (OSTI)

    Chang, H.T.

    1984-01-01T23:59:59.000Z

    Experiments were conducted to establish the feasibility of a downhole high-frequency electromagnetic technique for location of fractures in the vicinity of boreholes. An existing flame-cut slot in granite was filled with salt water to simulate a brine-filled fracture. A transmitter consisting of a phased dual-dipole array arranged to provide a directional signal toward the fracture was installed in a borehole opposite the fracture. A receiver operated at 30 to 300 MHz was also located in the same borehole. The radar returns from the simulated fracture were detectable in boreholes located at distances of up to 12 meters from the fracture. These results indicate for the first time the feasibility of a downhole VHF radar for use in a single borehole for detection of fractures located away from the borehole.

  13. Radar antenna pointing for optimized signal to noise ratio.

    SciTech Connect (OSTI)

    Doerry, Armin Walter; Marquette, Brandeis [General Atomics Aeronautical Systems, Inc., San Diego, CA

    2013-01-01T23:59:59.000Z

    The Signal-to-Noise Ratio (SNR) of a radar echo signal will vary across a range swath, due to spherical wavefront spreading, atmospheric attenuation, and antenna beam illumination. The antenna beam illumination will depend on antenna pointing. Calculations of geometry are complicated by the curved earth, and atmospheric refraction. This report investigates optimizing antenna pointing to maximize the minimum SNR across the range swath.

  14. Aperture lamp

    DOE Patents [OSTI]

    MacLennan, Donald A. (Gaithersburg, MD); Turner, Brian P. (Damascus, MD)

    2003-01-01T23:59:59.000Z

    A discharge lamp includes means for containing a light emitting fill, the fill being capable of absorbing light at one wavelength and re-emitting the light at a different wavelength, the light emitted from the fill having a first spectral power distribution in the absence of reflection of light back into the fill; means for exciting the fill to cause the fill to emit light; and means for reflecting some of the light emitted by the fill back into the fill while allowing some light to exit, the exiting light having a second spectral power distribution with proportionately more light in the visible region as compared to the first spectral power distribution, wherein the light re-emitted by the fill is shifted in wavelength with respect to the absorbed light and the magnitude of the shift is in relation to an effective optical path length. Another discharge lamp includes an envelope; a fill which emits light when excited disposed in the envelope; a source of excitation power coupled to the fill to excite the fill and cause the fill to emit light; and a reflective ceramic structure disposed around the envelope and defining an light emitting opening, wherein the structure comprises a sintered body built up directly on the envelope and made from a combination of alumina and silica.

  15. Digital meteorological radar data compared with digital infrared data from a geostationary meteorological satellite

    E-Print Network [OSTI]

    Henderson, Rodney Stuart

    1979-01-01T23:59:59.000Z

    OF CONTENTS Page ABSTRACT. ACKNOWLEDGMENTS. DEDICATION . iv vi TABLE OF CONTENTS . vii LIST OF TABLES. IX LIST OF FIGURES . LIST OF ACRONYMS CHAPTER xii I. INTRODUCTION 1. The Need for This Investigation 2. Present Status of Research Relating... to This Investigation 3. Objectives of the Investigation 4. Techniques and Scope of the Investigation. II. METEOROLOGICAL RADAR DATA . 10 1. Basic Radar Theory . 2. Earth Curvature Correction . 3. The TAMU Weather Radar System. 4. Data Reduction and Display 10...

  16. Improving ISR Radar Utilization (How I quit blaming the user and made the radar easier to use).

    SciTech Connect (OSTI)

    Doerry, Armin W.

    2014-08-01T23:59:59.000Z

    In modern multi - sensor multi - mode Intelligence, Surveillance, and Reconnaissance ( ISR ) platforms, the plethora of options available to a sensor/payload operator are quite large, leading to an over - worked operator often down - selecting to favorite sensors an d modes. For example, Full Motion Video (FMV) is justifiably a favorite sensor at the expense of radar modes, even if radar modes can offer unique and advantageous information. The challenge is then to increase the utilization of the radar modes in a man ner attractive to the sensor/payload operator. We propose that this is best accomplished by combining sensor modes and displays into 'super - modes'. - 4 - Acknowledgements This report is the result of a n unfunded research and development activity . Sandia Natio nal Laboratories is a multi - program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE - AC04 - 94AL850 00.

  17. Development of Nb3Sn 11 T single aperture demonstrator dipole for LHC upgrades

    SciTech Connect (OSTI)

    Zlobin, A.V.; Apollinari, G.; Andreev, N.; Barzi, E.; Kashikhin, V.V.; Nobrega, f.; Novitski, I.; /Fermilab; Auchmann, B.; Karppinen, M.; Rossi, L.; /CERN

    2011-03-01T23:59:59.000Z

    The LHC collimation upgrade foresees additional collimators installed in dispersion suppressor regions. To obtain the necessary space for the collimators, a solution based on the substitution of LHC main dipoles for stronger dipoles is being considered. CERN and FNAL have started a joint program to demonstrate the feasibility of Nb{sub 3}Sn technology for this purpose. The goal of the first phase is the design and construction of a 2-m long single-aperture demonstrator magnet with a nominal field of 11 T at 11.85 kA with 20% margin. This paper describes the magnetic and mechanical design of the demonstrator magnet and summarizes its design parameters.

  18. Ion funnel with extended mass range and reduced conductance limit aperture

    DOE Patents [OSTI]

    Tolmachev, Aleksey V. (Richland, WA); Smith, Richard D. (Richland, WA)

    2008-04-01T23:59:59.000Z

    An improved ion funnel design is disclosed that decreases the axial RF (parasite) fields at the ion funnel exit. This is achieved by addition of one or more compensation electrodes after the conductance limit electrode. Various RF voltage profiles may be applied to the various electrodes minimizing the parasite axial potential wells. The smallest RF aperture that serves as the conductance limiting electrode is further reduced over standard designs. Overall, the ion funnel improves transmission ranges of both low m/z and high m/z ions, reducing RF activation of ions and decreasing the gas load to subsequent differential pumping stages.

  19. Workshop: Dados SAR e LIDAR para Anlise de Parmetros Biofsicos e de Estrutura Vertical de Tipologias Florestais (SAR and LIDAR Data for the Analysis of Biophysical Parameters and Vertical Structure from Forest Typologies)

    E-Print Network [OSTI]

    forests, allowing the optimized planning and operational management of forest resources. Microwave, Brazil) 10:45h Design and Implementation of Lidar & Radar Surveys for Forest Carbon Monitoring in REDD

  20. SU-E-T-10: A Dosimetric Comparison of Copper to Lead-Alloy Apertures for Electron Beam Therapy

    SciTech Connect (OSTI)

    Rusk, B; Hogstrom, K; Gibbons, J; Carver, R [Mary Bird Perkins Cancer Center, Baton Rouge, LA (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To evaluate dosimetric differences of copper compared to conventional lead-alloy apertures for electron beam therapy. Methods: Copper apertures were manufactured by .decimal, Inc. and matching lead-alloy, Cerrobend, apertures were constructed for 32 square field sizes (2×2 – 20×20 cm{sup 2}) for five applicator sizes (6×6–25×25 cm{sup 2}). Percent depth-dose and off-axis-dose profiles were measured using an electron diode in water with copper and Cerrobend apertures for a subset of aperture sizes (6×6, 10×10, 25×25 cm{sup 2}) and energies (6, 12, 20 MeV). Dose outputs were measured for all field size-aperture combinations and available energies (6–20 MeV). Measurements were taken at 100 and 110 cm SSDs. Using this data, 2D planar absolute dose distributions were constructed and compared. Passing criteria were ±2% of maximum dose or 1-mm distance-to-agreement for 99% of points. Results: A gamma analysis of the beam dosimetry showed 93 of 96 aperture size, applicator, energy, and SSD combinations passed the 2%/1mm criteria. Failures were found for small field size-large applicator combinations at 20 MeV and 100-cm SSD. Copper apertures showed a decrease in bremsstrahlung production due to copper's lower atomic number compared to Cerrobend (greatest difference was 2.5% at 20 MeV). This effect was most prominent at the highest energies with large amounts of shielding material present (small field size-large applicator). Also, an increase in electrons scattered from the collimator edge of copper compared to Cerrobend resulted in an increased dose at the field edge for copper at shallow depths (greatest increase was 1% at 20 MeV). Conclusion: Apertures for field sizes ?6×6 cm{sup 2} at any energy, or for small fields (?4×4 cm{sup 2}) at energies <20 MeV, showed dosimetric differences less than 2%/1mm for more than 99% of points. All field size-applicator size-energy combinations passed 3%/1mm criteria for 100% of points. Work partially funded by .decimal, Inc. (Sanford, FL)

  1. Applications of Remote Sensing Techniques to Identify Major Faults in the Island of Puerto Rico using SAR and SLAR images

    E-Print Network [OSTI]

    Gilbes, Fernando

    Rico using SAR and SLAR images Ashlyann Arana Morales1 , Daniel J. Mercado Rosario2 1 Bo Tanama 1B Calle 1 Arecibo P.R, 00612-5578, ashlyann.arana@upr.edu 2 #15 Calle Iglesia Quebradilla P.R, 00678

  2. Better Air Quality in Asian and Pacific Rim Cities (BAQ 2002) 16 Dec 2002 18 Dec 2002, Hong Kong SAR

    E-Print Network [OSTI]

    Columbia University

    of recyclable waste City type Organic waste Inorganic waste Recyclable waste Paper Glass Meta l Plastic Fiber waste Moisture % Density (ton/m3) Heating value (kJ/kg) Rubber % Glass % Metal % city/year Organic SAR PS-18- 1 Development of Municipal Solid Waste Incineration Technologies Li Xiaodong Yan Jianhua

  3. SMALL MOLECULE INHIBITORS OF THE SARS-COV NSP15 ENDORIBONUCLEASE, MECHANISM OF ACTION AND INSIGHT INTO CORONAVIRUS INFECTION

    E-Print Network [OSTI]

    Ortiz Alcantara, Joanna M.

    2010-07-14T23:59:59.000Z

    . Benzopurpurin B, C-473872, and Congo red are competitive inhibitors, according to kinetic studies and were demonstrated to bind SARS-CoV Nsp15 by a differential scanning fluorimetry assay. Benzopurpurin B also inhibited the Nsp15 orthologs from two other...

  4. Design of large aperture superferric quadrupole magnets for an in-flight fragment separator

    SciTech Connect (OSTI)

    Zaghloul, Aziz; Kim, Dogyun; Kim, Jangyoul; Kim, Mijung; Kim, Myeongjin; Yun, Chongcheoul; Kim, Jongwon [Rare Isotope Science Project, Institute for Basic Science, Yuseong, Daejeon, 305-811 (Korea, Republic of)

    2014-01-29T23:59:59.000Z

    Superferric quadrupole magnets to be used for in-flight fragment separator have been designed. A quadrupole magnet triplet for beam focusing is placed in a cryostat together with superconducting correction coils. To maximize acceptance of rare isotope beams produced by projectile fragmentation, it is essential to use large-aperture quadrupole magnets. The pole tip radius is 17 cm in the current design, and we tried to enlarge the aperture with 3D analysis on magnetic fields. In the front end of the separator, where a target and beam dump are located, we plan to use two sets of quadrupole triplets made of high-Tc superconductor (HTS) operating at 20-50 K considering high radiation heat load. The HTS magnet will use warm iron poles. Both low-Tc and high-Tc superconductors are acquired for test winding, and two kinds of dewar and cryostat are under construction to perform the coil and magnet tests. The magnetic design of superferric quadrupole is mainly discussed.

  5. Review and discussion of the development of synthetic aperture focusing technique for ultrasonic testing (SAFT-UT)

    SciTech Connect (OSTI)

    Busse, L J; Collins, H D; Doctor, S R

    1984-03-01T23:59:59.000Z

    The development and capabilities of synthetic aperture focusing techniques for ultrasonic testing (SAFT-UT) are presented. The purpose of SAFT-UT is to produce high-resolution images of the interior of opaque objects. The goal of this work is to develop and implement methods which can be used to detect and to quantify the extent of defects and cracks in critical components of nuclear reactors (pressure vessels, primary piping systems, and nozzles). This report places particular emphasis upon the practical experimental results that have been obtained using SAFT-UT as well as the theoretical background that underlies synthetic aperture focusing. A discussion regarding high-speed and real-time implementations of two- and three-dimensional synthetic aperture focusing is also presented.

  6. Incorporating WAAS Data Into an Ionospheric Model for Correcting Satellite Radar

    E-Print Network [OSTI]

    Toews, Carl

    at the Millstone Hill Satellite Tracking Radar. She currently holds a joint appointment with the Atmospheric corrections to radar measurements, incorporating data from a single receiver to generate TEC estimates that the GRIMS ionospheric model degenerates during times of sharp spatial TEC gradients, e.g. during geomagnetic

  7. Vertical Structure of Tropical Cyclone Rainbands as Seen by the TRMM Precipitation Radar

    E-Print Network [OSTI]

    Houze Jr., Robert A.

    Vertical Structure of Tropical Cyclone Rainbands as Seen by the TRMM Precipitation Radar DEANNA A Measurement Mission satellite's Precipitation Radar (TRMM PR) show the vertical structure of tropical cyclone separated by the melting layer. The ice layer is a combination of particles imported from the eyewall

  8. Vertical Structure of Tropical Cyclone Rainbands as seen by the TRMM Precipitation Radar

    E-Print Network [OSTI]

    Houze Jr., Robert A.

    1 Vertical Structure of Tropical Cyclone Rainbands as seen by the TRMM Precipitation Radar Deanna A (TRMM PR) show the vertical structure of tropical cyclone rainbands. Radar-echo2 statistics show that rainbands have a two-layered structure, with distinct modes separated by the3 melting layer. The ice layer

  9. Operational Monitoring of Weather Radar Receiving Chain Using the Sun IWAN HOLLEMAN

    E-Print Network [OSTI]

    Stoffelen, Ad

    Operational Monitoring of Weather Radar Receiving Chain Using the Sun IWAN HOLLEMAN Royal, is presented. The ``online'' method is entirely based on the analysis of sun signals in the polar volume data- termining the weather radar antenna pointing at low elevations using sun signals, and it is suited

  10. MECHANICAL VIBRATION SENSING FOR STRUCTURAL HEALTH MONITORING USING A MILLIMETER-WAVE DOPPLER RADAR SENSOR

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    MECHANICAL VIBRATION SENSING FOR STRUCTURAL HEALTH MONITORING USING A MILLIMETER-WAVE DOPPLER RADAR of structural health monitoring (SHM). In this paper, we report on a millimeter-wave Doppler radar sensor sensing, millimeter-waves, structural health monitoring. INTRODUCTION Structural health monitoring based

  11. Ensemble Kalman Filter Assimilation of Doppler Radar Data with a Compressible Nonhydrostatic Model: OSS Experiments

    E-Print Network [OSTI]

    Xue, Ming

    Ensemble Kalman Filter Assimilation of Doppler Radar Data with a Compressible Nonhydrostatic Model on an ensemble Kalman filter (EnKF) method and tested with simulated radar data from a supercell storm for at least 2 h. 1. Introduction Since its introduction by Evensen (1994), the en- semble Kalman filter (En

  12. Wind Profiling by Doppler Weather Radar Iwan Holleman (holleman@knmi.nl)

    E-Print Network [OSTI]

    Stoffelen, Ad

    Wind Profiling by Doppler Weather Radar Iwan Holleman (holleman@knmi.nl) Royal Netherlands wind profiles at a high temporal resolution. Several algorithms and quality ensuring procedures for the extraction of wind profiles from radar volume data have been published. A comparison and verification

  13. ERAD 2008 -THE FIFTH EUROPEAN CONFERENCE ON RADAR IN METEOROLOGY AND HYDROLOGY 1. Introduction

    E-Print Network [OSTI]

    Stoffelen, Ad

    , and the enhancement of the radar processing with capabilities found in modern radar equipment. In the European tender receivers and completely new data processing equipment. This modern equipment was integrated in the existing for PRFs up to 1200 Hz. To enhance reliability the thyratron powered switch unit, used to "fire

  14. Soil texture estimation over a semi-arid area using TERRASAR-X radar data

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Soil texture estimation over a semi-arid area using TERRASAR-X radar data M. Zribi1 , F. Kotti1 , Z Abstract In this paper, it is proposed to use TERRASAR-X data for analysis and estimation of soil surface. Simultaneously to TERRASAR-X radar acquisitions, ground measurements (texture, soil moisture and roughness) were

  15. Lagrangian Structures in Very High-Frequency Radar Data and Optimal Pollution Timing

    E-Print Network [OSTI]

    Marsden, Jerrold

    Lagrangian Structures in Very High-Frequency Radar Data and Optimal Pollution Timing Francois radar-based pollution release scheme using the hidden flow structure reduces the effect of industrial pollution in the coastal environment. INTRODUCTION The release of pollution in coastal areas [1, 2, 3] can

  16. Optimal Pollution Mitigation in Monterey Bay Based on Coastal Radar Data and Nonlinear

    E-Print Network [OSTI]

    Marsden, Jerrold

    Optimal Pollution Mitigation in Monterey Bay Based on Coastal Radar Data and Nonlinear Dynamics run-off which is a typical source of pollution in the bay. We show that a HF radar-based pollution release scheme using this flow structure reduces the impact of pollution on the coastal envi- ronment

  17. Radar Sounding of Glaciers in Greenland C. Allen, B, Wohletz, and S, Gogineni

    E-Print Network [OSTI]

    Kansas, University of

    Radar Sounding of Glaciers in Greenland C. Allen, B, Wohletz, and S, Gogineni The University on several flights over Greenland glaciers during the summer of 1995. The radar data were collected the theory and present results of the homomorphic deconvolution procedure. INTRODUCTION The Greenland

  18. 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

  19. 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

  20. High frequency radar and its application to fresh water Lorelle A. Meadows a,

    E-Print Network [OSTI]

    Ruf, Christopher

    ) at a Doppler shift corresponding very nearly to the phase velocity of the radially ad- vancing and receding frequency of the radar, c is the radial velocity of the Bragg resonant waves and cem is the speed of light average radiated powers, respectively. The effective offshore range for these radars was found to be 18 km

  1. Performance comparison of pulse-pair and wavelets methods for the pulse Doppler weather radar

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    - eters. The radar reflectivity (Z), the radial velocity (Vr) and the spectral width of velocities (W). [1). Generally, the meteorological targets move with speeds lower than 50 m/secs. The Doppler Effect wouldPerformance comparison of pulse-pair and wavelets methods for the pulse Doppler weather radar

  2. "A Functional Design and System Architecture of a Control System for a Weather Radar"

    E-Print Network [OSTI]

    Mountziaris, T. J.

    "A Functional Design and System Architecture of a Control System for a Weather Radar" Seidu Ibrahim Faculty Mentor: Eric Knapp Weather radars operate by transmitting pulses of very high microwave energy antenna scan, a three dimensional view of the surrounding atmosphere is created. Traditional weather

  3. Reflectivity retrieval in a networked radar environment: Demonstration from the CASA IP1

    E-Print Network [OSTI]

    Jayasumana, Anura P.

    using data from the first Integration Project (IP1) radar network in Oklahoma. Electromagnetic waves, the lowest coverage altitude gets higher with range due to earth curvature [1]. A networked radar environment is capable of high spatial coverage and temporal resolution. The Engineering Research Center for CASA

  4. Thunderstorm lightning and radar characteristics: insights on electrification and severe weather forecasting

    E-Print Network [OSTI]

    Steiger, Scott Michael

    2007-04-25T23:59:59.000Z

    THUNDERSTORM LIGHTNING AND RADAR CHARACTERISTICS: INSIGHTS ON ELECTRIFICATION AND SEVERE WEATHER FORECASTING A Dissertation by SCOTT MICHAEL STEIGER Submitted to the Office of Graduate Studies of Texas A&M University in partial... fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY December 2005 Major Subject: Atmospheric Sciences THUNDERSTORM LIGHTNING AND RADAR CHARACTERISTICS: INSIGHTS ON ELECTRIFICATION AND SEVERE WEATHER...

  5. Cloud radar Doppler spectra in drizzling stratiform clouds: 1. Forward modeling and remote sensing applications

    E-Print Network [OSTI]

    Cloud radar Doppler spectra in drizzling stratiform clouds: 1. Forward modeling and remote sensing broadening and drizzle growth in shallow liquid clouds remain not well understood. Detailed, cloudscale. Profiling, millimeterwavelength (cloud) radars can provide such observations. In particular, the first three

  6. Design of X-Band FMCW Short Range Radar Dong-hun Shin*

    E-Print Network [OSTI]

    Park, Seong-Ook

    Proposed radar system is bi-static radar type. It is adopted for increasing the isolation between Tx and Rx of a power divider. A portion of the swept signal is coupled to the mixer as reference signal. The final transmitted power of the system is under 0dBm. Received echo signal from the Rx antenna is injected to mixer

  7. Prospects of the WSR-88D Radar for Cloud Studies

    E-Print Network [OSTI]

    Melnikov, Valery M.; Zrni?, Dusan S.; Doviak, Richard J.; Chilson, Phillip B.; Mechem, David B.; Kogan, Yefim L.

    2011-04-01T23:59:59.000Z

    - flectivity field at 908 azimuth. APRIL 2011 M E L N I K O V E T A L . 863 compared measured solar radiation with model results. The Bird model (Bird and Hulstrom 1981) has been used to estimate the solar flux on the ground in the absence of clouds....S. Department of Commerce). REFERENCES Battan, L. J., 1973: Radar Observation of the Atmosphere. Uni- versity of Chicago, 324 pp. Bird, R. E., and R. L. Hulstrom, 1981: A simplified clear sky model for direct and diffuse insolation on horizontal surfaces. Solar...

  8. Radar investigation of the Cote Blanche salt dome

    E-Print Network [OSTI]

    Stewart, Robert Donald

    1974-01-01T23:59:59.000Z

    THE COTE BLANCHE SALT DOME. Geology of the Cote Blanche Salt-Dome Azea. . Economic History of the Cote BLanche Salt-Dome Azea, Salt. . Oil and gas. III. ELECTROMAGNETIC WAVE PROPAGATION. . . Radar Speed in Air and in Salt. . . Velocity...' zznd i'r. mzznz 1959) . The east, south, end west flanks are nearly vertical. However, the north side oi the dome is characterised by a massive overhang. A well drilled by Shell Oil Company, Caffrey No. 1, confirmed the presence of a minimum of 3300...

  9. North and northeast Greenland ice discharge from satellite radar interferometry

    SciTech Connect (OSTI)

    Rignot, E.J. [California Institute of Technology, Pasadena, CA (United States)] [California Institute of Technology, Pasadena, CA (United States); Gogineni, S.P. [Univ. of Kansas, Lawrence, KS (United States)] [Univ. of Kansas, Lawrence, KS (United States); Krabill, W.B. [NASA Goddard Space Flight Center, Wallops Island, VA (United States)] [and others] [NASA Goddard Space Flight Center, Wallops Island, VA (United States); and others

    1997-05-09T23:59:59.000Z

    Ice discharge from north and northeast Greenland calculated from satellite radar interferometry data of 14 outlet glaciers is 3.5 times that estimated from iceberg production. The satellite estimates, obtained at the grounding line of the outlet glaciers, differ from those obtained at the glacier front, because basal melting is extensive at the underside of the floating glacier sections. The results suggest that the north and northeast parts of the Greenland ice sheet may be thinning and contributing positively to sea-level rise. 24 refs., 3 figs., 1 tab.

  10. Mitigating Wind-Radar Interference | Department of Energy

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

    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: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment3311,Official FileEnergyAERMOD-PRIME, UnitsMitigating Wind-Radar

  11. THE REGIONAL AND DIURNAL VARIABILITY OF THE VERTICAL STRUCTURE OF PRECIPITATION SYSTEMS IN AFRICA, BASED ON TRMM PRECIPITATION RADAR DATA

    E-Print Network [OSTI]

    Geerts, Bart

    IN AFRICA, BASED ON TRMM PRECIPITATION RADAR DATA Bart Geerts1 and Teferi Dejene University of Wyoming 1 microwave radiances (e.g. Kummerow and Giglio 1994), and 14 GHz radar reflectivities (e.g. Ferreira et al-based techniques are much inferior to radar-based techniques, in principle at least, because the anvil of large

  12. Merged and corrected 915 MHz Radar Wind Profiler moments

    SciTech Connect (OSTI)

    Jonathan Helmus,Virendra Ghate, Frederic Tridon

    2014-06-25T23:59:59.000Z

    The radar wind profiler (RWP) present at the SGP central facility operates at 915 MHz and was reconfigured in early 2011, to collect key sets of measurements for precipitation and boundary layer studies. The RWP is configured to run in two main operating modes: a precipitation (PR) mode with frequent vertical observations and a boundary layer (BL) mode that is similar to what has been traditionally applied to RWPs. To address issues regarding saturation of the radar signal, range resolution and maximum range, the RWP PR mode is set to operate with two different pulse lengths, termed as short pulse (SP) and long pulse (LP). Please refer to the RWP handbook (Coulter, 2012) for further information. Data from the RWP PR-SP and PR-LP modes have been extensively used to study deep precipitating clouds, especially their dynamical structure as the RWP data does not suffer from signal attenuation during these conditions (Giangrande et al., 2013). Tridon et al. (2013) used the data collected during the Mid-latitude Continental Convective Cloud Experiment (MC3E) to improve the estimation of noise floor of the RWP recorded Doppler spectra.

  13. Merged and corrected 915 MHz Radar Wind Profiler moments

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

    Jonathan Helmus,Virendra Ghate, Frederic Tridon

    The radar wind profiler (RWP) present at the SGP central facility operates at 915 MHz and was reconfigured in early 2011, to collect key sets of measurements for precipitation and boundary layer studies. The RWP is configured to run in two main operating modes: a precipitation (PR) mode with frequent vertical observations and a boundary layer (BL) mode that is similar to what has been traditionally applied to RWPs. To address issues regarding saturation of the radar signal, range resolution and maximum range, the RWP PR mode is set to operate with two different pulse lengths, termed as short pulse (SP) and long pulse (LP). Please refer to the RWP handbook (Coulter, 2012) for further information. Data from the RWP PR-SP and PR-LP modes have been extensively used to study deep precipitating clouds, especially their dynamical structure as the RWP data does not suffer from signal attenuation during these conditions (Giangrande et al., 2013). Tridon et al. (2013) used the data collected during the Mid-latitude Continental Convective Cloud Experiment (MC3E) to improve the estimation of noise floor of the RWP recorded Doppler spectra.

  14. GEOPHYSICAL RESEARCH LETTERS, VOL. 26, NO. 15, PAGES 2303-2306, AUGUST 1, 1999 Subsidence of Campi Flegrei (Italy) detected by SAR

    E-Print Network [OSTI]

    Beauducel, François

    Vesuviano, Napoli - Italy Abstract. Seven ERS SAR images of the Napoli area ac- quired from 1993 to 1996- ing of several environmental phenomena. High spatial sam- pling (with decametre ground resolution

  15. A 12b 50MS/s 2.1mW SAR ADC with redundancy and digital background calibration

    E-Print Network [OSTI]

    Chang, Albert H.

    A 12-bit 50MS/s SAR ADC implemented in 65nm CMOS technology is presented. The design employs redundancy to relax the DAC settling requirement and to provide sufficient room for errors such that the static nonlinearity ...

  16. Debris-less method and apparatus for forming apertures in hollow metallic articles

    DOE Patents [OSTI]

    Jordan, C.L.; Chodelka, E.J.

    1980-06-24T23:59:59.000Z

    This invention is a method for forming an aperture in a wall of a hollow metallic article without introducing metallic debris therein. In a typical operation, an annular groove is formed in an exterior portion of the wall. The groove defines an annular wall segment, and the bottom of the groove is shaped to slope downwardly away from the segment to form a tapered annular web which connects the segment to the wall. Any suitable coupling is attached to the outer face of the segment, as by welding. Pull then is applied to the coupling to effect circumferential breakage of the web, thus forming a removable single-piece wall fragment consisting of the web and segment. The fragment and the coupling member attached thereto then are removed from the wall.

  17. Direct imaging with highly diluted apertures. I. Field of view limitations

    E-Print Network [OSTI]

    O. Lardiere; F. Martinache; F. Patru

    2006-12-04T23:59:59.000Z

    Future optical interferometric instrumentation mainly relies on the availability of an efficient cophasing system: once available, what has so far postponed the relevance of direct imaging with an interferometer will vanish. This paper focuses on the actual limits of snapshot imaging, inherent to the use of a sparse aperture: the number of telescopes and the geometry of the array impose the maximum extent of the field of view and the complexity of the sources. A second limitation may arise from the beam combination scheme. Comparing already available solutions, we show that the so called hypertelescope mode (or densified pupil) is ideal. By adjusting the direct imaging field of view to the useful field of view offered by the array, the hypertelescope makes an optimal use of the collected photons. It optimizes signal to noise ratio, drastically improves the luminosity of images and makes the interferometer compatible with coronagraphy, without inducing any loss of useful field of view.

  18. Development of a Large Aperture Nb3Sn Racetrack Quadrupole Magnet

    SciTech Connect (OSTI)

    Ferracin, Paolo; Bartlett, Scott E.; Caspi, Shlomo; Dietderich, Daniel R.; Gourlay, Steve A.; Hannaford, Charles R.; Hafalia, Aurelio R.; Lietzke, Alan F.; Mattafirri, Sara; McInturff, Alfred D.; Nyman, Mark; Sabbi, Gianluca

    2005-06-01T23:59:59.000Z

    The U.S. LHC Accelerator Research Program (LARP), a collaboration between BNL, FNAL, LBNL, and SLAC, has among its major objectives the development of advanced magnet technology for an LHC luminosity upgrade. The LBNL Superconducting Magnet Group supports this program with a broad effort involving design studies, Nb{sub 3}Sn conductor development, mechanical models, and basic prototypes. This paper describes the development of a large aperture Nb{sub 3}Sn racetrack quadrupole magnet using four racetrack coils from the LBNL Subscale Magnet (SM) Program. The magnet provides a gradient of 95 T/m in a 110 mm bore, with a peak field in the conductor of 11.2 T. The coils are pre-stressed by a mechanical structure based on a pre-tensioned aluminum shell, and axially supported with aluminum rods. The mechanical behavior has been monitored with strain gauges and the magnetic field has been measured. Results of the test are reported and analyzed.

  19. Operating Water Cherenkov Detectors in high altitude sites for the Large Aperture GRB Observatory

    E-Print Network [OSTI]

    Allard, D; Asorey, H; Barros, H; Bertou, X; Castillo, M; Chirinos, J M; De Castro, A; Flores, S; González, J; Berisso, M Gomez; Grajales, J; Guada, C; Day, W R Guevara; Ishitsuka, J; López, J A; Martínez, O; Melfo, A; Meza, E; Loza, P Miranda; Barbosa, E Moreno; Murrugarra, C; Núñez, L A; Ormachea, L J Otiniano; Pérez, G; Perez, Y; Ponce, E; Quispe, J; Quintero, C; Rivera, H; Rosales, M; Rovero, A C; Saavedra, O; Salazar, H; Tello, J C; Peralda, R Ticona; Varela, E; Velarde, A; Villaseñor, L; Wahl, D; Zamalloa, M A

    2009-01-01T23:59:59.000Z

    Water Cherenkov Detectors (WCD) are efficient detectors for detecting GRBs in the 10 GeV - 1 TeV energy range using the single particle technique, given their sensitivity to low energy secondary photons produced by high energy photons when cascading in the atmosphere. The Large Aperture GRB Observatory (LAGO) operates arrays of WCD in high altitude sites (above 4500 m a.s.l.) in Bolivia, Mexico and Venezuela, with planned extension to Peru. Details on the operation and stability of these WCD in remote sites with high background rates of particles will be detailed, and compared to simulations. Specific issues due to operation at high altitude, atmospheric effects and solar activity, as well as possible hardware enhancements will also be presented.

  20. N d'ordre : 4079 ANNE 2009 THSE/UNIVERSITDERENNES1

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    unfocussed radar echoes and that gridded corner reflectors may serve as radiometric calibrators of dual . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 SAR remote sensing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.2.1 SAR polarimetry . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.2.2 SAR interferometry

  1. Nuclear Instruments and Methods in Physics Research A 474 (2001) 273284 Optimal coded aperture patterns for improved SNR in nuclear

    E-Print Network [OSTI]

    Schettini, Raimondo

    2001-01-01T23:59:59.000Z

    Nuclear Instruments and Methods in Physics Research A 474 (2001) 273­284 Optimal coded aperture patterns for improved SNR in nuclear medicine imaging Roberto Accorsia , Francesca Gasparinib , Richard C. Lanzaa, * a Nuclear Engineering Department, Massachusetts Institute of Technology, Room NW13-221, 77

  2. 2010 OPTICS LETTERS / Vol. 27, No. 22 / November 15, 2002 Study of an ultrahigh-numerical-aperture fiber continuum

    E-Print Network [OSTI]

    Oldenburg, Amy

    -numerical-aperture fiber continuum generation source for optical coherence tomography Daniel L. Marks, Amy L. Oldenburg and a practical enhancement to a fiber-optic optical coherence tomography system. © 2002 Op- tical Society custom-made optical components or specialized fibers that are not mass produced or readily available

  3. Synthetic Aperture and 3D Imaging for Mine Hunting Sonar F. Florin F. Fohanno I. Quidu J.-P. Malkasse

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    for various existing systems as hull mounted sonar and unmanned underwater vehicles : synthetic aperture.-P. Malkasse Thales Underwater Systems Route de sainte Anne du Portzic, CS 43814, 29238 Brest cedex 3, France to an acceptable level. These MCM operations require resources (sonar, sweep, vehicle,...) that are necessary

  4. The Effect of Oversampling on Aperture Jitter in Bandpass Sampling M. Patel, J. J. O'Reilly

    E-Print Network [OSTI]

    Haddadi, Hamed

    The Effect of Oversampling on Aperture Jitter in Bandpass Sampling Receivers M. Patel, J. J. O jitter limit sampling at high carrier frequencies. This paper investigates the effects of jitter on the effects of jitter. 1 Introduction. Wireless communications receivers have generally adopted

  5. Design and evaluation of a variable aperture collimator for conformal radiotherapy of small animals using a microCT scanner

    SciTech Connect (OSTI)

    Graves, Edward E.; Zhou Hu; Chatterjee, Raja; Keall, Paul J.; Gambhir, Sanjiv Sam; Contag, Christopher H.; Boyer, Arthur L. [Department of Radiology Oncology, Molecular Imaging Program at Stanford, Stanford University, Stanford, California 94305 (United States); Department of Mechanical Engineering, Molecular Imaging Program at Stanford, Stanford University, Stanford, California 94305 (United States); Department of Radiology Oncology, Molecular Imaging Program at Stanford, Stanford University, Stanford, California 94305 (United States); Department of Radiology, Molecular Imaging Program at Stanford, Stanford University, Stanford, California 94305 (United States); Department of Radiology, Scott and White Hospital, Temple, Texas 76508 (United States)

    2007-11-15T23:59:59.000Z

    Treatment of small animals with radiation has in general been limited to planar fields shaped with lead blocks, complicating spatial localization of dose and treatment of deep-seated targets. In order to advance laboratory radiotherapy toward what is accomplished in the clinic, we have constructed a variable aperture collimator for use in shaping the beam of microCT scanner. This unit can image small animal subjects at high resolution, and is capable of delivering therapeutic doses in reasonable exposure times. The proposed collimator consists of two stages, each containing six trapezoidal brass blocks that move along a frame in a manner similar to a camera iris producing a hexagonal aperture of variable size. The two stages are offset by 30 deg. and adjusted for the divergence of the x-ray beam so as to produce a dodecagonal profile at isocenter. Slotted rotating driving plates are used to apply force to pins in the collimator blocks and effect collimator motion. This device has been investigated through both simulation and measurement. The collimator aperture size varied from 0 to 8.5 cm as the driving plate angle increased from 0 to 41 deg. . The torque required to adjust the collimator varied from 0.5 to 5 N{center_dot}m, increasing with increasing driving plate angle. The transmission profiles produced by the scanner at isocenter exhibited a penumbra of approximately 10% of the collimator aperture width. Misalignment between the collimator assembly and the x-ray source could be identified on the transmission images and corrected by adjustment of the collimator location. This variable aperture collimator technology is therefore a feasible and flexible solution for adjustable shaping of radiation beams for use in small animal radiotherapy as well as other applications in which beam shaping is desired.

  6. Ultra-wideband short-pulse radar with range accuracy for short range detection

    DOE Patents [OSTI]

    Rodenbeck, Christopher T; Pankonin, Jeffrey; Heintzleman, Richard E; Kinzie, Nicola Jean; Popovic, Zorana P

    2014-10-07T23:59:59.000Z

    An ultra-wideband (UWB) radar transmitter apparatus comprises a pulse generator configured to produce from a sinusoidal input signal a pulsed output signal having a series of baseband pulses with a first pulse repetition frequency (PRF). The pulse generator includes a plurality of components that each have a nonlinear electrical reactance. A signal converter is coupled to the pulse generator and configured to convert the pulsed output signal into a pulsed radar transmit signal having a series of radar transmit pulses with a second PRF that is less than the first PRF.

  7. 915-MHz Radar Wind Profiler (915RWP) Handbook

    SciTech Connect (OSTI)

    Coulter, R

    2005-01-01T23:59:59.000Z

    The 915 MHz radar wind profiler/radio acoustic sounding system (RWP/RASS) measures wind profiles and backscattered signal strength between (nominally) 0.1 km and 5 km and virtual temperature profiles between 0.1 km and 2.5 km. It operates by transmitting electromagnetic energy into the atmosphere and measuring the strength and frequency of backscattered energy. Virtual temperatures are recovered by transmitting an acoustic signal vertically and measuring the electromagnetic energy scattered from the acoustic wavefront. Because the propagation speed of the acoustic wave is proportional to the square root of the virtual temperature of the air, the virtual temperature can be recovered by measuring the Doppler shift of the scattered electromagnetic wave.

  8. Digital hf radar observations of equatorial spread-F

    SciTech Connect (OSTI)

    Argo, P.E.

    1984-01-01T23:59:59.000Z

    Modern digital ionosondes, with both direction finding and doppler capabilities can provide large scale pictures of the Spread-F irregularity regions. A morphological framework has been developed that allows interpretation of the hf radar data. A large scale irregularity structure is found to be nightward of the dusk terminator, stationary in the solar reference frame. As the plasma moves through this foehn-wall-like structure it descends, and irregularities may be generated. Localized upwellings, or bubbles, may be produced, and they drift with the background plasma. The spread-F irregularity region is found to be best characterized as a partly cloudy sky, due to the patchiness of the substructures. 13 references, 16 figures.

  9. Phase coded, micro-power impulse radar motion sensor

    DOE Patents [OSTI]

    McEwan, T.E.

    1996-05-21T23:59:59.000Z

    A motion sensing, micro-power impulse radar MIR impresses on the transmitted signal, or the received pulse timing signal, one or more frequencies lower than the pulse repetition frequency, that become intermediate frequencies in a ``IF homodyne`` receiver. Thus, many advantages of classical RF receivers can be thereby be realized with ultra-wide band radar. The sensor includes a transmitter which transmits a sequence of electromagnetic pulses in response to a transmit timing signal at a nominal pulse repetition frequency. A receiver samples echoes of the sequence of electromagnetic pulses from objects within the field with controlled timing, in response to a receive timing signal, and generates a sample signal in response to the samples. A timing circuit supplies the transmit timing signal to the transmitter and supplies the receive timing signal to the receiver. The relative timing of the transmit timing signal and the receive timing signal is modulated between a first relative delay and a second relative delay at an intermediate frequency, causing the receiver to sample the echoes such that the time between transmissions of pulses in the sequence and samples by the receiver is modulated at the intermediate frequency. Modulation may be executed by modulating the pulse repetition frequency which drives the transmitter, by modulating the delay circuitry which controls the relative timing of the sample strobe, or by modulating amplitude of the transmitted pulses. The electromagnetic pulses will have a nominal center frequency related to pulse width, and the first relative delay and the second relative delay between which the timing signals are modulated, differ by less than the nominal pulse width, and preferably by about one-quarter wavelength at the nominal center frequency of the transmitted pulses. 5 figs.

  10. Lightning and radar observations of hurricane Rita landfall

    SciTech Connect (OSTI)

    Henderson, Bradley G [Los Alamos National Laboratory; Suszcynsky, David M [Los Alamos National Laboratory; Hamlin, Timothy E [Los Alamos National Laboratory; Jeffery, C A [Los Alamos National Laboratory; Wiens, Kyle C [TEXAS TECH U.; Orville, R E [TEXAS A& M

    2009-01-01T23:59:59.000Z

    Los Alamos National Laboratory (LANL) owns and operates an array of Very-Low Frequency (VLF) sensors that measure the Radio-Frequency (RF) waveforms emitted by Cloud-to-Ground (CG) and InCloud (IC) lightning. This array, the Los Alamos Sferic Array (LASA), has approximately 15 sensors concentrated in the Great Plains and Florida, which detect electric field changes in a bandwidth from 200 Hz to 500 kHz (Smith et al., 2002). Recently, LANL has begun development of a new dual-band RF sensor array that includes the Very-High Frequency (VHF) band as well as the VLF. Whereas VLF lightning emissions can be used to deduce physical parameters such as lightning type and peak current, VHF emissions can be used to perform precise 3d mapping of individual radiation sources, which can number in the thousands for a typical CG flash. These new dual-band sensors will be used to monitor lightning activity in hurricanes in an effort to better predict intensification cycles. Although the new LANL dual-band array is not yet operational, we have begun initial work utilizing both VLF and VHF lightning data to monitor hurricane evolution. In this paper, we present the temporal evolution of Rita's landfall using VLF and VHF lightning data, and also WSR-88D radar. At landfall, Rita's northern eyewall experienced strong updrafts and significant lightning activity that appear to mark a transition between oceanic hurricane dynamics and continental thunderstorm dynamics. In section 2, we give a brief overview of Hurricane Rita, including its development as a hurricane and its lightning history. In the following section, we present WSR-88D data of Rita's landfall, including reflectivity images and temporal variation. In section 4, we present both VHF and VLF lightning data, overplotted on radar reflectivity images. Finally, we discuss our observations, including a comparison to previous studies and a brief conclusion.

  11. Phase coded, micro-power impulse radar motion sensor

    DOE Patents [OSTI]

    McEwan, Thomas E. (Livermore, CA)

    1996-01-01T23:59:59.000Z

    A motion sensing, micro-power impulse radar MIR impresses on the transmitted signal, or the received pulse timing signal, one or more frequencies lower than the pulse repetition frequency, that become intermediate frequencies in a "IF homodyne" receiver. Thus, many advantages of classical RF receivers can be thereby be realized with ultra-wide band radar. The sensor includes a transmitter which transmits a sequence of electromagnetic pulses in response to a transmit timing signal at a nominal pulse repetition frequency. A receiver samples echoes of the sequence of electromagnetic pulses from objects within the field with controlled timing, in response to a receive timing signal, and generates a sample signal in response to the samples. A timing circuit supplies the transmit timing signal to the transmitter and supplies the receive timing signal to the receiver. The relative timing of the transmit timing signal and the receive timing signal is modulated between a first relative delay and a second relative delay at an intermediate frequency, causing the receiver to sample the echoes such that the time between transmissions of pulses in the sequence and samples by the receiver is modulated at the intermediate frequency. Modulation may be executed by modulating the pulse repetition frequency which drives the transmitter, by modulating the delay circuitry which controls the relative timing of the sample strobe, or by modulating amplitude of the transmitted pulses. The electromagnetic pulses will have a nominal center frequency related to pulse width, and the first relative delay and the second relative delay between which the timing signals are modulated, differ by less than the nominal pulse width, and preferably by about one-quarter wavelength at the nominal center frequency of the transmitted pulses.

  12. 1. INTRODUCTION It is important for most scientific analysis that how much radar energy reflects

    E-Print Network [OSTI]

    Howat, Ian M.

    the radiometric calibration of ASF (Alaska SAR Facility) processed RADARSAT product over the Antarctic Ice Sheet back from objects on the Earth. The procedure known as radiometric calibration is usually done by deciding calibration weights from corner reflectors and transponders. This report is for verifying

  13. The Design and Development of a Hybrid RF/Laser Radar System for Measuring Changes in

    E-Print Network [OSTI]

    Kansas, University of

    transmit power and higher PRF. RF pulse compression is used to improve system performance further. Receiver compression. Compared to laser radars like GLAS and MOLA, this sensor requires a lower peak transmit power Compression .......................................................... 14 2.6 Coherent Integration

  14. Ground penetrating radar technique to locate coal mining related features: case studies in Texas 

    E-Print Network [OSTI]

    Save, Neelambari R

    2006-04-12T23:59:59.000Z

    The goal of this research project is to identify the efficacy of the ground penetrating radar (GPR) technique in locating underground coal mine related subsidence features at Malakoff and Bastrop, Texas. The work at Malakoff ...

  15. Assessing and Analyzing Near-Surface Radar Snow Accumulation Layers at Summit, Greenland

    E-Print Network [OSTI]

    Overly, Thomas Buckmaster

    2010-04-28T23:59:59.000Z

    depth are compared to physical properties, age-depth relationships, and accumulation rates from ice cores near Summit. Having established the radar horizons as annual accumulation markers, a 350-year record of accumulation rate is derived and analyzed...

  16. A census of precipitation features in the tropics using TRMM: radar, ice scattering, and lightning observations

    E-Print Network [OSTI]

    Nesbitt, Stephen William

    1999-01-01T23:59:59.000Z

    and two ocean regions during August, September and October 1998, this study used radar retrievals and 85 GHz Polarization Corrected Temperatures (PCTs, which passively measure relative concentrations of precipitation-sized ice particles within a cloud...

  17. Development of an electronically tunable ultra-wideband radar imaging sensor and its components

    E-Print Network [OSTI]

    Han, Jeongwoo

    2006-08-16T23:59:59.000Z

    Novel microwave transmitter and receiver circuits have been developed for implementing UWB (Ultra-Wideband) impulse radar imaging sensor operating in frequency band 0.2 to 4 GHz. with tunable operating frequency band. The fundamental system design...

  18. Weather Radar and Hydrology 1 Influence of rainfall spatial variability on hydrological modelling: a

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Weather Radar and Hydrology 1 Influence of rainfall spatial variability on hydrological modelling variability as well as characteristics and hydrological behavior of catchments, we have proceeded simulator and a distributed hydrological model (with four production functions and a distributed transfer

  19. E-Print Network 3.0 - acquisition regime radar Sample Search...

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

    except the data acquisition system and the controller unit... A New Coherent Radar for Ice Sounding in Greenland A. Moussessian 1 , R.L. Jordan 1 , E. Rodriguez... : (818)...

  20. Radar-Based Vehicle Detection for Four-Quadrant Gate Crossing

    E-Print Network [OSTI]

    Illinois at Urbana-Champaign, University of

    · Work Crew Safety · Maximize Coverage · Longer Life · Immunity to Elements · Reliability · Potential Implementation #12;AREMA Compliance per Class C Equipment Environmental - Temperature, Humidity, Mechanical, EMI (Trackers) to Configuration Application Add Dual Radar Tracking Metrics Reliability Enhancements Accelerate

  1. 12B.4 2010 PHASEDARRAY RADAR INNOVATIVE SENSING EXPERIMENT Pam Heinselman 1

    E-Print Network [OSTI]

    Sensing Experiment (PARISE) via two components: radar data collection and National Weather Service (NWS." This sampling approach provides denser sampling at low altitudes, where it is needed most. In PARISE 2010

  2. Millimeter-wave radar sensor for automotive intelligent cruise control (ICC)

    SciTech Connect (OSTI)

    Russell, M.E.; Crain, A.; Curran, A.; Campbell, R.A.; Drubin, C.A.; Miccioli, W.F. [Raytheon, Tewksbury, MA (United States)] [Raytheon, Tewksbury, MA (United States)

    1997-12-01T23:59:59.000Z

    If automotive intelligent cruise-control (ICC) systems are to be successful in the marketplace, they must provide robust performance in a complex roadway environment. Inconveniences caused by reduced performance during inclement weather, interrupted performance due to dropped tracks, and annoying nuisance alarms will not be tolerated by the consumer, and would likely result in the rejection of this technology in the marketplace. An all-weather automotive millimeter-wave (MMW) radar sensor is described that uses a frequency-modulation coplanar-wave (FMCW) radar design capable of acquiring and tracking all obstacles in its field of view. Design tradeoffs are discussed and radar-sensor test results are presented along with the applicability of the radar to collision-warning systems.

  3. EFFICIENT ASSIMILATION OF RADAR DATA AT HIGH RESOLUTION FOR SHORT-RANGE NUMERICAL WEATHER PREDICTION

    E-Print Network [OSTI]

    Xue, Ming

    system must assimilate Doppler radar data including radial velocity and reflectivity, and combine and also con- tain the hydrometeors and latent heating effects that eliminate the need for spinning up

  4. On the Feasibility of Precisely Measuring the Properties of a Precipitating Cloud with a Weather Radar

    E-Print Network [OSTI]

    Runnels, R.C.

    In this paper the results of an investigation are presented that are concerned with the feasibility of employing a weather radar to make precise measurements of the properties of a precipitating cloud. A schematic cloud is proposed as a model...

  5. Ground penetrating radar characterization of wood piles and the water table in Back Bay, Boston

    E-Print Network [OSTI]

    LeFrançois, Suzanne O'Neil, 1980-

    2003-01-01T23:59:59.000Z

    Ground penetrating radar (GPR) surveys are performed to determine the depth to the water table and the tops of wood piles beneath a residential structure at 122 Beacon Street in Back Bay, Boston. The area of Boston known ...

  6. Radar and lightning analyses of gigantic jet-producing storms Tiffany C. Meyer,1,2

    E-Print Network [OSTI]

    Rutledge, Steven

    Radar and lightning analyses of gigantic jet-producing storms Tiffany C. Meyer,1,2 Timothy J. Lang of gigantic jets, similar to prior modeling studies. Citation: Meyer, T. C., T. J. Lang, S. A. Rutledge, W. A

  7. Multiple-scattering in radar systems: A review Alessandro Battaglia a,b,, Simone Tanelli c

    E-Print Network [OSTI]

    Hogan, Robin

    Review Multiple-scattering in radar systems: A review Alessandro Battaglia a,b,Ã, Simone Tanelli c. Tel.: +44 116 2709859. E-mail address: a.battaglia@le.ac.uk (A. Battaglia). Journal of Quantitative Spectroscopy & Radiative Transfer ] (

  8. Ground penetrating radar technique to locate coal mining related features: case studies in Texas

    E-Print Network [OSTI]

    Save, Neelambari R

    2006-04-12T23:59:59.000Z

    The goal of this research project is to identify the efficacy of the ground penetrating radar (GPR) technique in locating underground coal mine related subsidence features at Malakoff and Bastrop, Texas. The work at Malakoff has been done...

  9. Real-time 3-d localization using radar and passive surface acoustic wave transponders

    E-Print Network [OSTI]

    LaPenta, Jason Michael

    2007-01-01T23:59:59.000Z

    This thesis covers ongoing work into the design, fabrication, implementation, and characterization of novel passive transponders that allow range measurements at short range and at high update rates. Multiple RADAR measurement ...

  10. Thickness estimation of subsurface layers in asphalt pavement using monstatic ground penetrating radar

    E-Print Network [OSTI]

    Lau, Chun Lok

    1991-01-01T23:59:59.000Z

    for the degree of MASTER OF SCIENCE December 1991 Major Subject: Electrical Engineering THICKNESS ESTIMATION OF SUBSURFACE LAYERS IN ASPHALT PAVEMENT USING MONSTATIC GROUND PENETRATING RADAR A Thesis CHUN LOK LAU Approved as to style and content by... ACKNOWLEDGEMENTS. LIST OF FIGURES. . CHAPTER I INTRODUCTION. 1. 1 Importance of pavement profile data. 1. 2 Principle of Ground Penetrating Radar (GPR) . . . 1. 3 Subsurface layer thickness measurement method. . . . . . II GPR ANTENNA AND SYSTEM CALIBRATION...

  11. Laser radar VI; Proceedings of the Meeting, Los Angeles, CA, Jan. 23-25, 1991

    SciTech Connect (OSTI)

    Becherer, R.J.

    1991-01-01T23:59:59.000Z

    Topics presented include lidar wind shear detection for commercial aircraft, centroid tracking of range-Doppler images, an analytic approach to centroid performance analysis, simultaneous active/passive IR vehicle detection, and resolution limits for high-resolution imaging lidar. Also presented are laser velocimetry applications, the application of laser radar to autonomous spacecraft landing, 3D laser radar simulation for autonomous spacecraft landing, and ground based CW atmospheric Doppler lidar performamce modeling.

  12. The effect of smoothing the Doppler radar derived wind field on perturbation pressure retrieval

    E-Print Network [OSTI]

    Rosser, George Philip

    1986-01-01T23:59:59.000Z

    THE EFFECT OF SMOOTHING THE DOPPLER RADAR DERIVED WIND FIELD ON PERTURBATION PRESSURE RETRIEVAL A Thesis by GEORGE PHILIP ROSSER, JR. Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE May 1986 Major Subject: Meteorology THE EFFECT OF SMOOTHING THE DOPPLER RADAR DERIVED WIND FIELD ON PERTURBATION PRESSURE RETRIEVAL A Thesis by GEORGE PHILIP ROSSER, JR. Approved as to style and content by...

  13. Assessing the capabilities of ground penetrating radar for applications in geologic and engineering subsurface studies

    E-Print Network [OSTI]

    Servos, Stacia Lynn

    1998-01-01T23:59:59.000Z

    of different display parameters from GSSI's RADAN software package . . . 21 (a) Unfiltered radar profile over an underground storage tank. (b) Profile (a) has been filtered wdth a horizontal high pass boxcar filter, removing the long horizontal reflector... and processed in the laboratory using RADAN, interpretation software developed by GSSI. The radar profile (or radargram) seen on the computer screen is a composition of paraUel series of amplitude versus time. The darkness or color displayed is proportional...

  14. Some effects of range upon AN/CPS-9 radar reflectivities in thunderstorms

    E-Print Network [OSTI]

    Sanford, Tom E

    1961-01-01T23:59:59.000Z

    SOMB BFFBCTS OF RANGE UPON AN/CPS-9 RADAR RBFLECTIVITIBS IN THUNDBRSTORMS A Thesis Tommy Eugene Sanford Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE January 1961 Major Subject: Meteorology SOME EFFECI'S OF RANGE UPON AN/CPS-9 RADAR REFLECTIVITIES IN THUNDERSTORMS A Thesis Tommy Eugene Sanford Approved as to style and content by: (Chairman of Committe ) 4~4 (Head...

  15. A new clustering algorithm applicable to multispectral and polarimetric SAR images

    SciTech Connect (OSTI)

    Wong, Y.F. (Lawrence Livermore National Lab., CA (United States). Inst. for Scientific Computing Research); Posner, E.C. (California Inst. of Tech., Pasadena, CA (United States). Dept. of Electrical Engineering)

    1993-05-01T23:59:59.000Z

    The authors describe an application of a scale-space clustering algorithm to the classification of a multispectral and polarimetric SAR image of an agricultural site. After the initial polarimetric and radiometric calibration and noise cancellation, the authors extracted a 12-dimensional feature vector for each pixel from the scattering matrix. The clustering algorithm was able to partition a set of unlabeled feature vectors from 13 selected sites, each site corresponding to a distinct crop, into 13 clusters without any supervision. The cluster parameters were then used to classify the whole image. The classification map is much less noisy and more accurate than those obtained by hierarchical rules. Starting with every point as a cluster, the algorithm works by melting the system to produce a tree of clusters in the scale space. It can cluster data in any multidimensional space and is insensitive to variability in cluster densities, sizes and ellipsoidal shapes. This algorithm, more powerful than existing ones, may be useful for remote sensing for land use.

  16. Resonant bowtie aperture nano-antenna for the control of optical nanocavities resonance

    E-Print Network [OSTI]

    Baida, Fadi Issam

    2015-01-01T23:59:59.000Z

    Scanning Near-field Optical Microscopy (SNOM) has been successful in finely tuning the optical properties of photonic crystal (PC) nanocavities. The SNOM nanoprobes proposed so far allowed for either redshifting or blueshifting the resonance peak of the PC structures. In this Letter, we theoretically demonstrate the possibility of redshifting (up to +0.65nm) and blueshifting (up to $-5$~nm) PC cavity resonance with a single SNOM probe. This probe is obtained by opening a bowtie-aperture nano-antenna (BNA) at the apex of a metal-coated tip. This double-way PC tunability is the result of a competition between the effects of the BNA resonance (induced electric dipole leading to a redshift) and the metal-coated tip (induced magnetic dipole giving rise to a blueshift) onto the PC mode volume. The sign of the spectral shift is modified by simply controlling the tip-to-PC distance. This study opens the way to the full postproduction control of the resonance wavelength of high quality factor optical cavities.

  17. SNM neutron detection using a time-gated synthetic aperture hybrid approach

    SciTech Connect (OSTI)

    Molinar, M.; Yi, C.; Edgar, C. A.; Manalo, K.; Chin, M.; Sjoden, G. [Nuclear and Radiological Engineering Program, George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 770 State Street, Atlanta GA 30332-0745 (United States)

    2013-07-01T23:59:59.000Z

    This work focuses on using forward and adjoint transport in a hybrid application of 3-D deterministic (PENTRAN) and Monte Carlo (MCNP5) codes to model a series of neutron detector blocks. These blocks, or 'channels, ' contain a unique set of moderators with 4 atm He-3 detectors tuned to detect and profile a gross energy spectrum of a passing neutron (SNM) source. Ganging the units together as a large area system enables one to apply time gating the source-detector response to maximize signal to noise responses from a passing source with minimal background; multiple units may be positioned as a collective synthetic aperture detector array to be used as a way of performing real time neutron spectroscopy for detecting special nuclear materials in moving vehicles. The initial design, detector response coupling, confirmation of initial design functionality using adjoint transport calculations, and realistic simulation using PENTRAN and MCNP5 are presented. Future work will include optimization and application to realistic scenarios and additional sources. (authors)

  18. GPU-based ultra-fast direct aperture optimization for online adaptive radiation therapy

    E-Print Network [OSTI]

    Men, Chunhua; Jiang, Steve B

    2010-01-01T23:59:59.000Z

    Online adaptive radiation therapy (ART) has great promise to significantly reduce normal tissue toxicity and/or improve tumor control through real-time treatment adaptations based on the current patient anatomy. However, the major technical obstacle for clinical realization of online ART, namely the inability to achieve real-time efficiency in treatment re-planning, has yet to be solved. To overcome this challenge, this paper presents our work on the implementation of an intensity modulated radiation therapy (IMRT) direct aperture optimization (DAO) algorithm on graphics processing unit (GPU) based on our previous work on CPU. We formulate the DAO problem as a large-scale convex programming problem, and use an exact method called column generation approach to deal with its extremely large dimensionality on GPU. Five 9-field prostate and five 5-field head-and-neck IMRT clinical cases with 5\\times5 mm2 beamlet size and 2.5\\times2.5\\times2.5 mm3 voxel size were used to evaluate our algorithm on GPU. It takes onl...

  19. 3D synthetic aperture PIV measurements from artificial vibrating vocal folds

    E-Print Network [OSTI]

    Daily, Jesse; Belden, Jesse; Thomson, Scott; Truscott, Tadd

    2011-01-01T23:59:59.000Z

    During speech, air from the lungs is forced past the vocal folds which vibrate, producing sound. A pulsatile jet of air is formed downstream of the vibrating folds which interacts with the various structures in the airway. Currently, it is postulated that the way this jet interacts with the downstream structures in the airway directly affects the quality of human speech. In order to better understand this jet, it is desirable to visualize the jet in three dimensions. We present the results of a method that reconstructs the three dimensional velocity field using Synthetic aperture PIV (SAPIV) \\cite{Belden:2010}. SAPIV uses an array of high-speed cameras to artificially create a single camera with a variable focal length. This is accomplished by overlapping the images from the array to create a "focal stack". As the images are increasingly overlapped, more distant image planes come into focus. 3D PIV is then performed on the "refocused" focal stack to reconstruct the flow field in three dimensions. SAPIV has th...

  20. Analysis to determine the maximum dimensions of flexible apertures in sensored security netting products.

    SciTech Connect (OSTI)

    Murton, Mark; Bouchier, Francis A.; vanDongen, Dale T.; Mack, Thomas Kimball; Cutler, Robert Paul; Ross, Michael P.

    2013-08-01T23:59:59.000Z

    Although technological advances provide new capabilities to increase the robustness of security systems, they also potentially introduce new vulnerabilities. New capability sometimes requires new performance requirements. This paper outlines an approach to establishing a key performance requirement for an emerging intrusion detection sensor: the sensored net. Throughout the security industry, the commonly adopted standard for maximum opening size through barriers is a requirement based on square inches-typically 96 square inches. Unlike standard rigid opening, the dimensions of a flexible aperture are not fixed, but variable and conformable. It is demonstrably simple for a human intruder to move through a 96-square-inch opening that is conformable to the human body. The longstanding 96-square-inch requirement itself, though firmly embedded in policy and best practice, lacks a documented empirical basis. This analysis concluded that the traditional 96-square-inch standard for openings is insufficient for flexible openings that are conformable to the human body. Instead, a circumference standard is recommended for these newer types of sensored barriers. The recommended maximum circumference for a flexible opening should be no more than 26 inches, as measured on the inside of the netting material.