Sensitivity and response time improvements in a millimeter-wave spectrometer

Journal Article · Tue Jun 01 04:00:00 EDT 1982 · Rev. Sci. Instrum.; (United States)

DOI:https://doi.org/10.1063/1.1137061· OSTI ID:5505805

Kolbe, W F; Leskovar, B

An improved microwave spectrometer for the detection of gaseous pollutants and other atmospheric constituents is described. The spectrometer, which operates in the vicinity of 70 GHz, employs a Fabry--Perot resonator as a sample cell and uses superheterodyne detection for high sensitivity. The instrument has been modified to incorporate a frequency doubler modulated at 30 MHz to permit operation with a single Gunn oscillator source. As a result, faster response time and somewhat greater sensitivity are obtained. The spectrometer is capable of detecting a minimum concentration of 1 ppm of SO/sub 2/ diluted in air with a 1-s time constant. For OCS diluted in air, the minimum detectable concentration is 800 ppb and with a 10-s time constant 300 ppb.

• Research Organization: Lawrence Berkeley Laboratory, University of California, Berkeley, California 94720
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 5505805
• Journal Information: Rev. Sci. Instrum.; (United States), Journal Name: Rev. Sci. Instrum.; (United States) Vol. 53:6; ISSN RSINA
• Country of Publication: United States
• Language: English

Related Subjects

440300* -- Miscellaneous Instruments-- (-1989)
47 OTHER INSTRUMENTATION
AIR POLLUTION
CARBON COMPOUNDS
CARBON OXYSULFIDE
CHALCOGENIDES
EARTH ATMOSPHERE
ELECTRONIC EQUIPMENT
EQUIPMENT
FABRY-PEROT INTERFEROMETER
FLUIDS
FREQUENCY CONVERTERS
FREQUENCY RANGE
FUNCTIONS
GASES
GHZ RANGE
GHZ RANGE 100-1000
HETERODYNE RECEIVERS
INTERFEROMETERS
MEASURING INSTRUMENTS
MICROWAVE EQUIPMENT
MODULATION
OSCILLATORS
OXIDES
OXYGEN COMPOUNDS
POLLUTION
QUANTITY RATIO
RADIO EQUIPMENT
RESONATORS
RESPONSE FUNCTIONS
SENSITIVITY
SPECTROMETERS
SULFUR COMPOUNDS
SULFUR OXIDES