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The Upper Atmosphere Research Satellite microwave limb sounder instrumentThe microwave limb sounder (MLS) on the Upper Atmosphere Research Satellite (UARS) is the first satellite experiment using limb sounding techniques at microwave frequencies. Primary measurement objectives are stratospheric ClO, O3, H2O, temperature, and pressure. Measurements are of thermal emission: all are performed simultaneously and continuously and are not degraded by ice clouds or volcanic aerosols. The instrument has a 1.6-m mechanically scanning antenna system and contains heterodyne radiometers in spectral bands centred near 63, 183, and 205 GHz. The radiometers operate at ambient temperature and use Schottky-diode mixers with local oscillators derived from phase-locked Gunn oscillators. Frequency tripling by varactor multipliers generates the 183- and 205-GHz local oscillators, and quasi-optical techniques inject these into the mixers. Six 15-channel filter banks spectrally resolve stratospheric thermal emission lines and produce an output spectrum every 2 s. Thermal stability is sufficient for 'total power' measurements which do not require fast chopping. Radiometric calibration, consisting of measurements of cold space and an internal target, is performed every 65-s limb scan. Instrument in-orbit performance has been excellent, and all objectives are being met.
Document ID
19930061210
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Barath, F. T.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Chavez, M. C.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Cofield, R. E.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Flower, D. A.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Frerking, M. A.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Gram, M. B.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Harris, W. M.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Holden, J. R.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Jarnot, R. F.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Kloezeman, W. G.
(JPL Pasadena, CA, United States)
Date Acquired
August 16, 2013
Publication Date
June 20, 1993
Publication Information
Publication: Journal of Geophysical Research
Volume: 98
Issue: D6
ISSN: 0148-0227
Subject Category
Spacecraft Instrumentation
Accession Number
93A45207
Distribution Limits
Public
Copyright
Other

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