Results 231 to 240 of about 33,686 (258)

A Microwave Feedback Radiometer

IEEE Transactions on Aerospace and Electronic Systems, 1967
Two versions of a microwave feedback radiometer have been built and tested. One used an electromechanical feedback system; the other, an all-electronic system. The response of the servo loops proved to be fast enough and linear enough for almost any radiometer application. The rms noise fluctuation was the same as that of a Dicke radiometer.
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TRMM microwave radiometer algorithms

Proceedings of IGARSS '93 - IEEE International Geoscience and Remote Sensing Symposium, 2002
The TRMM Microwave Imager (TMI) is a modified SSM/I. Significant modifications include: the addition of 2 channels at 10.7 GHz (H and V polarization), a shift of the 22.235 GHz V channel to 21.4 GHz H, and increasing the cone angle from 45/spl deg/ to 49/spl deg/.
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SMAP Microwave Radiometer Calibration Revisit

IGARSS 2019 - 2019 IEEE International Geoscience and Remote Sensing Symposium, 2019
The SMAP L-band microwave radiometer has completed its 3-year primary mission of measuring soil moisture and freeze/thaw state globally for quantifying the water and carbon cyclces. Instrument behavior is stable over the past 3 years and 9 months.
Jinzheng Peng, Sidharth Misra, Jeffrey Piepmeier, Simon Yueh, Emmanuel Dinnat, David Le Vine, Thomas Meissner, Priscilla Mohammed   +7 more
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An imaging microwave radiometer†

International Journal of Remote Sensing, 1983
Abstract The phase A study of an imaging microwave radiometer (IMR) has been completed, for ESA, by a team of contractors led by BAe. The instrument design which was established during this study is described in this paper. The IMR would be able to measure the intensity of radiation in the microwave band at a number of specific frequencies.
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An electronically switched microwave radiometer

Journal of Physics D: Applied Physics, 1973
An 11·5 GHz microwave radiometer is described in which periodic noise variations up to 1 kHz were resolved by a sampling process using PIN diode switching. A sensitivity of 0·04 dB (100 K) was recorded in checking the system with the noise power emanating from a current-modulated plasma column.
C J Burkley, C P Downing, M C Sexton
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MetOp Second Generation Microwave radiometers

2012 12th Specialist Meeting on Microwave Radiometry and Remote Sensing of the Environment (MicroRad), 2012
This paper presents an overview of three Microwave radiometers currently studied for MetOp Second Generation by European Space Agency (ESA). The radiometers are Microwave Sounder (MWS), Microwave Imager (MWI) and Ice Cloud Imager (ICI).
Ville Kangas, Salvatore D'Addio, Maurizio Betto, Hubert Barre, Graeme Mason   +4 more
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Temperature resolution of microwave radiometers

Radiophysics and Quantum Electronics, 1997
We consider the quantum limits of the radiometer sensitivity in power and spectral density measurements of the radio emission. It is shown that taking into account zero-point field fluctuations makes it possible to resolve some paradoxes in the theory of an ideal radiometer.
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The ERS-1 microwave radiometer

International Journal of Remote Sensing, 1994
Abstract The microwave radiometer on board ERS-1 developed at CRPE has two channels at 23·8 and 36·5 GHz. It is a nadir pointing sensor, aimed at the correction of the altimeter tropospheric path delay. It also provides the precipitable water and cloud liquid water over oceans along the satellite track. However, the measured brightness temperatures can
L. EYMARD, A. LE CORNEC, L. TABARY
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Dual frequency microwave radiometer

2010
A dual-frequency microwave radiometer has been developed to remotely sense water vapor and liquid in the troposphere. An optimum frequency pair, 20.60 and 31.65 GHz, is adopted. The system consists of two Dicke radiometers (one at each frequency), both of which are controlled by a microcomputer system and mounted on a rotatable pedestal.
Yao, Zhuanliang, Zheng, Jiahao, Jin, Peiyu, Xu, Peiyuan, Zhao, Conglong, Fang, Zhenhuo, Li, MingXiang, Wang, Zhenrong, Lin, Bin   +8 more
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Microwave vegetation indices derived from satellite microwave radiometers

SPIE Proceedings, 2008
Vegetation indices are valuable in many fields of geosciences. Conventional, visible-near infrared, indices are often limited by the effects of atmosphere, background soil conditions, and saturation at high levels of vegetation. In this study, the theoretical basis for a new type of passive microwave vegetation indices (MVIs) based on data from the ...
T. J. Jackson, J. C. Shi, J. Tao
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