Atmospheric Humidity Sounding Using Differential Absorption Radar Near 183 GHz
| Autor: | Jose V. Siles, Andrew K. Brown, Simone Tanelli, Ken B. Cooper, Choonsup Lee, Luis Millán, Matthew Lebsock, Raquel Monje |
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| Rok vydání: | 2018 |
| Předmět: |
Materials science
010504 meteorology & atmospheric sciences business.industry Attenuation Transmitter 020206 networking & telecommunications 02 engineering and technology Geotechnical Engineering and Engineering Geology Noise figure 01 natural sciences law.invention Bistatic radar Depth sounding Optics Duplexer law 0202 electrical engineering electronic engineering information engineering Electrical and Electronic Engineering Radar Antenna gain business Physics::Atmospheric and Oceanic Physics 0105 earth and related environmental sciences |
| Zdroj: | IEEE Geoscience and Remote Sensing Letters. 15:163-167 |
| ISSN: | 1558-0571 1545-598X |
| DOI: | 10.1109/lgrs.2017.2776078 |
| Popis: | A tunable G-band frequency-modulated continuous-wave radar system has been developed and used to perform differential absorption atmospheric humidity measurements for the first time. The radar’s transmitter uses high- power-handling GaAs Schottky diodes to generate between 15–23 dBm over a 10-GHz bandwidth near 183 GHz. By virtue of a high-isolation circular polarization duplexer, the monostatic radar’s receiver maintains a noise figure of about 7 dB even while the transmitter is on. With an antenna gain of 40 dB, high-SNR detection of light rain is achieved out to several hundred meters distance. Owing to the strong spectral dependence of the atmospheric absorption over the upper flank of the 183-GHz water absorption line, range-resolved measurements of absolute humidity can be obtained by ratioing the rain echoes over both range and frequency. Absorption measurements obtained are consistent with models of atmospheric millimeter-wave attenuation, and they demonstrate a new method for improving the accuracy of humidity measurements inside of clouds. |
| Databáze: | OpenAIRE |
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