Research and Experimental Verification on High Sensitivity and High Stability Microwave Radiometer
NIU Lijie①② LIU Hao① WU Ji①
①(Key Laboratory of Microwave Remote Sensing, National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China) ②(University of Chinese Academy of Sciences, Beijing 100049, China)
Global measurement of ocean salinity using satellite borne synthetic aperture radiometer is one of the research focuses in the field of microwave remote sensing. In order to achieve the accuracy of the ocean salinity detection, the radiometer units of the synthetic aperture radiometer need to have very high sensitivity and very high calibration stability. In this paper, the technique of the radiometer with high sensitivity and high stability is researched. High stability is realized by the real-time calibration method, and the sensitivity is effectively improved by the calibration data average technology. The optimal average time is obtained by the frequency domain analysis for the first time. Long time stability experiments are completed to demonstrate its performance. Experimental results show that the stability of this L-band radiometer reaches 0.12 K (in 3 days), and the sensitivity reaches 0.1 K, which can reach the requirement of the synthetic aperture radiometer for ocean salinity detection.
牛立杰,刘浩,吴季. 高灵敏度、高稳定度微波辐射计技术研究与实验验证[J]. 电子与信息学报, 2017, 39(8): 2028-2032.
NIU Lijie, LIU Hao, WU Ji. Research and Experimental Verification on High Sensitivity and High Stability Microwave Radiometer. JEIT, 2017, 39(8): 2028-2032.
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