综合孔径微波辐射计信道误差分析与标定-电子学报.pdf

3 Vol.33 No. 3 2005 3 ACTA ELECTRONICA SINICA Mar. 2005 刘 浩, 吴 季, 吴 琼 ( 863, 100080) : , , ., , G . : ; ; ; ; : TP722. 6 : A : (2005) Analysis and Calibration of the Channels Error of Synthetic Apert ure Radiometer LIU Hao,WU Ji, WU Qiong ( Centerf or Space Science and App lied Research, Chinese Academy of Sciences, Bejiing 100080, China) Abstract : T eoretical c annels model of synt etic aperture radiometer are presented. Based on t is model, ow amplitude imbal ance, p ase imbalance and mutual coupling between t e different receiving c annels effect brig tness temperature retrieving is analyzed. T e computer simulation results are also presented, in w ic t e cause of t e alongtrack streaks usually appeared in t e retrieved image is identified. In addition, a new system calibration approac is introduced to solve t is problem: using digital IQ vector modulators to simulate t e point source in t e antenna range,we can get more accurate G Matrix to retrieve t e brig tnesstemperature image.T is new approac , as comparedwit t e existing calibration met ods, is especially suitable for in situ use. Key words: synt etic aperture radiometer; imbalance; mutual coupling; calibration 1 , . , , , , . , 20 80 , , 50~ 60 , [ 1] , , . , . . . , 2 : , , . ; [ 1] IQ IQ ; , : . 1 , , . ,