综合孔径微波辐射计信道误差分析与标定

本文首先建立了综合孔径微波辐射计的信道模型,在此基础上分析了信道的幅度相位不平衡以及信道间串扰对反演亮温的影响,并给出了系统仿真结果.本文还提出了一种新的系统定标方案,与传统定标方法相比,该方法可以非常方便的获取高精度的系统调制G矩阵用于亮温反演.

Analysis and Calibration of the Channels Error of Synthetic Aperture Radiometer

Theoretical channels model of synthetic aperture radiometer are pr esented.Based on this model,how amplitude imbalance,phase imbalance and mutual c oupling between the different receiving channels effect brightness temperature r etrieving is analyzed.The computer simulation results are also presented,in whic h the cause of the along-track streaks usually appeared in the retrieved image is identified.In addition,a new system calibration approach is introduced to sol ve this problem: using digital I-Q vector modulators to simulate the point sour ce in the antenna range,we can get more accurate G Matrix to retrieve the bright ness temperature image.This new approach,as compared with the existing calibrati on methods,is especially suitable for in situ use.