基于频谱偏移的GEO星机多基SAR提高距离分辨率方法

An Algorithm Based on Spectrum Shift for Improving Range Resolution Using GEO Spaceborne/Airborne Multistatic SAR

该文给出了发射端固定的单发多收地球同步轨道(GEO)星机多基SAR几何模型,推导了不同接收端回波之间的频谱偏移。基于该频谱偏移,提出了通过合成不同接收端的频谱实现提高距离分辨率的方法。详细分析了谱合成过程中产生的重叠干扰项,及其对距离分辨率的影响,并提出了权值滤波的方法进行抑制。最后通过仿真验证了方法的有效性。

In this paper,the GEO spaceborne/airborne multistatic SAR geometry model with one fixed transmitter and multiple receivers is proposed,and the spectrum shift between different receiver echoes is derived.Based on the spectrum shift,a new algorithm for improving range resolution of this model by composing spectrums of different receivers is proposed.The overlapped interference term,which is induced during spectrum composing,and its influence on range resolution,is analyzed in detail,and a method by weight filtering is provided to remove the interference term.Finally,simulation is employed to test validity of the algorithm.