星载聚束式SAR子孔径成像处理方法

A SUBAPERTURE IMAGING APPROACH OF SPACEBORNE SPOTLIGHT SAR

该文分析了星载聚束式SAR的信号特性。在分析比较几种常见聚束式SAR成像算法的基础上,引入适用于星载聚束式SAR成像的改进chirp scaling算法。为解决高分辨率星载聚束式SAR具有的脉冲重复频率(PRF)过高,多普勒带宽中心频率时变性等问题,深入分析了采用子孔径方法的必要性及其实现方法,并将子孔径方法结合到chirp scaling算法中。最后,通过计算机仿真,验证了该算法适用于高分辨率星载聚束式SAR成像处理。

Signal properties of spaceborne spotlight SAR are discussed. Based on the analyses of a few spotlight imaging algorithm, a modified chirp scaling algorithm for spaceborne spotlight SAR is proposed. Besides, a subaperture method is combined with the algorithm. In order to resolve high Pulse Repetition Frequency (PRF) and the time-variant of Doppler center frequency, etc., the necessity and implementation approach of the subaperture method are analyzed thoroughly. The validity of the proposed method is tested by computer simulation.