一种变 PRF 双基 SAR 快速极坐标格式算法

摘要

极坐标格式算法(PFA)是双基聚束模式合成孔径雷达(SAR)成像中一种经典的成像算法，在聚束 SAR 系统中有着重要的意义。从信号二维解耦合的角度出发，进一步分析极坐标格式算法中距离向插值和方位向插值对目标距离徙动(RCM)的校正过程，给出了对双基 SAR 极坐标格式算法的一种新解释，并提出一种基于变脉冲重复频率(PRF)的双基 SAR 快速极坐标格式算法。该方法可以提高双基 SAR 极坐标格式算法的计算效率，扩大其应用范围。点目标仿真验证了该方法的有效性。%Polar format algorithm (PFA)is a classic algorithm for bistatic synthetic aperture radar (SAR)imaging and has important significance in spotlight bistatic SAR system.In this paper,we analyze the range and azimuth resampling procedures for their roles in range cell migration(RCM)correction from the viewpoint of two-dimensional decoupling and provide a new formulation of PFA for bistatic spotlight SAR.A fast polar format algorithm is proposed,which is based on variable pulse repetition frequency (PRF).This algorithm can improve the computation efficiency and expand the application range of PFA for bistatic SAR imaging.Point target simulation validates the algorithm.