基于非理想运动误差补偿的SAR地面运动目标成像

摘要

传统的SAR地面运动目标成像算法主要集中在距离徙动校正和目标的运动参数估计上。但在SAR实测数据处理中，非理想运动误差补偿对动目标聚焦成像质量至关重要，而且该误差既不能通过固定的SAR运动误差补偿算法来补偿，也无法通过采用自聚焦技术解决。该文根据含有非理想运动误差的SAR运动目标回波信号模型，对影响动目标多普勒中心的两类非理想运动误差进行深入分析，提出一种将INS惯导数据与距离走动轨迹相结合的非理想运动误差补偿算法，并通过实际数据和计算机仿真数据验证了该算法的有效性。%Conventional ground moving target imaging algorithms mainly focus on the range cell migration cor-rection and the motion parameter estimation of the moving target. However, in real Synthetic Aperture Radar (SAR) data processing, non-ideal motion error compensation is also a critical process, which focuses and has serious impacts on the imaging quality of moving targets. Non-ideal motion error can not be compensated by either the stationary SAR motion error compensation algorithms or the autofocus techniques. In this paper, two sorts of non-ideal motion errors that affect the Doppler centroid of the moving target is analyzed, and a novel non-ideal motion error compensation algorithm is proposed based on the Inertial Navigation System (INS) data and the range walk trajectory. Simulated and real data processing results are provided to demonstrate the ef-fectiveness of the proposed algorithm.