一种基于持续运动模型的星载SAR几何校正方法

摘要

几何校正是星载 SAR 地面处理的重要环节，几何校正精度对 SAR 图像的应用有着至关重要的影响。该文分析了传统星载SAR几何校正中卫星“停-走”模型近似对几何定位精度的影响，建立了卫星持续运动模型下的距离多普勒方程，并提出了持续运动模型下校正方程的简化求解方法。仿真实验和北京地区实际数据几何校正试验验证了该方法的有效性和正确性。%　　Geolocation is a very important step in Synthetic Aperture Radar (SAR) data processing. The precision of geolocation severely affects the applications of SAR images. This paper analyzes the influences on SAR geolocation caused by the traditional“stop-go”approximation, and establishes the range-Doppler equations for the real continuously moving configuration. It also provides a simplified way of solving the equations. Simulations and geolocation experiments on real SAR data of the Beijing area validate the proposed method and show the correctness of the analysis.