提出了一种基于数字聚束技术的PFA波前弯曲误差补偿新方法,该方法首先对回波数据进行两维空域滤波和降采样,将原始的宽波束大场景数据分解成若干窄的子波束子场景数据,再结合PFA的非共面运动补偿能力,能够有效解决在雷达任意航迹条件下的PFA波前弯曲误差补偿问题,显著提高PFA有效成像场景范围。仿真数据处理表明了算法的有效性。
In this paper,a new wavefront curvature compensation method based on digital spotlighting preprocessing is proposed.First,digital spotlighting preprocessing,filtering and downsampling in 2-dimensional space domain,is performed on echo data.This generates multiple full-resolution phase histories of smaller image patches,each corresponding to a narrow-beam phase history data where the wavefront curvature effect can be ignored.Due to the inherent non-planar motion compensation capability,PFA is used to produce focused fine resolution image for each small patch.Finally,all focused image patches are seamed together to get a full image.Simulation experiments show that the new algorithm has improved focused scene size when applying to phase history generated by non-ideal radar flight path.