基于欠定系统局灶解法的逆合成孔径雷达成像

摘要

In order to solve the problems of the existing signal reconstruction methods which have more or less defects such as big amount of calculation and needing the signal sparseness as the prior information,an improved method of ISAR imaging algorithm based on focal undetermined system solver was proposed.Of this method,conjugate gradient scheme based on QR decomposition was used to solve the linear equations in regularized focal undetermined system sol-ver (R-FOCUSS)method.Simulation results showed that it could obtain more clear imaging results and further im-proved the computing speed by using the improved method to reconstruct the received signal.%针对目前压缩感知中常用的信号重构算法普遍存在计算复杂、需要信号的稀疏度作为先验信息等缺陷的问题,提出了基于欠定系统局灶解法(Focal Undetermined System Solver,FOCUSS)的逆合成孔径雷达(Inversed Synthetic Aperture Radar,ISAR)成像方法。该方法利用 QR 分解预处理共轭梯度法求解正则化FOCUSS 算法中的线性方程组,在不需要先验信息的条件下进一步提高算法收敛速度。仿真实验表明,利用基于 QR 分解预处理共轭梯度法改进的正则化 FOCUSS 算法对回波信号进行重构,既能获得更加清晰的成像结果,又能进一步提高运算速度。