SAR Autofocus Algorithm of iterative error compensation based on PGA

This paper proposes a motion compensation algorithm based on PGA. Our algorithm first uses the PGA algorithm to estimate roughly the phase error of the SAR data, which is then exploited through several iterations to compensate for the phase error and the range migration caused by the motion error to obtain a focused SAR image. A single iteration not only improves the image quality, but also improves the motion error compensation accuracy of the PGA algorithm in the next iteration. The simulation and measured data show that the algorithm can effectively compensate the motion error with fast convergence speed, good SAR image focusing effect and high error compensation accuracy.