Improved PGA algorithm based on adaptive range bins selection

Phase gradient autofocus (PGA) algorithm has been proved to be a superior method for higher order phase error correction in SAR/ISAR image post processing. However, the accuracy of phase error estimation using traditional PGA algorithm is usually not guaranteed especially when there are several strong adjacent scatterers in a range bin. In this paper an improved iterative PGA approach based on adaptive range bins selection is presented. Results of real data experiments show that the improved PGA algorithm outperforms the traditional one.