Focusing Azimuth Periodically Gapped SAR Raw Data Via Complex Fista with Suppressed Artificial Targets

Abstract

A novel algorithm is proposed in this paper to focus the azimuth periodically gapped Synthetic Aperture Radar (SAR) raw data with suppressed artificial targets. The proposed method mainly consists of phase compensation in range frequency domain, subsequent sparse recovery via complex Fast Iterative Shrinkage-Thresholding Algorithm (FISTA) and focusing recovered SAR data with traditional SAR imaging algorithm. With phase compensation, the gapped data becomes sparser in range Doppler domain and complex FISTA is utilized to restore complete data from gapped data in range Doppler domain. Afterwards, the conventional SAR focusing algorithms are capable of coping with the recovered data. The proposed method focuses azimuth gapped data with lower artificial targets and performs faster than method based on complex Iterative Shrinkage- Thresholding Algorithm (ISTA). In experiments, point target simulation and real SAR data processing are utilized to demonstrate the validity of the proposed method.