Improved Method of Video Synthetic Aperture Radar Imaging Algorithm

Video synthetic aperture radar (ViSAR) is a novel imaging model to persistently surveil the region of interest by a series of consecutive images in real time. The formation time of one frame image, which can influence the image latency, is one of the key factors to realize ViSAR system. In general, the polar format algorithm (PFA) is preferred for ViSAR imaging. However, the 2-D resampling in the PFA has a large computation burden and is complex to realize in the real-time processing system. It has become the main obstacle to reduce image latency. Therefore, we derive four judgment criteria in this letter. According to these criteria, we propose the improved method of the PFA. Based on this method, the modified PFA can reduce the image formation time while guaranteeing the image quality. Simulation results are presented to validate the effectiveness of the improved method proposed in this letter.