Compact Polarimetric Synthetic Aperture Radar for Target Detection: A Review

In recent years, compact polarimetric (CP) SAR has been widely used for Earth target detection as a means to balance system resources and target information. Although there has been a large number of related researches, an in-depth review of CP SAR, from basic principles to target detection methods, is lacking. This article aims to provide a review of this area. In this article, we review the historical development and application status of CP SAR, introduce the basic principles and the target detection principles of CP SAR, and summarize the currently proposed methods for CP SAR target detection. Over 200 publications are covered. We also discuss the challenges of current research and point out three promising research directions, i.e., the further deepening of feature extraction, deeper understanding of target characteristics, and development of intelligent detection techniques. We hope that this survey will help researchers to better understand this research area.