Lifan Zhao, Lu Wang, Lei Yang, Abdelhak M. Zoubir, and Guoan Bi ©ISTOCKPHOTO.COM/MAKHNACH_M The Race to Improve Radar Imagery An overview of recent progress in statistical sparsity-based techniques T he exploitation of sparsity has significantly advanced the field of radar imaging over the last few decades, leading to substantial improvements in the resolution and quality of the processed images. More recent developments in compressed sensing (CS) suggest that statistical sparsity can lead to further performance benefits by imposing sparsity as a statistical prior on the considered signal. In this article, a comprehensive survey is made of recent progress on statistical sparsitybased techniques for various radar imagery applications. Introduction The capability of operating in all-day, all-night, and all-weather conditions has allowed high-resolution radar imagery to play an important role in both civilian Digital Object Identifier 10.1109/MSP.2016.2573847 Date of publication: 4 November 2016 1053-5888/16©2016IEEE IEEE SIgnal ProcESSIng MagazInE | November 2016 | 85http://www.ISTOCKPHOTO.COM/MAKHNACH_M