Signatures of Moving Target in Spotlight SAR Imagery

The synthetic aperture radar (SAR) signatures of moving target are the basis of ground moving target detection imaging and relocation. However, previous studies are mainly based on the 2-D separable SAR processing, and little work has been done to investigate the signatures of moving target after the application of a particular fine resolution SAR image formation algorithm. In this paper, we derive the image spectrum of the moving target after representative fine resolution SAR image formation algorithm, i.e., the polar format algorithm (PFA), respectively. Based on the spectrum derived, the SAR signatures of moving targets are analyzed in detail, including the geometric displacement, and the defocusing effect. Finally the analytical results are verified via simulation data processing.