①Institute of Electronics, Chinese Academy of Sciences, Beijing 100080, China; ②Graduate School of the Chinese Academy of Sciences, Beijing 100039, China
Abstract:Sliding spotlight SAR is a novel mode of SAR imaging, which can improve azimuth resolution by controlling the speed of antenna footprint to increase coherent accumulation time. This paper analyzes the sliding-spotlight mode at the aspects of imaging principle, echo model, resolution, antenna operational mode, swath width, etc. And it presents the “wavenumber domain” algorithm of sliding-spotlight SAR. Compared with stripmap and spotlight SAR imaging, both stripmap and spotlight are special forms of sliding-spotlight mode.