Research on the near range imaging of Ground-based SAR system

In this article, a specific problem of Ground-based SAR (GB-SAR) system imaging is introduced. As for GB-SAR, the illuminated area ranges from about 1 m to 1000 m. As a result, the attenuation of the echo with the range change could not be ignored. At the same time, imaging algorithms processing airborne and space-borne echo data will overlook the attenuation, so normal algorithms have deficiency in processing echo under such condition. Aiming at this specific problem, an echo model considering the attenuation is given at first; and a simulated echo is processed using Range Migration Algorithm. Then, to make up the deficiency of RMA under this specific situation, a method based on confocal imaging theory is given and corresponding simulation result are presented. Finally, the confocal imaging method is validated via experiment of Ground-based SAR system.