Processing of Spaceborne High-Resolution Sar Data with Curved Orbit

Abstract

A novel imaging algorithm is presented in this paper for focusing the very-high resolution spaceborne synthetic aperture radar (SAR) data of spotlight mode. First, the first step of two-steps processing approach (TSPA) is used to get a high azimuth sampling rate which is higher than PRF for the raw data. Then, the fast-time effect of stop-and-go approximation is corrected in 2-D frequency domain. Finally, the back-projection algorithm (BPA) is used to correct the error introduced by the curved orbit and the slow-time effect of stop-and-go approximation. The simulation results confirm that the proposed method has good performance. The spaceborne SAR data acquired by Gaofen-3 SAR systems demonstrate the feasibility of the proposed method.