Optimal Scene Coordinate System for Geo SAR Focusing with Fast Time-Domain Algorithm

This paper focuses on developing the processing algorithm applicable to the GEO SAR especially at high squint. The analytic expressions of the squint-mode wavenumber support and point spreading function are derived. Then, we propose a generalized fast Cartesian factorized back-projection algorithm, which can deal with high-squint data, and the scene coordinate system can be built with high flexibility. Especially, the optimal scene coordinate system is exploited. Finally, processing results of simulated data are presented to validate the proposed algorithm.