Exact spectrum of non‐linear chirp scaling and its application in geosynchronous synthetic aperture radar imaging

Abstract

Non-linear chirp scaling (NLCS) is a feasible method to deal with time-variant frequency modulation (FM) rate problem in synthetic aperture radar (SAR) imaging. However, approximations in derivation of NLCS spectrum lead to performance decline in some cases. Presented is the exact spectrum of the NLCS function. Simulation with a geosynchronous synthetic aperture radar (GEO-SAR) configuration is implemented. The results show that using the presented spectrum can significantly improve imaging performance, and the NLCS algorithm is suitable for GEO-SAR imaging after modification.