A New Method for Bistatic SAR Imaging Based on Chirp-Z Transform

Abstract

Bistatic SAR (BiSAR) has the advantages of flexible platform configuration, the rich echo information and strong anti-jamming with the separate transmit-receive platform. Focusing bistatic SAR data in frequency domain requires two-dimensional (2D) point target spectrum. In the paper, the method of series reversion (MSR) is chosen to get the 2D spectrum, and then by the means of the Taylor series expansion of 2D spectrum phase along range direction and numerical approximation, an extended bistatic SAR imaging algorithm based on Chirp-Z transform (ECZA) is proposed, which is widely suitable for the flight configuration that the transmitter and receiver follow the parallel path with equal velocity. The imaging quality is compared with the traditional Chirp-Z algorithm (CZA), and the simulation results verify the 2D imaging ability of the proposed method.