New development of ECS algorithm for SAR imaging processing

Traditional extended chirp scaling (ECS) algorithm, after RCMC in the range signal/Doppler domain, can not equalize the FM rates of targets in the same range gate. In this paper, a novel approach for high squint missile-borne SAR data processing using a modified extended chirp scaling algorithm is proposed. A non-linear chirp perturbation function (CPF) is presented and can be applied to each range gate to equalize the targets FM rates before azimuth compression, which can accommodate azimuth compression and improve precision of algorithm. Comparison between this development named modified ECS with traditional ECS algorithm is implemented and several simulations of point targets demonstrate the validity.