An Efficient Method for Ground Maneuvering Target Refocusing Based on DPT-MFP

Ground maneuvering targets may be smeared in a synthetic aperture radar (SAR) image due to the Doppler ambiguity, high-order range migration (RM) and Doppler frequency migration (DFM) caused by unknown motion parameters. To address these problems, an efficient method based on discrete polynomial-phase transform (DPT) and matched filtering process (MFP) is developed to refocus the ground maneuvering targets in this paper. Firstly, the DPT is applied to eliminate the quadratic RM, cubic RM and quadratic DFM simultaneously. Then, the matched filtering functions are constructed to remove the residual linear RM and linear DFM. At last, the target energy is well focused by performing the azimuth fast Fourier transform (FFT). The proposed algorithm has high computational efficiency and superior performance of target detection and motion parameters estimation under high signal to noise (SNR) environment. The numerical results prove the effectiveness of the proposed method.