An improved RD algorithm of curved trajectory bistatic SAR based on Chebyshev polynomials

Abstract

According to the requirements of high resolution real time imaging of curved trajectory Bistatic Synthetic Aperture Radar (BiSAR), an improved RD algorithm is proposed in this paper. Firstly, the slant range of curved BiSAR is established by Chebyshev polynomials. Secondly, linear range cell migration (LRCM) and Doppler linear phase are compensated, and the high order approximate two-dimensional spectrum of echo signal is obtained by the method of series inversion (MSR) and Chebyshev decomposition. Finally, the focused image is obtained by matched filtering and phase compensation. By using Chebyshev polynomials to approximate slant range and spectral phase, the focus quality of BiSAR data is improved. Experimental results show that the algorithm can effectively compensate the motion error caused by three-dimensional acceleration and improve the imaging quality of the long distance edge point targets.