Improved Chirp Scaling Algorithm Based on Fractional Fourier Transform and Motion Compensation

ABSTRACT

Fractional Fourier transform (FrFT) is a new tool of time-frequency analysis, and a good one to compress chirp signal and to process non-stationary motion error. Aiming at the problem of the conventional SAR imaging algorithm based on FFT and two-step motion compensation, that the effect of non-stationary error elimination is not obvious and the improvement of resolution is restricted, an improved Chirp Scaling imaging algorithm based on FrFT and motion compensation is put forward in this paper, which is expected to eliminate the influence of range motion error, so as to obtain high quality SAR images. Simulation results and imaging results of real SAR data show that the proposed algorithm can eliminate the influence of range motion error effectively (the real SAR data provided by Institute of Electronics, Chinese Academy of Sciences).

Keywords:

Fractional Fourier transform, Non-stationary motion error, Motion compensation, CS algorithm, High resolution.