Wideband Interference Mitigation for SAR Based on Intrinsic Chirp Component Decomposition

The wideband interferences (WBIs) seriously degrade the quality of the synthetic aperture radar (SAR) image. Since the WBI occupies a larger bandwidth, it is difficult to mitigate it. Some existing WBI mitigation methods based on transform-domain analysis or filter design suffer from model mismatch and signal loss. In order to solve this problem, a method based on instantaneous frequency (IF) estimation and intrinsic chirp component decomposition (ICCD) is proposed to suppress WBI in this paper. First, a WBI-contaminated SAR echo is represented in the time-frequency domain by using the short-time Fourier transform (STFT). Then, the IF estimation is carried out for the WBI components. Finally, the WBI is extracted by using the ICCD. The experimental results verify the effectiveness of the proposed method.