RFI suppression algorithm based on median filter for SAR data

This paper proposes a novel method based on median filter for radio frequency interference (RFI) suppression applied to synthetic aperture radar (SAR). The RFI has higher power than the useful echo signal and has narrow property in range frequency domain. A threshold called max-mean-ratio (MMR) is proposed to detect the RFI existence. If the RFI exists, then the echo signal is processed with a median filter. The method is verified with the linear frequency modulation (LFM) and point target simulation. In the end, the method is applied to RadarSat-1 data to demonstrate the performance.