Side-Lobe Reduction for Radio Frequency Interference Suppression via Clipping of Strong Scatterers

In this letter, we present a normalized least mean square filter with clipping of strong scatterers to suppress radio frequency interference (RFI) in low-frequency synthetic aperture radar (SAR) systems. In this filter, the impulse responses of bright scatterers are clipped after range compression to improve the performance of narrow-band RFI estimation for adaptive line enhancer. Then, the estimated RFI is subtracted from the original echo for SAR imaging; thus, the range side-lobes of bright scatterers are reduced successfully. This method is particularly applicable to situations where there are bright scatterers in the image scene. The performance for RFI suppression is investigated by using the simulated data and the raw data as well.

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