The Effect of Notch Filter on RFI Suppression

Wenge CHANG, Jianyang LI, Xiangyang LI

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DOI: 10.4236/wsn.2009.13026                

Abstract

Radio Frequency Interference (RFI) suppression is an important technique in the ultra-wideband synthetic aperture radar (UWB SAR). In this paper, we mainly analyze the performance of a notch filter for RFI sup-pression. The theoretical output from notch filter is presented based on RFI signal’s narrowband property. The research conclusion shows that the notch filter has significant effect on sidelobes of the system response, which might be considered to be false targets, however it has little effect on the resolution of the system re-sponse. The theoretical result is verified by simulation and experimental data processing both in one dimen-sion (range dimension) and in two dimensions (range and azimuth dimension).

Keywords

RFI Supression, Matched Filter, Notch Filter, SAR

Conflicts of Interest

The authors declare no conflicts of interest.

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