Effects of RFI on UWB-SAR using LFM waveforms

The dual requirement of ultra-wide band synthetic aperture radar (UWB-SAR) for high range resolution and low frequency penetration proposes the problem of radio frequency interference (RFI) suppression. Although careful design of the receiver hardware can reduce this difficulty, a great amount of RFI will still distort the actual target returns. The effects of RFI on both of the design of hardware and the task of signal processing are studied. We focus our analysis on the basic pulse compression in linear frequency modulated (LFM) UWB-SAR. The output of a typical sinusoidal RFI after pulse compression is derived and proved to be closely related to the frequency of the RFI. Computer simulations successfully verify our conclusions.