Subaperture wiener filter construction for time-varying RFI suppression in UWB SAR

Ultra-WideBand synthetic aperture radar (UWB SAR), operating in the very high frequency/ultra-high frequency bands, has foliage and ground penetrating capability to detect targets hidden in forest or under the ground. The existing services such as television, radio and communications, referred to as radio frequency interference (RFI), degrade the quality of focused UWB SAR image. The Wiener filter has been found to have superior suppression performance and be more computationally efficient than other RFI suppression methods but its construction needs additional recorded RFI data, which increases the radar system complexity. In this paper, a subaperture Wiener filter (SWF) construction method is proposed, which does not require additional recorded RFI data and can deal with the time-varying RFI. The proposed SWF has been proved efficient by real UWB SAR data.