Nonstationary Interference Excision for Noise Radar Systems using Time- Frequency based Methods.

摘要

The problem addressed in this memorandum is nonstationary interference suppression in noise radar systems. Towards this aim, linear time- frequency (TF) transforms, short time Fourier transform (STFT) and local polynomial Fourier transform (LPFT) are used as a means of signal representation. The noise radar return signal is a wideband random signal occupying the whole TF plane, while the interference signal is well concentrated in the TF plane. This implies that the filtering of the received signal can be performed by using a binary mask to excise only a portion of the TF plane corrupted by the interference. Simulations carried out on the radar return signal corrupted by an extremely strong nonstationary interferences, covering the same time and frequency ranges. Results confirm the effectiveness of the proposed method.