Spectrum spread and compression shift-frequency jamming suppression by combining generalized S transform and threshold segmentation

According to the time-frequency distribution difference between SSC (spectrum spread and compression) shift-frequency jamming and echo, a jamming suppression method based on generalized S transform and Tsallis cross entropy threshold segmentation was proposed. The jamming principle of SSC shift-frequency jamming was analyzed and the jamming signal model after dechirp processing was constructed. And the generalized S transform, which is of good time-frequency concentration performance, was utilized to acquire the time-frequency image of received signals after dechirp processing. Based on the related gray-scale image of time-frequency image, the minimum Tsallis cross entropy was utilized to obtain the optimal segmentation threshold and the time-frequency filter was constructed according to the segmentation threshold to suppress jamming. The simulation results show that the proposed method is of good jamming suppression performance to the false targets produced by SSC shift-frequency jamming and the jamming suppression ratio can reach more than 30 dB.