Research on DRFM Repeater Jamming Recognition

Digital radio frequency memory (DRFM) repeater jamming is coherent with the radar transmitting signal, thus can obtain partial pulse compression gain. The jamming can achieve effects of both deception and suppression, which makes it a big threaten to modern radar. Jamming recognition is the precondition of jamming suppression. Hence a jamming recognition method based on sliding-truncation matched filter (STMF) was proposed in this paper. With two dimensional search of time delay and window width of the matched filter, the amplitude distribution can be obtained. With this amplitude distribution, the jamming chip width and interleaving times can be estimated and then the jamming type can be recognized. The simulation results shows that when the interference to noise ratio is larger than 5dB, recognition rate better than 90% with this method.