Countermeasure for Interrupted-sampling Repeater Jamming based on Fractional Fourier Transformation

Abstract

Today, the interrupted-sampling repeater jamming (ISRJ) has posed a serious threat to LFM radars. In this paper, a countermeasure to suppressing ISRJ based on fractional Fourier transformation (FrFT) is presented. The echo signals, mixed with ISRJ, will be processed in FrFT of specific order, and then a narrow band filter based on parameters of FrFT is designed to extract the target signals and suppress interference signal, so as to realize the target detection. The three kinds of models of ISRJ (ISDRJ, ISRRJ, ISCRJ) are introduced; the anti-jamming principles are analyzed and simulated. The simulation results show that, the algorithm has low complexity and takes short operation time, and it is effective in low SNR or high JSR condition.

Countering self-protection interrupted sampling repeater jammer against chirp radar

“…But, the jamming suppression performance depends on the accuracy of jamming parameters 15, estimation. In [26], the radar return filtering is achieved by transforming it into the fractional domain and designing a narrow BPF to suppress jamming signal. The center of the BPF can be set according to the true target peak position in the fractional domain.…”