Interrupted sampling repeater jamming recognition and suppression based on phase-coded signal processing

•The cross ambiguity function of ISRJ is derived to demonstrate jamming distribution characteristics visually.•An ISRJ recognition and suppression method based on phase-coded signal processing is proposed.•The proposed method does not need to estimate ISRJ parameters, and it is applicable for suppressing direct forwarding ISRJ, repeated forwarding ISRJ, and frequency shifting ISRJ. In modern electronic warfare, interrupted sampling repeater jamming (ISRJ) seriously affects radar target detection performance. It has the advantages of flexible modulation and fast response. The existing approaches mostly require accurate ISRJ parameter estimation and only apply to a specific type of ISRJ. We propose an ISRJ recognition and suppression method based on phase-coded signal processing. By analyzing the cross ambiguity function (CAF) of ISRJ, we find that ISRJ can form multiple peaks, and these peaks are uniformly distributed on the Doppler cut of the CAF. Using this characteristic, we propose an ISRJ recognition method based on Doppler compensation processing. On this basis, a Doppler filtering processing method is proposed to suppress the ISRJ. Both simulated and measured results corroborate the effectiveness of the ISRJ suppression with the developed methods.