Interrupted Sampling Repeater Jamming Suppression Method Based on Intra-pulse LFM-Costas Frequency Coding and Intrinsic Integration Sequence

An interrupted sampling repeater jamming (ISRJ) suppression method based on intra-pulse Costas frequency coding linear frequency modulation (LFM) and intrinsic integration sequence (IIS) is proposed to minimize the exclusion of sub-pulses and preserve the target energy. Firstly, the intra-pulse LFM-Costas waveform is encoded. Secondly, after frequency domain filtering and segmented pulse compression, the sub-pulses containing ISRJ are identified by K-means method. Thirdly, the precise temporal position of ISRJ within the sub-pulses is determined by extracting the IIS and calculating the peak amplitude curve, and then ISRJ can be suppressed. Finally, intra-pulse accumulation is performed on all sub-pulses. Simulation results validate the effectiveness of the proposed method.