Frequency-shift Jamming Identification Methods Based on Positive and Negative Frequency Shift Pulse Compression Coherent Integration

Frequency-shift jamming is a kind of spoofing jamming for Linear Frequency Modulation (LFM) pulse radar based on digital radio frequency memory. In order to resist the frequency shifting interference, by studying the pulse compression process of frequency shifting interference signals, the conclusion that the output energy of two signals with a frequency difference is negatively correlated with the frequency difference after time domain convolution is concluded. Based on this characteristic, a method for identification of frequency shifting interference based on phase-coherent accumulation of positive and negative carrier frequency pulse pressure is proposed, which can effectively counter frequency shifting interference with conventional LFM pulse Doppler radar under the condition of self-defense interference. After pulse compression and phase-coherent accumulation with matched filters with positive and negative carrier frequencies respectively, the output results of real target and interference signal after processing have peak difference, and then frequency shift interference is identifed. Simulation results demonstrate the effectiveness of the proposed method.