Anti Repeater Jamming Method Based on Phase Noise Joint Time-Frequency Analysis

The jammer utilizes a digital radio frequency memory (DRFM) system to generate a large number of jamming signals highly correlated with the target echo, thereby reducing the performance of radar target detection and tracking. This article establishes a model for the influence of phase noise on the interference signal of a full duplex jammer (transmitting and receiving simultaneously) forwarding system, and analyzes the differences between radar target echo and jamming signal. Perform de-chirping processing on radar received echoes and time-frequency analysis, use bandpass filtering to extract the Allan variance corresponding to jamming and target echoes, as well as the single sideband noise carrier power ratio, to identify the frequency corresponding to target echoes. Finally, the target echo signal is reconstructed after time-frequency domain filtering. The simulation experimental results show that this algorithm can accurately identify real targets and effectively suppress DRFM repeater jamming.