基于主辅通道联合处理的无源雷达同频干扰抑制方法研究

基于民用通信信号的无源雷达由于其辐射源分布密集，主通道与参考通道容易同时受同频辐射源干扰，严重影响检测效果。针对上述问题，该文提出了一种加入同频干扰抑制的信号处理流程。改进流程首先对所有通道接收信号联合处理，使用多通道盲反卷积算法估计各个辐射源直达波，再利用各通道主辐射源信号能量占比差异识别主辐射源直达波作为参考信号，然后对主通道中各辐射源杂波信号进行对消，最后用主辐射源直达波与对消剩余信号进行互模糊运算，完成目标检测。改进流程可以在不改变现有系统硬件条件的情况下有效抑制同频干扰，提升对消比，降低互模糊函数底噪，减少漏警。仿真分析与实测数据验证说明了该方法的正确性和有效性。 

Research on Co-channel Interference Suppression Method for Passive Radar Based on the Jiont Processing of Primary and Reference Channels

The illuminators of passive radar based civil communication signals are densely distributed. As a result, the co-channel illuminator always interferes with the primary and reference channels, resulting in poor detection performance. To solve the aforementioned problem, an improved signal processing flow with co-channel interference suppression is proposed in this paper. First, signals from all channels were processed jointly. The direct-path wave of each illuminator was estimated using the multi-channel blind deconvolution algorithm. Then, the direct-path wave of the primary illuminator was identified as the reference signal by applying the difference in the proportion of the primary illuminator signal energy among channels. Then, the clutter of each illuminator in the primary channel was suppressed by utilizing each of the above estimated signals. Finally, the residual signal, after cancellation, was used to compute the cross-ambiguity functions with the identified direct-path wave of the primary illuminator for target detection. The improved flow can promote the cancellation ratio and reduce the bottom noise of the cross-ambiguity function and missed alarm. Co-channel interference can be effectively suppressed using the improved processing flow without changing the radar system’s hardware. The validity of the proposed method were confirmed by the results of the simulation and experiment.