一种循环谱域GPS卫星导航信号抗干扰方法

A method of interference mitigation for GPS signal in cyclic spectral domain

针对弱GPS信号受到的时频重叠复杂强干扰,采用信号抵消的思想,提出了一种在循环谱域消除干扰的方法.首先通过循环谱分析获得强干扰信号的循环频率参数;然后利用自适应频移(frequency shift, FRESH)滤波器与所得干扰信号的循环频率,得到具体的强干扰重构与抵消的频移滤波处理过程;最后采用LMS(least mean square)自适应算法对频移滤波进行实际实现,即可完成对强干扰的快速去除.通过对不同干扰场景下分离出的GPS信号跟踪捕获性能仿真,验证了所提方法的有效性.

Aiming at the complicated strong interference overlapped on the weak GPS signal in time and frequency domains,and motivated by the idea of signal cancellation,a method for mitigating the strong interference in the cyclic spectral domain is proposed.First,the cyclic frequencies(CFs)of the interference are obtained by the cyclic spectral analysis;then with the obtained CFs and the adaptive FREquency SHift(FRESH)filter,a detailed process of mitigating the strong interference by the FRESH filtering is formed;finally by implementing the FRESH filtering with the adaptive least mean square(LMS)algorithm,the strong overlapped interference can be effectively mitigated.Simulations on the acquisition and tracking of performance of the separated GPS signal after the interference mitigation under different circumstances validate the proposed method.