基于互相关投影导航接收机欺骗干扰抑制方法

摘要

由于欺骗干扰模拟发送与导航卫星信号相同的C/A码，这使得卫星导航接收机极易被其误导和诱骗，从而给出错误的定位信息。考虑到导航信号和同结构欺骗干扰自身都具有强自相关性，且欺骗干扰功率稍大于真实信号，该文提出一种采用阵列天线抑制同结构欺骗干扰的盲干扰抑制方法。该方法从多天线接收数据与其自身延迟的参考数据做互相关入手，利用该互相关矩阵求解干扰的正交投影矩阵，最后将投影后信号互相关矩阵的最大特征值对应的特征矢量作为最优权。该方法处理时无需已知真实信号和干扰方向的来波方向，也无需对卫星C/A码序列进行遍历搜索从而解扩。理论分析和实验结果表明，该阵列波束能够有效抑制干扰，阵列输出SNR较高，干扰抑制后接收机捕获性能不受干扰影响。%Since spoofing send similar navigation satellites C/A code, this kind of interferences can lead to the receiver misled easily, receiver will provide a wrong location information. Considering both navigation signal and spoofing with same navigation signal structure has high self-coherence characteristic, and the power of spoofing is a little higher than authentic signal, this paper proposes a blind spoofing suppression method based on array antenna. Firstly, a cross-correlation matrix is obtained by cross-correlation processing between receive data from multiple antennas and its own delayed reference data. Secondly, the orthogonal projection matrix of interference can be got by the cross-correlation matrix. Finally, the eigenvector corresponding to the biggest eigenvalue from the projected cross-correlation matrix is taken as the optimal weight. Without having known the direction of authentic signal and interference, this method avoid despreading by searching each satellite C/A code sequence before receive. Experimental results show that the array beam can effectively suppress interference with high SNR and receiver performance has no effect by the spoofing.