载波跟踪环路统计特性分析的欺骗检测方法

Spoofing detection method of carrier tracking loop statistical property analysis

针对现阶段大部分卫星导航接收机跟踪阶段的欺骗检测方法只能检测单欺骗源发射的欺骗信号的问题,提出一种基于载波跟踪环路统计特性分析的欺骗检测方法。首先分析了跟踪阶段已有欺骗检测方法的不足;其次,建立了接收机正常接收信号模型和欺骗信号入侵后接收信号模型,对真实信号与欺骗信号的复合信号的统计规律进行了分析。理论分析表明,当欺骗信号与真实信号存在频差时,检测算法能够通过I路信号的幅度变化检测出欺骗信号。仿真结果表明,在接收机能接收到的正常载噪比范围内(28 dB·Hz^50 dB·Hz),在2%的虚警概率下能够达到100%的检测概率。算法能够检测多欺骗源发射的欺骗信号,且检测性能比已有方法得到了提升(在载噪比相同的情况下,检测性能提升约1 dB;在干信比相同的情况下,检测性能提升约4 dB)。

Since most of the spoofing detection methods working in the satellite navigation receiver tracking phase can only detect one spoofing signal transmitted from single source, a novel spoofing detection method based on the statistical property analysis of carrier tracking loop was proposed. Firstly, the shortcomings of the existing spoofing detection methods were analyzed. Secondly, the received signal model under the spoofing attack environment was established and the statistical character of the complex signal which composites the real and spoofing signals was analyzed. Theoretical analysis shows that when the frequencies of the spoof signal and real signal are different, the novel algorithm can detect the spoofing signal since the I-branch signal＇s amplitude is not stable. The simulation results show that the proposed method can achieve 100% detection probability under 2% false alarm probability when the carrier-to-noise ratio of the received signal in the normal range （28 dBHz to 50 dBHz）. By using the proposed algorithm, the spoofing signals transmitted from different sources can be detected, and the performance is greatly improved compared with the existing methods （about 1 dB under the same carrier-to-noise ratio, and about 4 dB under the same interference-to-signal ratio）.