卫星导航信号频域抗干扰后相关峰建模及对捕获性能影响分析

卫星导航信号容易受到强干扰的影响，频域抗干扰算法是常用的抗干扰算法之一，但该方法实现有效干扰抑制的同时也会导致信号相关峰的畸变，从而造成导航信号接收性能下降.为了分析频域抗干扰算法对导航信号接收性能的影响，建立了抗干扰后信号相关峰畸变模型，并从信噪比损耗、第一旁瓣位置、峰值旁瓣比三个参数对相关峰模型进行深入分析，进一步建立了抗干扰后信号的捕获性能模型，同时对比了不同捕获策略下的捕获概率.理论分析和数值仿真结果表明，频域抗干扰后的相关峰的信噪比下降且出现了旁瓣，畸变参数与干扰参数密切相关，抗干扰滤波器会导致信号捕获性能下降.该研究成果对干扰场景下提高导航信号捕获性能提供了重要的模型支撑.

Auto-correlation function modeling of GNSS signal after FDIS method and analysis of the acquisition performance

Satellite navigation signals are susceptible to strong interference. The frequency domain interference suppression (FDIS) algorithm is one of the most useful anti-jamming algorithms. Although this method can achieve effective interference suppression, it will also cause distortion of the auto-correlation function (ACF) of satellite signal, which will degrade signal acquisition performance. In order to analyze the influence of the FDIS algorithm on the acquisition performance, the ACF model of the satellite signal after anti-jamming is established.The ACF parameters are also analyzed, such as signal-to-noise ratio loss, peak sidelobe ratio, and first sidelobe position. Additionally, the acquisition performance model after FDIS method is further established, and the acquisition probabilities under different acquisition strategies are compared. Theoretical analysis and numerical simulation results show that the signal-to-noise ratio of the ACF after FDIS method decreases, side lobes appear beside the main lobe, and the distortion parameters are closely related to the interference parameters. It also shows that the signal acquisition performance deteriorates after the FDIS method. The research results provide important model support for improving signal acquisition performance in interference scenarios.