两级结构的卫星导航压制式和欺骗式干扰联合抑制算法

压制式干扰和欺骗式干扰是全球卫星导航系统 (Global Positioning System, GPS) 中的两种典型干扰，当二者共同存在于导航信号传输环境时，干扰抑制会变得更加困难。本文提出了一种新的两级阵列信号处理方案，由于传统的功率倒置（power inversion, PI）算法可以有效抑制压制式干扰，考虑到协方差矩阵的逆矩阵的物理意义，阵列接收的信号首先经过协方差矩阵求逆处理，然后将处理后的信号向欺骗式干扰的正交子空间投影达到抑制欺骗式干扰的目的。此方法基于GPS C/A码的周期特性和相关特性，利用CLEAN方法估计出欺骗式干扰的波达方向 (direction of arrival, DOA) 进而估计其子空间。实验结果表明新方案可以同时抑制两种干扰，且方法简单运算量小，可作为一个独立的干扰抑制模块嵌入到接收机中，并验证了方法的有效性。 

Two-step GPS interference suppression algorithm for spoofing and jamming

Spoofing and jamming are two kinds of significant interferences in Global Positioning System (GPS). When they coexist in GPS propagation environment, interference suppression becomes more difficult. In the paper, a novel two-step array processing scheme is proposed. Firstly, because conventional power inversion (PI) algorithm can reject jamming effectively, the inverse covariance matrix can be first performed on the signal received by the array to mitigate jamming, considering the nature of inverse covariance matrix. Then, spoofing is suppressed by utilizing the constructed orthogonal projection matrix of spoofing, which is constructed based on spoofing’s steering vector. In the paper, the method utilized the CLEAN method to estimate direction of arrival (DOA) of spoofing according to the period repetitive feature and correlation property of GPS C/A code. The simulation results show that the proposed scheme can reject spoofing and jamming simultaneously, and it is easily realized with small computation amount. Moreover, it can be used as an independent interference mitigation module embedded in the GPS receiver. Simulation results demonstrate the effectiveness of the proposed method.