基于功率估计的高动态GNSS抗干扰零陷展宽算法

Null widening algorithm for GNSS using a novel signal power estimation in high speed environment

全球卫星导航系统(GNSS)接收机在高速运动状态下时,干扰来向的快速变化会导致阵列抗干扰算法性能下降,为此,提出一种基于功率估计的抗干扰零陷展宽算法。根据特征值将采样协方差矩阵划分为信号子空间与噪声子空间,通过子空间投影确立信号导向矢量与功率的线性关系;利用线性关系估计干扰功率,并根据零陷展宽需求重新设定干扰区域内的信号功率;最后,以干扰区域内功率的估计值为基础重构干扰加噪声协方差矩阵,求解阵列权矢量。仿真表明,相比其他零陷展宽算法,所提算法在相同展宽下具有更深的零陷,阵列输出信干噪比也有所提升。

When Global Navigation Satellite System(GNSS)receivers move in high dynamic environment,the Directions Of Arrival(DOAs)corresponding to interferences may change rapidly,which will reduce the performance of anti-jamming algorithm.A novel null widening algorithm based on signal power estimation is proposed.Firstly,according to the eigenvalues,the Sampling Covariance Matrix(SCM)is divided into signal subspace and noise subspace,and a set of linear equations is established based the signal subspace projection.Then,the signal powers around interferences are reset according to the required null width based on the linear equations.Finally,the Interference-plus-Noise Covariance(INC)matrix can be reconstructed with the reset signal power,based on which the weight vector is solved.Simulation shows that the proposed algorithm has a deeper null than other algorithms when the null width keeps the same,and the Signal to Interference Noise Ratio(SINR)of array output is also improved.