加载与约束结合的主瓣干扰抑制方向图保形

Reshaping pattern under mainlobe interference suppression with combinating diagonal loading and linear constraints

针对基于阻塞矩阵实现主瓣干扰抑制的波束指向偏移问题,提出了一种基于对角加载与线性约束相结合的方向图保形方法。通过深入分析阻塞矩阵预处理方法,发现预处理后波束指向偏移是由自适应波束形成算法中的协方差矩阵失配引起的,故提出利用对角加载实现波束指向的准确校正,利用线性约束实现其它干扰方向的准确置零,有效实现了预期的自适应波束形成效果。通过仿真分析不仅验证了所提方法的正确性和有效性,同时发现所提方法对加载电平的选取不敏感,也即加载电平的选取比较容易。

For the problem of beam direction offset that caused by mainlobe interferences suppression based on blocking matrix,a pattern reshaping method is proposed which is based on the combination of diagonal loading and linear constraints.By analyzing the blocking matrix preprocess,the problem of beam direction offset is caused by the covariance matrix mismatch in the adaptive beamforming algorithm.The diagonal loading method is used to correct the beam direction,and the linear constraints is used to certify the beam pattern nulling in the interference direction,so the expected adaptive beamforming is obtained.Simulation results show the effectiveness of the proposed method,and it is insensitive to the value of load level,which means it is easy to choose.