基于干扰矩阵重构的稳健自适应波束形成算法

Robust Adaptive Beam-Forming Algorithm Based on Interference Covariance Matrix Reconstruction

针对较高信噪比下自适应波束形成性能退化问题,提出了一种基于干扰噪声协方差矩阵重构的新型稳健自适应波束形成算法。利用空间谱估计方法重构出不含期望信号的干扰噪声协方差矩阵,保证了高信噪比时波束形成器的输出增益;并基于信号子空间与干扰子空间的正交性建立了期望信号导向矢量估计的约束条件,以求解出近似最优的权值矢量。理论分析和仿真结果表明,当存在随机指向误差和局部散射时,该算法在较大输入信噪比范围内的性能仍接近最优,较现有算法稳健性更强。

A robust adaptive beam-forming algorithm is proposed based on interference covariance matrix to deal with the performance degradation of beam forming in high Signal-to-Noise Ratios （SNRs）. To ensure the output gain of beam former in high SNRs, the real covariance matrix is reconstructed using spatial spectrum estimator. In order to estimate the optimal weight vector, the constraint expression of signal steering vector estimation is formulated based on the orthogonality of signal subspace and interference subspace. Theoretical analysis and simulation results demonstrate that, in the presence of random signal look direction mismatch and local scattering, the algorithm is always close to the optimal value in a large range of SNRs and more robust than the existing ones.