基于空间响应偏差约束的稳健宽带波束形成

摘要

针对宽带自适应波束形成中期望信号导向矢量失配的问题,提出了一种基于空间响应偏差(SRV)约束的稳健宽带波束形成算法.该算法在空时二维处理宽带信号模型基础上,通过增加SRV约束改善阵列响应的频率不变性能,同时结合导向矢量误差的不确定集约束和误差矩阵范数约束增强算法的稳健性.该类稳健宽带波束形成器的权值求解问题可以转化为矩阵束的广义特征值分解问题,推导了权矢量的近似闭式解.算法分析和仿真结果表明,与现有的稳健宽带波束形成算法相比,该方法在改善阵列响应的频率不变特性的同时,提高了阵列输出信干噪比(SINR)性能.%To solve the problem of signals' mismatch between the actual steering vector and the presumed steering vector in broadband adaptive beamforming, a novel robust algorithm for robust broadband beamforing based on the space-time adaptive processing model is proposed by employing the spatial response variation (SRV) constraints.The frequency invariant beampattern design is provided by applying the SRV constraint in the optimization formulations.Moreover, the steering vector uncertainty set constraint and error matrix norm constraint are combined to improve the robustness of the broadband adaptive beamformer.The robust broadband beamformer design problem can be converted to the form of the minimum generalized eigenvalue of a matrix pencil, and the approximate closed-form solution to the weight vector is derived.The extensive simulation results and the complexity analysis show that the proposed algorithm can achieve the frequency invariant beampattern and improve the output signal to interference plus noise ratio (SINR) as compared with the existing robust broadband beamforming algorithms.