阵列指向性二次型约束稳健波束形成算法

提出了一种基于阵列指向性二次型约束的优化算法,以提高最小方差无畸变响应(MVDR)波束形成对方向矢量的稳健性。通过控制阵列波束指向附近的小区域的自适应波束图与期望波束图的加权平方误差,使波束主瓣区域内的信号畸变最小,同时保持了对约束区间外的干扰信号的抑制能力。数值结果表明:在理想阵形和阵形畸变情况下,无方位失配时,利用本文算法的阵列输出信号与干扰噪声比(SINR)与新近出现的球面约束稳健Capon方法相当,而存在方位失配时,本文算法均优于后者。

Robust beamforming with quadratically constrained array directivity

To improve the robustness of the Minimum Variance Distortionless Response (MVDR) beamforming to the array steering vector,a quadratic constraint method is proposed.The weighted least squared error between the actual beam pattern and the desired beam pattern over a small region around the array steering direction is constrained.As a result,the signals coming from the directions near the steering angle will suffer the least distortion,and the interferences outside the constrained area can still be suppressed.Numerical results show that whether there are array perturbations or not,the array output Signal-to-Interference-Plus-Noise-Ratio (SINR) using our proposed method and the recently occurred spherical constraint robust Capon's beamforming (RCB-Sphere) is close to each other,but when exists look direction mismatch,our method outperforms the latter.