相位响应固定幅度响应约束的稳健波束形成方法

传统的幅度约束波束形成器是一个非凸问题，需将原始模型化为线性规划进行间接求解。该文针对均匀线阵提出一种相位响应固定幅度响应约束(PFMC)的稳健波束形成方法。利用权矢量逆序列对应的传递函数与阵列响应函数只差一个相位因子这一性质，将阵列响应的相位设置为固定的线性相位，仅对阵列响应的实数幅度进行约束，从而得到一个凸的代价函数，最优权矢量可以利用内点法求出。同时考虑到协方差矩阵误差，利用最坏(WC)情况性能最优原理提出PFMC-WC算法改善PFMC的性能。与传统幅度约束波束形成器相比，减少了约束个数并省掉了恢复权矢量过程，从而降低了计算量。此外，由于相位响应得到保证，该文算法相对于传统算法具有更好的性能。仿真实验验证了该文算法的有效性。

Robust Beamforming with Phase Response Fixed and Magnitude Response Constraint

The conventional magnitude constraints beamformer is a non-convex issue which is reformulated as a linear programming issue. A robust beamformer with Phase response Fixed and Magnitude response Constraint (PFMC) is proposed for Uniform Linear Array (ULA). Making use of the property that there is only a phase factor difference between the transfer function of the inverse sequence of the weight vector and the array response function, the phase response is set to be linear and the real magnitude response is constrained. Thus, a convex optimization cost function is established whose optimal solution can be found out by highly efficient interior point method. The PFMC-WC method against covariance matrix error is proposed based on Worst Case (WC) performance optimization to improve the performance of PFMC. Compared with the conventional magnitude response constraint beamformer, the proposed method reduces the number of constraints and leaves out the processing of recovering the weight vector, therefore, the calculation cost is reduced. In addition, due to the guarantee of the phase response, the proposed beamformer has better performance than the traditional magnitude constraint beamformer. Simulation results demonstrate the effectiveness of the proposed beamformer.