约束同时扰动随机逼近的鲁棒自适应波束形成

Robust Adaptive Beamforming Based on Constrained Simultaneous Perturbation Stochastic Approximation

为有效克服导向矢量失配误差对自适应波束形成器的影响,提出了一种基于约束同时扰动随机逼近算法的鲁棒自适应波束形成算法。该算法对波束形成器的幅度响应进行约束,运用约束同时扰动随机逼近算法对权矢量进行优化,算法只需要对阵列输出功率进行测量,无需知道接收数据协方差矩阵,可适用于低成本的单通道接收系统。此外,该算法能很好地处理非凸的优化问题,无需将其转化为凸优化问题,能够自由控制鲁棒响应区的波束宽度和纹波水平,理论上可适用于任意阵型。仿真结果验证了算法的正确性和有效性。

To overcome effectively the influence of steering vector mismatch on the performance of adaptive beamformer, a robust adaptive beamformer based on the constrained simultaneous perturbation stochastic approximation（SPSA） algorithm is proposed.The magnitude response constraints are used in the proposed method, and the constrained SPSA algorithm is used to solve the optimal weight vector.The proposed approach just need the measurements of the output power of the array antenna, and does not need the received signal covariance matrix, so it is very suitable for the low cost single-channel receiver.Moreover, the proposed approach is able to solve the non-convex optimization problem, and does not convert it to a convex optimization problem.It is also able to flexibly control the robust response region beamwidth and response ripple for antenna arrays with arbitrary geometry.The simulation results verify the correctness and effectiveness of the proposed approach.