基于正则化约束最小二乘的稳健频率不变波束形成器设计方法

Robust FIB Design Using Regularized Constrained Least Squares

频率不变波束形成器(Frequency invariant beamformer,FIB)在无畸变宽带声信号采集等方面具有重要应用。经典的FIB设计方法通常是在理想的模型条件下提出的,当存在由麦克风的幅度和相位响应不一致性所引起的阵列通道失配误差时,其性能会变差,无法满足实际的设计要求。本文提出了一种基于正则化约束最小二乘的稳健FIB设计方法,有效克服了麦克风阵列通道失配误差对FIB设计性能的影响。该方法适用于任意结构的阵列,并且具有闭式解,无需迭代步骤,计算复杂度较低。仿真实例证明了所提方法的有效性和理论分析的正确性。

The frequency invariant beamformer （FIB） has important applications in distortionless acoustic signal acquisition. Conventional FIB design approaches are usually proposed with ideal microphone array models. Since there is no gain and phase mismatch in microphone array characteristic, the performance of conventional FIBs degrade in practical applications. There-fore, a robust FIB design approach based on regularized constrained least squares is presented. It can work well in the presence of microphone mismatches. The proposed approach is applica-ble to arbitrary array geometries, and it has a closed-form solution, thus avoiding iterative computation and leading to a lower computational complexity in design. Several design exampies are presented to verify the effectiveness of the proposed approach and the correctness ot the theoretical analysis.