有距离辨识度的传声器阵列波束优化算法研究*

小尺度线性传声器阵列在便携式通信设备中具有潜在应用前景,其波束优化算法大多关注于抑制来自与声源不同方向的噪声,而不能有效地抑制与声源同方向的噪声。本文通过对几种典型波束优化策略进行改进,增加线性约束条件,使得阵列兼具方向和距离辨识度。论文对比了几种优化方法的波束性能,同时讨论了约束条件对波束旁瓣的影响,并提出了鲁棒性的优化方案。仿真结果显示,合理的优化策略和线性约束条件可以使阵列波束获得很好的聚焦性能。

microphone array beamforming algorithms with distance discrimination

Small size linear microphone array has potential applications in mobile communication devices. Conventional beamforming optimization algorithms usually emphasize only on distinguishing signals from different directions, while they cannot attenuate noise from the direction of the expected signal. This paper investigates the feasibility of beamforming for both angle and distance discrimination by introducing a set of linear constraints to several typical optimization strategies. The performances of different methods are compared, and the influence of the constraint values on the sidelobes is discussed. Furthermore, the robust optimization method and the broadband optimization method are proposed. Simulation results illustrate that the beamformer can get good focusing performance by using suitable optimization strategy and constraint conditions.