利用麦克风阵列的管道主动噪声控制方法

Duct active noise control method using microphone array

中文关键词  主动噪声控制  声反馈  管道系统  FxLMS  麦克风阵列

英文关键词  active noise control  acoustic feedback  duct system  FxLMS  microphone array

中文摘要

      空调通风管道在运行时, 内部出现的低频噪声很难通过包裹消音材料等被动式降噪方法消除. 而在部署主动噪声控制时, 会出现声反馈现象, 影响降噪性能甚至造成控制系统的响应发散. 针对这种声反馈现象, 本文在分析其产生原因的基础上, 将麦克风阵列作为前馈, 对Duvall-Frost结构的线性约束最小方差波束成形算法加入预调向,提出了利用麦克风阵列的管道主动噪声控制方法, 实现单方向拾取来自管道上游的噪声信号, 避免声反馈带来的影响. 并利用滤波器x最小均方误差(FxLMS) 算法作为自适应控制算法, 针对4种典型低频噪声, 在真实管道环境下进行主动降噪实验. 实验结果表明, 相比不使用麦克风阵列的情况, 本文提出的主动噪声控制方法能达到明显的降噪性能, 且在稳定性方面取得较好结果.

英文摘要

      During the operation of air conditioning ventilation ducts, the low-frequency noise generated internally is difficult to be eliminated through passive noise reduction methods such as wrapping silencing materials. When deploying active noise control, acoustic feedback may occur, affecting noise reduction performance and even causing control system divergence. In response to this acoustic feedback phenomenon, based on the analysis of the causes, this paper takes the microphone array as the feedforward, adds the linear constrained minimum variance beamforming algorithm of Duvall Frost structure with pre-tuning, and proposes an active noise control method using the Microphone array in the duct, which can pick up the noise signal from the upstream of the duct in a single direction to avoid the impact of acoustic feedback. The filter x minimum mean square error (FxLMS) algorithm is used as the adaptive control algorithm, and active noise control experiments are carried out in the duct environment for four typical low-frequency noises. The results show that compared to the situation without using a microphone array, the design in this paper can achieve good noise reduction performance and achieve good results in terms of stability.