一种新型基于分布式FxLMS的主动噪声控制算法与空间平滑

A new variable spatial regularized FxLMS algorithm for diffusion active noise control

研究了多通道分布式主动噪声控制(Distributed Active Noise Control,ANC)系统的空间平滑问题.传统的分布式ANC算法通过本地控制器之间的通信,可以大大提高系统稳定性.但由于每组控制器和误差麦克风分布位置不同,引入的估计偏差影响系统整体降噪性能.因此,旨在开发一种新型扩散滤波最小均方算法(Diffusion Filtered-x Least Mean Squares,Diff-FxLMS),该算法平衡了空间平滑度和信息交换强度之间的矛盾,从而减少估计偏差.通过对Diff-FxLMS算法性能进行的理论分析,揭示了扩散控制机制,为ANC算法设计提供了理论依据,并在此基础上发展出一种新型的可变平滑度的Diff-FxLMS(Varible Spatial Regularized Diff-FxLMS,VSR-Diff-FxLMS)算法.仿真结果验证了新算法的性能及理论分析的可靠性.

This paper studies the multichannel diffusion active noise control(ANC)systems,where a group of controllers and error microphones are physically distributed at different locations within an extended area and could communicate with each other in a distributed manner.Since conventional diffusion ANC algorithms introduce the estimation bias via communication between local controllers and degrade the overall performance,we aim to develop a new diffusion filtered-x least mean squares algorithm(Diff-FxLMS)that incorporates knowledge of spatial smoothness and balances between communication strength and estimation bias.The proposed Diff-FxLMS algorithm adjusts adaptively a so called variable spatial regularization(VSR)parameter.A detailed mean performance analysis is carried out,which discloses the diffusion control mechanism and provides guidance for ANC algorithm design.A practical formula that updates VSR is then derived based on the theoretical analysis.Performance of the proposed VSR-Diff-FxLMS algorithm is verified by simulations.