一种应对非平稳频率失调的窄带主动噪声控制系统

在窄带主动噪声控制(Active noise control, ANC)系统中, 参考信号频率失调(Frequency mismatch, FM)和噪声信号非平稳将会使系统性能下降, 甚至失效. 本文提出一种基于动量最小均方的改进FM补偿算法, 通过在代价函数中引入加权累加的平方误差, 提升系统的追踪和收敛能力. 并分别与基于滤波-X 最小均方(Filtered -X least mean square, FXLMS)、滤波-X 递归最小二乘(Filtered -X recursive least square, FXRLS)和变步长滤波-X最小均方(Variable step-size filtered -X least mean square, VSS-FXLMS)算法的主控制系统结合, 共同完成系统综合性能的提高. 大量仿真分析表明, 新的FM补偿算法在非平稳的FM和离散傅里叶系数翻转的条件下仍能保持较高的追踪能力和合理的残余误差.

A New Narrowband ANC System against Nonstationary Frequency Mismatch

A frequency mismatch (FM) compensation method is proposed for the narrowband active noise control (ANC) system to solve the problem of large nonstationary FM. Inspired by the momentum least mean square (LMS) theory, a new recursion algorithm for the updating of frequency compensation sequence is derived by incorporating a weighted accumulated square error into the cost function, and applied to the conventional filtered -X least mean square (FXLMS), filtered -X recursive least square (FXRLS), and variable step-size filtered -X LMS (VSS-FXLMS) algorithms, respectively. In both stationary and nonstationary environments, extensive simulations show that the proposed FM compensation method combined with the VSS-FXLMS based main controller possesses excellent tracking ability and is fast convergent.