基于峰值预滤波次级通道在线建模的主动噪声控制系统

传统白噪声激励在线建模主动噪声控制(ANC)系统,次级通道对激励源的响应在一定程度上会干扰控制滤波器的迭代,而且会增大系统收敛后的声场能量.针对这一问题,一种新的、用于窄带噪声抵消的在线建模ANC系统被提出:利用峰值滤波器对真实次级通道进行重构,新的传递函数能够不失真地重现待抵消噪声所在频段的次级通道频率响应,并对其它频段进行抑制.最后利用该系统对舰船辐射线谱噪声进行了主动控制计算机仿真试验.结果表明:该系统简化了次级通道的传递函数,减少了白噪声对控制滤波器的干扰,提高了系统性能,并降低了系统收敛后的声场残余能量.

AN ACTIVE NOISE CONTROL SYSTEM USING ONLINE SECONDARY PATH MODELING WITH PEAK PREFILTERING TECHNIQUE

In an active noise control(ANC) system,an online secondary path modeling method with an injected auxiliary noise is often applied.However,it disturbs the convergence of the control filter and increases the residual noise of the ANC system.To mitigate this problem,a new system for narrowband noise cancellation using the online secondary path modeling method is proposed.The main feature of this system is that a peak filter is used to reconstruct the transfer function of the secondary path.After processing,the frequency response of the new transfer function remains unchanged at the frequency band of the noise to be cancelled;whereas the other bands are attenuated deeply.Using this system to cancel ship-radiated noise,the computer simulation of the ANC is accomplished.The result shows that the reconstructed transfer function of the secondary path is simplified,and the capability of the noise cancellation is improved due to the reduced disturbance to the control filer,and the residual energy of the sound field is smaller than that of the conventional system without peak prefiltering technique when the system converges.