基于脉冲声分离的刚性球散射声控制  

Active noise control for the scattered sound of rigid sphere based on the impulsive signal separation method

作　　者：王冉 王晓琳[1] 杨军[1,2] WANG Ran;WANG Xiaolin;YANG Jun(Institute of Acoustics,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院声学研究所,北京100190 [2]中国科学院大学,北京100049

出　　处：《应用声学》2021年第6期897-903,共7页Journal of Applied Acoustics

摘　　要：提出了一种基于脉冲声的三维空间中刚性球散射声分离方法,并利用前馈、固定系数控制方式对分离出的散射声进行有源控制,抑制散射声强度,实现了刚性球散射体在观测点处“声学不可见”。该方法利用脉冲信号作为初级噪声,通过有无刚性球时传声器采集脉冲信号的差值确定散射声大小,实现散射声与声源直达声的分离。对分离出的散射声进行多通道有源控制以验证该文所提分离方法及控制系统的有效性。实验结果表明,7001000 Hz范围内,有源控制开启后,双通道散射声的平均降噪量大于5 dB,多通道散射声的平均降噪量大于8 dB,且误差传声器处采集的残余声场与无刚性球时采集的初级声场信号波形基本一致,实现了刚性球散射体在误差传声器处“声学不可见”。此外,参考传声器布放位置的选取问题也在该文做了详细讨论。A method for the rigid sphere scattered sound field separation in three-dimensional space based on the impulsive signal is proposed.And the scattered sound pressure is further used as error signal in the active noise control(ANC)system where feedforward and fixed-coefficient filter is adopted.Therefore,the scattered sound pressure is suppressed and it realizes the rigid sphere invisible at the error point.In this work,the impulsive signal is adopted as the primary source,and the scattered sound pressure is acquired via the sound pressure difference of the microphone with and without the sphere existence.Then the active noise control is implemented to suppress the scattered sound pressure to verify the effectiveness of the proposed scattered sound field separation method and the ANC system.The experimental results show that in the range of 700–1000 Hz,the average noise reduction at the error point is more than 5 dB and 8 dB with two-channel and multi-channel ANC system.And after the active noise control is on,the residual sound pressure and the primary sound pressure at the error point are basically the same which confirms the scattered sound pressure is suppressed and the rigid sphere is invisible at the error point.In addition,the location of the reference microphone is also discussed in the paper.

关 键 词：有源噪声控制 前馈控制 散射声场 

分 类 号：TB53[理学—物理]