强干扰环境下声源可视化重建方法的研究进展

Research progress of visual reconstruction of sound sources in strong interference environments

准确识别噪声源是机电产品噪声控制的关键,其中,近场声全息和波束形成是两种常用的声源可视化重建方法,分别适用于近场低频和远场高频声源重建的情况。传统的声全息和波束形成方法基于自由场假设,即适用于目标声源辐射声与干扰噪声之间的信噪比大于10 dB的情况。然而很多机电产品的噪声测试只能在工作现场进行,不满足自由场条件。为此,从声学传播方程和信号处理两个方面出发,回顾了强干扰环境下声源可视化重建方法的研究发展历程,评点了每种方法的特点和适用范围。重点介绍了强干扰环境下的近场声全息方法,包括声场分离法和逆块传递函数法。另外,还介绍了混响环境下的声源重建方法以及基于信号处理的信号噪声分离方法。最后,讨论了强干扰环境下声源重建有待解决的问题及其发展趋势。

Accurate identification of noise sources is the key to noise control of electromechanical products.Near-field acoustic holography and beamforming are two commonly used acoustic source visualization methods,which are respectively applicable to the reconstruction of near-field low-frequency acoustic source and far-field high-frequency acoustic source.The traditional near-field acoustic holography and beamforming are based on the assumption of free field,that is,they are suitable in the case where the ratio of target sound to interference noise is greater than 10 dB.However,noise testing for many electromechanical products can only be carried out in the workshop where the free field condition is not satisfied.In this paper,the development history of visual reconstruction methods of sound source in strong interference environments is reviewed from the aspects of acoustic propagation and signal processing,and the characteristics and application scope of each method are evaluated.Particularly,the techniques of near-field acoustic holography in strong interference environments,including the sound field separation technique and inverse patch transfer function method,are highlighted.In addition,the sound source reconstruction method in reverberation environment and the signal and noise separation method based on signal processing are introduced.Finally,the problems to be solved and the development trend of sound source reconstruction in strong interference environments are discussed.