Study On Random Microphone Array Structure Generating Method And Experiment For Locating Moving Sound Source

The localization of moving sound source is the research hot-spot and difficult-spot inthe noise and vibration control filed. In order to overcome the limitation of regularmicrophone array when it is used to locate moving sound source, this paper studies themicrophone array localization method of moving sound source and the influence ofarray structure on localization accuracy. Through theoretical analysis and simulationcalculation, an efficient generating method of random microphone array structure andits quantitative evaluation criteria of sound source localization performance areproposed. This method greatly improves the moving sound source localization accuracyof microphone array. The main work and innovations of this paper are as follows:(1) Based on the beamforming principle, the sound source localization mechanism ofthis algorithm is explored. Then the localization principles of different microphonesub-array structures are also analyzed. And sound source localization results of differentregular microphone array and their reasons are discussed in this paper.(2) On the basis of defining the influence of microphone array structure on soundsource localization accuracy, random microphone array is proposed to locate movingsound source. By researching moving sound source localization principle, the purposeof generating random microphone array structure is defined. In order to determine thebasic dots array, radii of non-equidistant coaxial circles are derived in this paper. Theanalysis of microphone array aperture provides the theoretical foundation for arraypartitioning.(3) In the polar coordinates, non-equidistant coaxial circles are adopted as basic dotsarray. The generating method of objective random microphone array structure which isused to locate moving sound source is innovatively proposed by controlling polar radiusand polar angle. The generating steps are “array partitioning—conditionfiltering—evaluation filtering”. Finally, the generating method is realized through aMatlab program.(4) By researching on the performance parameters of objective random microphone array and comparing with the performance parameters of regular microphone array, it isverified that the objective random microphone array has excellent localizationperformance of sound source from theoretical perspective.(5) Finally, the objective random array is constructed to actual microphone array,and it is used to conduct the sound source localization experiment of a moving car in theoutfield. The results of experiment show that the objective random microphone arrayhas good localization performance of moving sound source. The feasibility andeffectiveness of random microphone array structure generating method are also verified.