Research On Methodology Of 3D Sound Source Localization And Identification With Planar Array Based On Beamforming Theoty

The beamforming with planar array is the basic method of far field source identification and localization, the domestic and international famous acoustic technology companies have developed corresponding acoustical holography equipment, which are quite expensive. But this kind of holography equipment can only identify the position of planar source (2D source), they can’t identify the depth of three dimensional source, namely the beamforming with planar array based acoustical holography can not accurately identified the 3D coordinates of sources, particularly, they can’t recognize the sound source located in front of the planar array or behind. Considering their technical limitations, this thesis proposed a methodology which makes use of the maximum value of the responses of 3D sound field and planar array combined with beamforming theory to identify the position of three-dimensional sources.First of all,this thesis reviewed the research references and documents, and then derived the mathematical model and algorithm, based on beamforming principle,of the sound source identification and localization with a line and two dimensional microphone array, and analyzed the limitations of traditional beamforming method in theory. The third chapter of the thesis presented a methodology and derived the mathematical model and algorithm, and the comparison of simulated a single point source with background noise and the theoretical value was made, the accuracy was discussed. On the other hand, the identification of 3D sound sources was analysed quantitatively, by varing X and Y locations of the two point sources and their source frequencies. The fourth chapter of this thesis presented the experimental verification. The experiment selected a small speaker as the targeted source, B&K’s slice wheel array of 60 channels was used to measure the acoustic pressures in anechoic chamber in order to verify the effectiveness and accuracy of the proposed methodology. The experimental results show that the beamforming based the maximum value of the responses of 3D sound field with slice wheel array could identify the sound source location by indicating its three coordinates.Finally research results in this paper have been mainly summarized, the futher issues of beamforming based on the maximum value of the responses of 3D sound field with slice wheel array were stated.