The Research On Acoustic Source Localization Based On Microphone Arrays

Acoustic source localization with microphone arrays refers to that the location of acoustic source is determined by the signal imformation received from several microphones arrayed with a certain geometric structure.Acoustic source localization techniques have a variety of important uses in videoconferencing,targets'direction finding,speech recognition,sound detection and speech enhancement.An array of microphones has a number of advantages over a single-microphone system.It may be electronically aimed to provide a high-quality signal from desired source localization and does not require physical movement to alter these microphones' direction of reception. It has capabilities that a single microphone does not, particularly noise processing and acoustic source localization. The work presented in this thesis is based on one state-of-art framework used in acoustic source localization with microphone arrays, time delay estimation based on acoustic source localization.First, the algorithms on time delay estimation are researched., especially the theory of generalized cross-correlation method, what is more,the traditional method of generalized cross-correlation was developed ,sepecifically usefulness to background noise and room reverberation alimination.,and the results of computer simulation shows that the method developed outperforms the traditional method. The LMS method is also discussed from two aspects:the time-domain and the frequency-domain, then other two method——localization by initial envelope of the signal receivd and localization by Gourth-order cumulants were also be researched. The second key technique on time delay estimation based acoustic source localization is the structure of microphone arrays. The sound source localization method based on four-element planar crisscross array was investigated and the localization equations are derived followed by the performance analysis.Then in order to improve the shortcomings of four-element array ,a kind of five-element array was discussed,as while as a search method.The simulation results are helpful for the acoustic array system design in the practical applications. In the end, a pratical system for microphone array speaker localization,which can suppress noise and reverberation,are presented...