Research And Realization Of Sound Source Localization Algorithm Based On Microphone Arrays

This thesis is attached to the project of "Research of track security detection principle based on wheel-rail noise" which was supported by the National Natural Science Fund. The project is intended to study the noise produced by the interaction between train wheel and rail in order to extract the information of wheel-rail's quality condition, and finally to realize the state detection and fault diagnosis of wheel/rail system, which will improve tand optimize themethod of the track detection in China.This thesis "Research and Realization of Sound Source Localization Algorithm Based on Microphone Arrays" is to apply in determining the localization of wheel-rail noise source. The localization accuracy is directly related to effect of useful signal extracting. Under this background, the following work was accomplished.Firstly, a high-performance experimental platform for data acquisition was designed which can be applied to collect and analyze complex audio signal with the corresponding audio signal sensors.Secondly, according to the specific requirements of the project characteristics, the voice of the near field and the far field model to determine the type and location of sound field, ascertain the range of this paper; introduced three kinds of typical sound source localization algorithm,according to the choice of suitable for this algorithm in-depth features.Thirdly. The location method based on controllable beam is studied, and simulation analysis is done to optimize the algorithm ; And the reduced space search algorithm is introduced into the fault diagnosis and location of wheel rail noise, The experimental results show that the accuracy of the improved algorithm is improved by 36%, and the algorithm consumes only 28% of the time.Meanwhile, the algorithm has good anti noise performance.Fourthly, the method of time delay based localization is studied. Simulation analysis is carried out and a set of practical positioning system is established to carry out experiments, and means of time delay localization method, the coordinate function of equilateral triangle array to 3D source coordinates is realized. According to the situation of this project, it is found that the maximum error value is within the allowable range of error, and the scheme is feasible.