Research On The Far Field Source Target Localization Based On Microphone Array Technology

With the development of signal processing technology,the sound source localization based on microphone array has become a hot research field in this field.It has a wide application prospect and important application value in military affairs,traffic,intelligent robots and so on.My paper designs a set of signal acquisition experiment platform based on microphone array,the hardware platform consists of three parts:microphone array,NI-9234 data acquisition card and computer.The sound signal from the sound source is converted into a voltage signal by a microphone,the data acquisition card converts the collected analog signals into digital signals and transmits them to the computer through the network port for research and processing.Based on the signal acquisition platform,the sound source localization technology based on the microphone array is deeply studied.Firstly,the traditional method of determining the position of the sound source using the microphone array is compared and analyzed,and the localization method of the sound source based on the time delay estimation is determined.Secondly,filtering,noise reduction,windowing and endpoint detection of the collected sound signals are carried out,which can meet the requirement of time delay estimation algorithm.Then the method of time delay estimation is systematically studied,by analyzing and comparing several delay estimation algorithms and weighting functions,it is found that the peak of PHAT-weighted generalized cross-correlation time-delay estimation algorithm is more obvious than other common algorithms,and the anti-noise ability is stronger,and the PHAT weighting function is improved to make it more suitable for the external environment and single sound source studied in this paper.Finally,the time difference location algorithm is studied,and the time difference localization in 2D plane and 3D space is analyzed and simulated.On the basis of theoretical research,a software system for experiment verification of sound source localization is developed and designed,and the simulation and the actual test were carried out.The simulation and measured results were compared.The results show that the proposed method can locate the far-field sound source target and achieve the desired positioning accuracy,and the algorithm is simple and the computation is small.It is found that the accuracy of localization can be improved by parabola fitting,interpolation sampling rate,temperature compensation method and increasing the number of microphone array elements.On this basis,the errors of sound source localization system are analyzed.