The Research On Acoustic Source Passive Localization Technology Based On Microphone Arrays

With the development of signal processing and detection technology,the method to identify the location of the target along with noise during the movement is applied to the battlefield vehicle engine noise positioning,secutity monitoring and tracking system,intelligent robot “auditory system” and other military and civil areas.Therefore,the research on the acoustic source passive localization system has practical value and significance.This paper analyzes the research status of the existing localization algorithms,then chooses the time difference of arrival algorithm which is easy to implement as the theoretical support?In the aspect of microphone array model,this paper focuses on the planar five elements cross model,derives the positioning formula based on time delay,and analyzes the factors that affect the positioning error.In order to realize the requirement of real-time and accuracy of the localization system,we put forward the overall design scheme of FPGA combined with PC,then design butterworth low pass filter circuit,gain adjustable preamplifier circuit,A/D sampling conversion circuit,FPGA control circuit and interface circuit module to achieve synchronous acquisition and real-time transmission of five channels signal;introduces the communication protocol of the system,on the basis of this,the software function design of the acquisition command and localization algorithm is completed.On this basis,we built the test platform.The system hardware performance was carried out by consistency,which consist of amplitude and phase,to verfy the system performance;and then the twice localization experiments of different test points were carried out by using the planar four elements cross array and five elements cross array,we obtained two sets of experimental data.The experimental results show that the designed five elements cross array acoustic source passive localization system has the advantages of simple structure and good real-time,it basically meets the designed requirements.