Acoustic Positioning Technology Based On DSP Acquisition System

As an important branch of signal processing technology,array signal processing technology can complete the spatial-temporal sampling of acoustic signals,improve the gain and estimate the direction of arrival through the array of acoustic sensors.The key step of array signal processing is to use the spatial characteristics of sensor array and high-resolution algorithm to complete beamforming.Because of its high gain and 360 ° symmetry,circular array is widely used in DOA estimation in open space.In this paper,the circular array and embedded technology are used to design an acoustic positioning system based on DSP,which is used to locate the air horn car.Firstly,this paper introduces the development of array signal processing technology,beamforming technology and digital signal processor.This paper analyzes the demand of illegal whistle location,establishes the mathematical model of circular array based on microphone array,and combines the conventional beamforming algorithm(CBF),the minimum variance distortion free response(MVDR)algorithm and the multiple signal classification(MUSIC)algorithm to simulate the parameters of circular microphone array when beamforming,and demonstrates the feasibility of the scheme.Combined with the actual working environment,the system index is analyzed,and the high-performance floating-point processing unit is selected as the core of the system.The sound signal acquisition system is composed of microphone MPA201,three-stage preamplifier circuit and 8-channel high-speed analog-to-digital conversion module.The collected data is uploaded to the upper computer through UDP protocol in W5300 Ethernet transmission module.The upper computer’s acoustic positioning software completes the calculation and acoustic positioning through the data uploaded by Ethernet,and feeds back the results through the software interface.In the end of this paper,the debugging and testing results of the software and hardware system of the acoustic positioning system are given.From the estimation results,it can be seen that the acoustic positioning system functions normally and operates stably,and can complete the acoustic positioning work of the illegal vehicles.