Research Of Uniform Accelerated Moving Sound Source Localization And Sound Field Visualization Based On Microphone Array

The sound radiion and visualization of moving sound source has always been ahotspot of experts and scholars.Understanding the motion state of moving sound sourceis the precondition of solving moving sound field. The visualization technology basedon microphone arrays and beamforming theory makes it clear and easier to identify thelocation and intensity of moving sound source.Because the forms of microphone arrayshave a great effect on the directivity of sound field,therefore, the common forms ofmicrophone arrays need to be optimized to obtain an ideal array form which performs abetter directivity of sound field.It is the ultimate goal of this paper to use the optimizedmicrophone array designing a real-time sound field visualization system. The mainwork and innovations of this paper are as follows:(1) Based on the basic theories of sound radiation, the model of moving sound fieldis established.Then the calculation method of uniform acceleration is alsoanalyzed.After discussing the main influence of uniform acceleration motion, theAcoustic vector is defined and numerical analyzed.Then the calculation method ofsound field with uniform accelerator is obtained.(2) Delay and sum beamforming algorithm, MVDR algorithm and MUSICalgorithm were discussed to locate the sound source.And simulations were carried outwith these methods.Advantanges and defects of the algorithms were studied and theireffectiveness in sound source was also learned.(3) Compared the array performance between regular form arrays and irregulararrays by using beamforming algorithm, when the array aperture and the number ofmicrophones were the same. Then, optimized the directivity of microphone array bychanging the array form.(4) Based on the optimized arrays, the source location and visualization systemwas developed, it could realize real-time and off line analysis.The system was made upof two parts. One of which was the hardware system. The system composed of powermodule, microphone module, data acquisition module etc. The other system wassoftware system; the source location system was programmed based on Labview, whichcould realize harmonic human.machine interaction. (5) The experiments were carried out by using the system to test the performanceof the array system in anechoic chamber with moving sound source; then modified themoving car out of the anechoic chamber with the source location and visualizationsystem.The experiment data showed that the precision of the system is good for soundsource location and sound field visualization.