Study On The Identification Of Vehicle Noise Source With Array Technology

Automobile has been produced for more than one hundred years. With the continuousdevelopment of the science and technology, all aspects of the car performance has beengreatly improved, But with the improvement of people’s living standard, people’srequirements for the vehicle performance are constantly improve. The vehicle noise is notonly one of the important indicators of evaluation of comfort, but also becoming an importantmeans of environmental noise. With people’s increasingly concerned about the vehicle noiseand increasingly strict of the vehicle noise limit standard, noise control has become animportant research topic in the development of the vehicle industry. The key to the noisecontrol is the identify the location of the noise source. Only identify the location of the noisesource correctly, we can analysis the mechanism of noise generation correctly, which hasfar-reaching significance to the following vehicle noise control.The research method of this paper is noise sources of spatial spectrum estimation whichbased on spatial spectral estimation using the type of uniform circular array. This paperpresents an improved MUSIC algorithm after the introduction of several traditional spatialspectral estimation algorithm. After measuring space radiation sound field information usingmicrophone arrays, we use the improved MUSIC algorithm to forecast the sound sourcedistribution of the vehicle, so that we can find out the location of the main noise source.First, this paper successively introduce the vehicle main noise source, domestic andforeign research status of array signal, the basic theory of acoustics and several kinds oftraditionalsound source localization method. This paper establishes the digital signal modelof the uniform linear array and the uniform circular array based the theory of the microphonearray characteristics. Through comparing the square array of the directional diagram, thispaper uses the uniform circular array as the research array type.this paper presents animproved MUSIC algorithm after the introduction of several traditional two-dimensionalspatial spectrum estimation algorithm, By Comparing with traditional MUSIC algorithmsimulation performance determine that the improved MUSIC algorithm is better in theestimation performance than traditional spatial spectrum estimation algorithm, Then, applythe improved MUSIC algorithm to the single point source and double source for simulation analysis combining with the source characteristics of automobile noise source.Finally, this paper perform a experiment to test the prototype idle speed condition ofnoise source identification, The experimental data were imported into traditional MUSICalgorithm and the improved MUSIC algorithm of vehicle main noise source localizationanalysis. Draw a conclusion that either in simulation analysis or actual application, theimproved MUSIC’S estimation performance better than the traditional MUSIC algorithm.