Design Of Noise Source Visual Locating System Based On LabView

Accurately locate the location of the sound source is the key to noise control.With the development of signal processing and computer technology,it is technically possible to identify and locate the noise source technically.The noise source identification algorithm is used to process the sound pressure data on the computer to obtain the sound source distribution map,and merges with the background image to form a sound source distribution map that includes the background,so as to achieve the purpose of visual positioning of the sound source.Beamforming is a commonly used method of noise source identification,which contains many algorithms such as traditional delay and sum algorithm,cross-spectral imaging beamforming and deconvolution approach for the mapping of acoustic sources(DAMAS)appearing in recent years.The traditional delay and sum algorithm is to receive signals through sensors and then delay,weight and sum the signals received by the sensors,thereby increasing the desired signal and decreasing the interference signal to achieve the purpose of signal identification and positioning.The advantage of this algorithm is the high computational efficiency and the short time required to locate the noise source,but the spatial resolution is low.However,DAMAS algorithm is to establish the convolution relationship between the cross-spectral imaging beamforming output and the actual sound source distribution and point spread function(PSF)matrix,and then deconvoluted by different methods to get the real sound source distribution,in order to achieve accurate positioning of the noise source.Since this technique obtains a strong spatial distribution of sound sources,its spatial resolution is high.However,the calculation takes a long time because of the large amount of calculation.Therefore,in practical application,the corresponding algorithm should be selected according to the corresponding occasion and demand.In order to enable engineers to quickly and conveniently "see" the location of the real sound source,based on the traditional beamforming technology and DAMAS algorithm,based on LabVIEW platform developed by NI company,this paper developed a set of noise source visual locating system.The system can achieve sensor calibration,sound pressure data acquisition and processing,visual positioning,real-time positioning and so on.The system has built-in three different noise source recognition algorithms,so that the system can be used for visual positioning on different occasions,and the system provides a real-time positioning module that enables the system not only to visually locate the stationary sound source,but also to track the position of a moving sound source or an unsteady sound source in real time.Firstly,the paper introduces the principle of several important noise source identification algorithms in detail,and compares the performance of the above algorithms from two aspects of spatial resolution and computational efficiency through numerical simulation,and determines the specific algorithm adopted by the system.Secondly,introduces the hardware design of the system,including the system's hardware composition and its choice.Then the software design of the system is introduced emphatically including the overall structure of the software,the programming method and functions of each module and the use of important technologies.At last,the system verifies the feasibility of visualization and real-time positioning through experiments and verifies the practicability of the system and the correctness of the results obtained.