Research And Implementation Of Multi-array Audio Signal Synchronous Acquisition And Positioning Algorithm

Sound source localization technology is widely used in car whistle capture,large mechanical failure detection,newborn fetal sound detection,and underwater sound source localization.The microphone array technology can significantly improve the sound quality and the accuracy of sound source localization.However,the array structure of multi-array microphones and the synchronization of signal acquisition affect the accuracy of positioning.The synchronization error of its acquisition will eventually be mapped to the calculated phase error.As a result,the resolution is reduced,and the complexity of the multi-array microphone calculation will affect the real-time performance of the data solution.The specific work of this paper is as follows:First of all,in order to improve the accuracy of three-dimensional localization of sound sources,the structure of a single sound source array was optimized,the number of single arrays was increased,and the placement method between multiple single arrays was improved.The increase of the array makes the measurement distance of the sound source longer,and can effectively reduce the spatial positioning error of the sound source by the single-array sound source localization system.Secondly,in order to improve the influence of noise and reverberation on the sound source localization system,this paper proposes a generalized cross-correlation algorithm based on dithering technology and improved weighting function.The noise removal ability of the algorithm is modeled and simulated by MATLAB.The simulation results show that the algorithm has a good correlation with sharp peaks,and can reduce the signal-to-noise ratio by 5d B under the same positioning accuracy.Under the same signal-to-noise ratio,the positioning accuracy of the sound source can be improved by 10%.On this basis,the multi-array joint sound source localization scheme is optimized,and the Kalman filter algorithm is used in the calculation to further improve the positioning accuracy.Finally,a hardware verification platform was built to verify the multi-array joint sound source localization algorithm.When designing a single-array hardware verification platform,a five-element cross microphone array was selected and an audio signal synchronous acquisition module was homemade.FPGA was used as a data processing platform to take full advantage of the advantages of FPGA high-speed parallel processing of data.And on the basis of the single-array hardware platform,the multi-array hardware verification platform is extended,and the IP core is written in Verilog language to realize the synchronous acquisition of audio signals between multiple arrays on the physical layer.Experimental results show that under the same signal-to-noise ratio,the accuracy of the sound source position of the multi-array joint sound source localization algorithm is more than doubled.