Simulation And Research On Phased-microphone Array Noise Identification On The Basis Of Beamforming

With development of the social productivity and national economy, the noise pollution of traffic is influencing people's life, work and study more and more seriously. Controlling the noise source is the most basic and effective method to reduce noise. Using noise identification, we can know the position distribution of noise, analyze its characteristic and offer the theoretical foundation for reducing the noise.This paper compared several kinds of traditional methods, then chose the array noise source identify method. According to the characteristic of the object, adopted the beamforming algorithm.According to the principle of time delay of beamforming, calculated the mathematical model of array receiving noise source and simulate it, then gained the figure of scanning. The results indicate that the beamforming has higher precision, but petal and bar petal can appear when the frequency of noise is high. For this reason, on the basis of traditional methods of the beamforming, this text had put forward the space scan algorithms basing on direction matrix of the array, calculated the mathematical model of array receiving noise source and simulated it. The results had much higher precision than the traditional beamforming, removed the influence of petal and bar petal of the traditional beamforming and verified the feasibility of this idea in theory, then put the equation into the projects.The engineer equation is the first type Fredholm integral equation. This paper solved the reversed problem of physical&mathematics by artificial neural network. Firstly, transformed the equation into non-linear and single objective mathematics model of optimization, then solved the problem with continuous Hopfield neural network, then chose a set of suitable parameters and built the energy function, and output the solution when the energy function converged to the global minimum. Finally, proved accuracy and feasibility of the algorithm on the basis of the classical example, solved the equation of engineer, and analyzed the result.This text successfully solved the classical example of Fredholm equation, which is break-through at mathematics, have much realistic and project value.