Research On Error Modeling For Active Noise Control

In recent years,with the continuous advancement and development of industrial technology,domestic noise and industrial noise are also increasing.Noise pollution will have a huge impact on people’s quality of life,working environment and physical and mental health.The traditional passive noise control(such as sound absorption,sound insulation,vibration isolation,etc.)has its inherent shortcomings in the control of low-frequency noise,and the passive noise reduction system is large and difficult to arrange;and active noise control is used as a new Noise technology has become a research hotspot in the field of noise control because of its fast convergence speed and wide application range.First,this paper introduces the principle and structure of the active noise control system,and analyzes the advantages and disadvantages of different system structures.Next,by analyzing the basic structure of the filter and the common adaptive algorithm,the principle of the adaptive filter based on the LMS algorithm and FIR filter structure is studied,and the derivation process of the adaptive fllter is given.Then based on the above foundation,the basic principle and derivation process of FxLMS algorithm were studied,and the simulation experiment of secondary path identification and FxLMS algorithm was carried out on matlab2016a platform.Then,in view of the lack of FxLMS algorithm to reduce noise in disturbed noise,the basic principle of error modeling was introduced,and error modeling was introduced into FxLMS algorithm,and the RDEM-FxLMS algorithm was proposed,the noise reduction effect of the FxLMS algorithm in the noise reduction scene with disturbance noise is optimized.Next,based on the adaptive active noise control hardware platform with the TMS320C6748 processor as the core,the software driver is implemented,including the initialization of the DSP main chip and its peripheral modules,the clock synchronization between the hardware modules such as the AD sampling chip and the DA output chip With data transmission,etc.The implementation of the hardware platform facilitates the practical application of noise reduction algorithms.By transplanting the FxLMS algorithm to the hardware platform,the noise reduction experiment in the actual environment was completed,and a 9dB noise reduction effect was achieved in single-point noise reduction.Finally,in order to gain a deeper understanding of the performance of the hardware platform in different sound field environments,a sound field simulation laboratory was set up to simulate sound field environments with different noise characteristics.This is considering that going to the actual field test noise reduction platform will increase the cost,and some special sound field environments do not have the conditions for field test.Then in the established sound field simulation laboratory,the background noise and the noise of the simulated sound field were collected,the RMS values of the two noises were analyzed,and the constructed sample data was clustered using the k-means algorithm to guide the layout of the hardware platform In order to achieve regional noise reduction more clearly and in a targeted manner.