Research On Active Noise Control Algorithm For Vehicle Interior Noise

With the development of high-speed vehicle design,vehicle interior noise problems have become increasingly severe.It will not only fatigue and agitate the drivers,but also damage the hearing system of the drivers and passengers,reduce their attention,and increase the probability of accidents.Thus,studying vehicle interior noises and control method has theoretical and practical significance.The least mean square(LMS)algorithm has won a wide range of theoretical research and engineering applications in the field of low frequency noise reduction with simple computation,less calculation as well as stability.Because of the constant step size parameter and the tap-length,LMS algorithm has inherent defects of unable to balance convergence speed and steady-state error.In view of the defects of the LMS algorithm,two improved active noise control algorithms are proposed for the vehicle interior noise control,including iterative variable step size LMS algorithm and variable tap-length LMS algorithm.The iterative variable step size LMS algorithm constructed a modified nonlinear function between the iteration time and the step-size,making sure the algorithm has great step-size to accelerate the algorithm convergence speed in the initial stage,and small step-size to reduce the steady-state error when tending to convergence.This can ensure that the algorithm has fast convergence speed and low steady-state error.The variable tap-length LMS algorithm can ensure the tap-length keeps near optimal tap-length,which can overcome the additional error caused by choosing the wrong order result and the large quantity calculation of the traditional LMS algorithm.It can greatly reduce the amount of computation,and obtain fast convergence speed and low steady-state error.Under the condition of stationary road vehicles,collected vehicle interior noise signals,by respectively using the LMS algorithm and two proposed algorithm based on vehicle interior noise active control,we take control of acquired the vehicle interior noise.The results show that the iterative variable step size LMS algorithm based on active noise control of vehicle interior noise and the variable tap-length LMS algorithm based on active control of vehicle interior noise both have a certain performance improvement on convergence speed and steady-state error compared with the traditional LMS algorithm.Those two algorithms have better convergence speed and low steady-state error,they are effective active noise control algorithms.