Noise reduction performance of active noise control with barrier using theoretical control filter

Abstract

The external noise is a problem closely related to modern society. There are two ways of noise control methods. One is passive noise control that uses absorbing or insulating materials. The other is active noise control that generates the sound of the opposite phase with the noise by the secondary speakers. Since the effective frequency band of the noise reduction in each method is different, using both methods has been researched to expand the controllable frequency band for dealing with various noise. In order to apply active noise control, the information over the control region is required to obtain a control filter of control speaker. However, the general method that arranges the microphones over the control region can be the obstacles to the user, therefore the other method is needed to obtain the control filter. One way to obtain the control filter without the arrangement of the microphones is using the theoretical model and the control filter can be obtained relatively easily based on the theoretical model. Therefore, the theoretical model is generally used to estimate the maximum performance by simulation. However, there is less research for studying the applicability of the ANC system with a finite noise barrier based on the theoretical model and the verification of the control filter is required by investigating noise reduction performance in the experiment. In this paper, the control filter is obtained based on the theoretical model and noise reduction performance is investigated in the experiment for verification of the control filter.