Active Noise Control of a Moving Evaluation Point in One Dimensional Acoustic Field : 2nd Report, Proposal of an Improved Noise Controller Applicable to a Rapid Moving Evaluation Point

Abstract

A basic noise control system applicable to a moving evaluation point was proposed in the previous report, and its effectiveness was examined numerically and experimentally. Although the results showed that the proposed system is effective, it can only handle the case of slow evaluation point velocity. This restriction seemed to be due to the slow convergent speed of the adaptive filter. In this paper the cause of restriction is examined in detail, and an advanced control system is proposed. The features of the proposed system are as follows : 1) Improved feedback controller where main filter is less affected by the movement of the evaluation point. 2) Introduction of IIR filter together with the learning identification method to the error path identifier. The new system is examined both in simulation and experiment and shows great improvement compared with the basic model.