Inspection of the secondary path modeling in active noise control from the viewpoint of channel identification in stereo acoustic echo cancellation.

Abstract

The similarity between the identification of secondary path in feedforward active noise control and the channel identification in stereo echo cancellation is revealed in this paper. Accordingly, the convergence behavior of the ANC system can be analyzed by investigating the joint auto-correlation matrix of the reference and the filtered reference signal. It is proved that the straightforward secondary path modeling can be carried out without the injection of any additive noise as long as the control filter is of a sufficiently long length. Furthermore, by taking advantage of the time-varying characteristic of the control filter, effective modeling of the secondary path can even be achieved without any restriction on the control filter length.