Abstract
We propose a pre-inverse active noise control (PIANC) in order to solve the unstable problem on a Filtered-x ANC (adaptive noise control). The PIANC uses the flat delayed signal instead of a filtered input signal. However, since the conventional PIANC uses a series adaptive system to estimate the inverse transfer function of a secondary path, the noise reduction ability is degraded due to bias error. Therefore, this paper introduces an auxiliary filter into the estimation of the inverse transfer function of the secondary path. The proposed method configures the bias free structure by taking advantage of the delay in the primary path. This paper shows that the proposed method has possibility to be superior to a Filtered-x ANC by simulation results. In addition, the proposed method is implemented by a DSP (digital signal processor).
