Active speech control using wave-domain processing with a linear wall of dipole secondary sources

In this paper, we investigate the effects of compensating for wave-domain filtering delay in an active speech control system. An active control system utilising wave-domain processed basis functions is evaluated for a linear array of dipole secondary sources. The target control soundfield is matched in a least squares sense using orthogonal wavefields to a predicted future target soundfield. Filtering is implemented using a block-based short-time signal processing approach which induces an inherent delay. We present an autoregressive method for predictively compensating for the filter delay. An approach to block-length choice that maximises the soundfield control is proposed for a trade-off between soundfield reproduction accuracy and prediction accuracy. Results show that block-length choice has a significant effect on the active suppression of speech.