Efficient massive multichannel active noise control using wave-domain adaptive filtering

Multichannel acoustic active noise control (ANC) systems are increasingly being developed in order to enlarge the spatial extend of the quiet zone. This paper discusses the physical background of an ideal ANC system for noise sources outside and within the ANC system. This idealized system can be realized reasonably well with a high number of channels (massive multichannel ANC). It is shown that the typically applied adaptation algorithms have fundamental limitations in the context of massive multichannel ANC. The versatile framework of eigenspace and wave-domain adaptive filtering is proposed as solution to these. Simulation of a massive multichannel ANC system illustrates the successful application of the proposed concepts.