Mode-Domain Spatial Active Noise Control Using Multiple Circular Arrays

Noise control and attenuation over a sizable space requires uniformly distributed microphones and loudspeakers, which limits the system's viability in practice. In this paper, we propose a mode-domain active noise control (ANC) system using a simple microphone and loudspeaker array structure. We introduce few circular microphone and loudspeaker arrays to first transform a sound field into circular expansion mode coefficients and then combine them to calculate 3D mode coefficients, which are then processed in an adaptive algorithm to attenuate an undesired noise field in 3D space. Experimental results indicate that our proposed method gives comparable noise attenuation performance compared to a conventional method, which uses an unfeasible array structure. Furthermore, the proposed method shows better noise attenuation performance than a conventional temporal frequency domain ANC system.