SPATIAL ACTIVE NOISE CONTROL WITH THE REMOTE MICROPHONE TECHNIQUE: AN APPROACH WITH A MOVING HIGHER ORDER MICROPHONE

Spatial active noise control (ANC) aims to reduce unwanted acoustic noise over a continuous spatial region by generating an anti-noise field with secondary loudspeakers. Conventionally, spatial ANC is achieved by using complex error microphone arrays such as grid or spherical geometry, which are impractical and obstruct the users to enter the quiet region. Recently, the remote microphone technique has been introduced to spatial ANC systems without using error microphones inside the region of interest. However, this technique still requires an error microphone array during the tuning stage. In this paper, we further improve the remote microphone technique by introducing a spatial sound field recording method with a moving higher order microphone for the noise field recording (tuning stage) as well as secondary channel estimations (control stage). This eliminates the requirement for impractical microphone array geometries, typically required in existing spatial ANC solutions. The experimental data based simulation demonstrates the effectiveness of the proposed method on noise reduction over space with its feasible array design.