Radial compensation for sound field control in enclosed space

This study proposes a method for sound field control in an enclosed space. In spaces that are acoustically damped, e.g. a room with absorbent walls, the soundfield is often modelled using a complex wavenumber, which is different to that in a free field. Conventional wave-domain methods fail to control the sound field when the wavenumbers of the target and the reproduced fields are mismatched. In this study, a radial compensation, matching the wavenumbers at a certain radius in the target and the reproduced fields, is proposed. The results show that the proposed method can achieve a listening area that extends over an entire sphere, whereas the conventional method restricts this to only the control points at the boundary. Alternatively, applying the radial compensation to multiple radii with a least square method can also achieve a spherical control area but with decreased control accuracy.