Ma, FeiZhang, WenAbhayapala, Thushara2019-03-060001-4966http://hdl.handle.net/1885/156995Current active noise control systems can cancel noises in a duct effectively. However, they are insufficient for suppressing complex noise fields in time-varying rooms. This paper develops an active noise control system that can cancel tonal noise fields produced by a primary source in a room. The problem of tonal noise field control is formulated as estimating and canceling the outgoing field on a sphere surrounding the primary source. The proposed system limits the energy of the primary source radiating out of the sphere, thereby creating a global quiet zone inside the room. In addition, it removes the need for online secondary path estimation with reduced influence on desired sound fields in the room. A method for estimating the outgoing field on a sphere is presented, together with a wave-domain algorithm for controlling the outgoing field. Simulations and hardware demonstrations show the proposed system can reduce tonal noise fields in a room and over a wide frequency range.This work is sponsored by the Australian Research Council (ARC) Discovery Projects funding schemes with project Nos. DP140103412 and DP180102375. F.M. is supported by the China Scholarship Council—Australian National University Joint Funding Program.application/pdfen-AU© 2018 Acoustical Society of America2018-0910.1121/1.5055217