Direct fully adaptive active noise control algorithms without identification of secondary path dynamics

This paper is concerned with a fully direct adaptive feedforward control algorithms for general active noise control (ANC) when all the path dynamics are uncertain. To reduce the actual canceling error, two artificial errors are introduced and are forced into zero by adjusting three adaptive FIR filters in an on-line manner. Unlike other conventional approaches, the adjusted parameters do not need to converge to the true FIR parameters of the primary and secondary path dynamics but only to some constants, then the reduction of the two errors can achieve the canceling at the objective point. The convergence is investigated and simplified algorithms are also given for implementation. The effectiveness of the proposed algorithm is validated in experiments of ANC using an air duct.