Systems and methods for adapting estimated secondary path

Abstract

A noise-cancellation system with secondary path adaptation, includes: a noise-cancellation filter configured to receive a reference signal representative of a source of noise within a predefined volume and generating, based at least in part on the reference signal, a noise-cancellation signal that, when transduced by a speaker, produces a noise-cancellation acoustic signal that reduces noise in a cancellation zone within the predefined volume; a secondary path estimation filter configured to receive an input signal and to implement an estimate of secondary path transfer function, the secondary path transfer function being a transfer function between the speaker and a cancellation zone, the secondary path estimation filter outputting an output signal based, at least in part, on the estimate of the secondary path transfer function and the input signal; an adaptive module configured to adjust coefficients of the noise-cancellation filter according to a first adaptive algorithm, based, at least in part, on the estimated output signal; and an secondary path adaptive module configured to adjust coefficients of the secondary path estimation filter according to a second adaptive algorithm, wherein a rate of adaptation of the second adaptive algorithm is based, at least in part, on a coherence between the reference signal and an error signal representative of residual noise within the cancellation zone.