A robust step-size control algorithm for frequency domain acoustic echo cancellation

The presence of near-end interferences and echo path changes make it essential for an adaptive filter to vary its learning rate according to corresponding conditions. In this paper, a robust step-size control algorithm which is based on the optimization of the square of the bin-wise a posteriori error is proposed. To prevent the adaptive filter from diverging in the presence of interferences, constraints on the filter update are applied. The learning rate expression is derived and then we extend the method to multidelay block frequency domain adaptive filter (MDF) so as to meet the demand of low delay in practical application. An updating strategy for the constraints is proposed as well. Experiments are carried out to demonstrate the superiority of the proposed approach, especially in double-talk and echo path change situations.