Acoustic Echo Control with Frequency-Domain Stage-Wise Regression

This letter introduces frequency domain stage-wise regression to acoustic echo control. By approximating the echo path as concatenate short segments in frequency domain, simple regression in the frequency domain can be carried out to estimate the echo contributed by consecutive far-end signal blocks stage by stage. A non-stationarity controlled smoothing factor is proposed alongside the regression procedure to mitigate the increasing variance of estimation when no significant echo but only near-end background noise is present. Experiments are carried out to demonstrate the superiority of the proposed approach, especially in unstable environment.