Acoustic Echo Suppression

摘要

A controller for an echo suppressor configured to suppress a residual echo of a far-end signal included in a primary error signal, the controller adapted for operation with a primary adaptive filter configured to form a primary echo estimate of the far-end signal included in a microphone signal and an echo canceller configured to cancel that primary echo estimate from the microphone signal so as to form the primary error signal, the controller comprising: a secondary adaptive filter configured to form a secondary echo estimate of the far-end signal comprised in the microphone signal; and control logic operable in at least two modes selected in dependence on a convergence state of the primary adaptive filter, the control logic being configured to control activation of the echo suppressor in dependence one or more transient or steady state decision parameters.

主权项

1. A controller for an echo suppressor configured to suppress a residual echo of a far-end signal included in a primary error signal, the controller adapted for operation with a primary adaptive filter configured to form a primary echo estimate of the far-end signal included in a microphone signal and with an echo canceller configured to cancel that primary echo estimate from the microphone signal so as to form the primary error signal, the controller comprising:
a secondary adaptive filter configured to form a secondary echo estimate of the far-end signal included in the microphone signal; a coherence estimator configured to form a first measure of coherence between the microphone signal and the primary error signal, and a second measure of coherence between the microphone signal and the primary echo estimate; and control logic being configured to:
in a first mode selected when the primary adaptive filter is in a non-converged state, combine the microphone signal and the secondary echo estimate so as to form a transient decision parameter indicative of a state of the microphone signal and, in dependence on the transient decision parameter, control activation of the echo suppressor; andin a second mode selected when the primary adaptive filter is in a converged state, combine the first and second measures of coherence so as to form one or more first steady state decision parameters indicative of a state of the microphone signal and, in dependence on said one or more first steady state decision parameters, control activation of the echo suppressor.