Patent ID: 6449361
Filing Date: 2002-09-10
Classification: H04M

Abstract:
A method of respectively controlling an acoustic echo canceller for providing a first echo cancellation signal by subtracting a first echo replica signal from a transmit signal and a hybrid echo canceller for providing a second echo cancellation signal by subtracting a second echo replica signal from a receive signal, the method comprising the steps of:a first step of determining whether a learning operation of said acoustic echo canceller is permitted or not based on a level of the second echo cancellation signal provided by said hybrid echo canceller; a second step of determining whether a learning operation of said hybrid echo canceller is permitted or not based on a level of the first echo cancellation signal provided by said acoustic echo canceller; a third step of performing a speech detection based on the level of said first echo cancellation signal; a fourth step of performing a speech detection based on the level of said second echo cancellation signal; a fifth step of detecting a double talk condition based on a result of the speech detection performed by said third step and a result of the speech detection performed by said fourth step; a sixth step of controlling the learning operation of said acoustic echo canceller based on a determination made by said first step and a result of the double talk detection performed by said fifth step; and a seventh step of controlling the learning operation of said hybrid echo canceller based on a determination made by said second step and the result of the double talk detection performed by said fifth step.