Patent ID: 6947552
Filing Date: 2005-09-20
Classification: H04B

Abstract:
1. An echo canceler using an adaptive filter to generate an echo replica signal from a received far-end signal and using the echo replica signal to cancel an echo component in a near-end signal, thereby generating a transmit signal, the adaptive filter adapting to changes in the echo path by updating tap coefficients, the echo canceler comprising: a double-talk detector for detecting at least a double-talk state; an echo path change detector for estimating an echo path loss on an echo path by which the echo component reaches the near-end signal from the received far-end signal, thereby detecting echo path change; and a control unit for controlling adaptation in the adaptive filter according to detection of the double-talk state by the double-talk detector and detection of echo path change by the echo path change detector by suspending or abating updating of tap coefficients when the double-talk detector detects the double-talk state, provided the echo path change detector does not detect echo path change; and by permitting the tap coefficients to be undated normally when the double-talk detector detects the double-talk state if the echo path change detector also detects echo path change.