Adaptive echo canceler undoing adaptations made during double-talk

摘要

To remove the echo of a received signal from a local input signal, an echo canceler adaptively estimates the transfer characteristics of the echo path. When a double-talk condition is detected, the echo canceler reverses the adaptation process and returns to a set of estimated transfer characteristics that were in use before the double-talk condition began. Imperfect echo cancellation due to incorrect estimation caused by double-talk is thus prevented inexpensively.