Frequency‐dependent bursting in adaptive echo cancellation and its prevention using double‐talk detectors

摘要

AbstractEcho cancellation in telephone communications can often be accomplished by using adaptive network echo cancellers. However, under certain circumstances, these generally effective echo cancellers can cause an undesirable bursting phenomenon. In this paper the essential driving force behind bursting is attributed to the correlation between the signal the near‐end is to transmit and the signal the near‐end receives from the far‐end. This correlation and the subsequent potential for temporary destabilization arise as a result of the feedback loop structure of the four‐wire telephone circuit. A new test signal which approximately measures this correlation is proposed for use in the double‐talk detector scheme that is commonly used to halt adaptation before a mishap such as bursti