Enhancement of hands-free telecommunications

Hands-free operation is an important feature of many communication terminals such as telephones and conferencing systems. In general, the quality of speech from a hands-free terminal is degraded by ambient noise and by acoustic echo. This paper presents some of the activities in acoustic echo control of a cec Esprit consortium. A short description is given of a database collected specifically for testing acoustic echo cancellers and of a simple methodology for comparative evaluation of adaptive acoustic echo control methods. Eight methods have been investigated so far. Annotated bibliographies are given for each method and comparative performance results are presented.