Abstract: A system and method for echo cancellation in a communication system having a digital echo canceller and an analog echo canceller for analog reduction of cross coupling echo components in an analog output signal when in analog form before digital processing by the digital echo canceller. An analog cancellation signal is generated which is substantially the same as the acoustic coupling echo component in the analog output signal before digital processing by the digital echo canceller. The analog echo cancellation signal is combined with the analog output signal to reduce the cross coupling echo component before digital processing by the digital echo canceller.

Abstract: The call-waiting feature is supported on voice-and-data modems (22,25) by causing voice-and-data modems to go into voice-only mode upon receipt of the modem clear-down signal (352-354). A first voice-and-data modem engaged in an initial voice-and-data call with a second voice-and-data modem responds to receipt (202) of a call-waiting signal by generating (204) a replica of the call-waiting signal on the user's audio channel. The first modem responds to a user request (300) to pick up the waiting call by sending (306) the modem clear-down signal to the second voice-and-data modem, going (312) into voice-only mode, and transmitting (314) a waiting-call acceptance signal. The initial call that is placed (332) on hold is thus a voice-only call. While in a voice-plus-data picked-up waiting call, the first modem responds to a user request (400) to reinstate the initial call by again sending (406) the modem clear-down signal, going (412) into voice-only mode, and transmitting (422) a call-resumption signal.