Echo cancellation in the network for data applications

摘要

A network-based CODEC (coder-decoder) includes an echo canceler. This CODEC recognizes the presence of a data call by detecting predefined signaling portions of a modem handshaking process. For each detected data call, the CODEC uses a stored channel model for performing echo cancellation during the data call. The CODEC trains off-line during selected segments of the modem call and then stores the new channel model for use in a future data call.