Apparatus for cancelling echoes in a duplex digital transmission system.

摘要

A circuit which improves echo cancellers for bidirectional digital transmission systems by cancelling the echo tails of a desired number N of digital symbols, transmitted on the line in the last N signalling periods. It consists of one part which effects in a simplified manner the summation of the last N transmitted symbols, so as to ease the system implementation by an integrated circuit, and of another part which computes the estimated echo-channel pulse-response. The results are multiplied by one another to obtain the estimated echo-signal.