Patent ID: 6980644

Claim:
For use in a transceiver of the type comprising a line driver capable of sending analog transmit signals through a cable, and a line receiver capable of receiving analog receive signals from said cable, and an analog echo canceller capable of cancelling echoes of said analog transmit signals that are present in said analog receive signals by generating an echo canceller current that is equal in magnitude and opposite in phase to a current that represents said signal echoes, a system for adapting said analog echo canceller comprising: an analog echo canceller control circuit capable of changing a first value of the resistance of at least one variable resistor in said analog echo canceller by subtracting from said first value of resistance a second value of resistance equal to the product of the terms μ, p, and tx, where p represents residual uncancelled echo at the output of said analog echo canceller, and where tx represents a transmit signal, and where μ represents a scale factor for converting the product of the term p and the term tx to a quantity expressed in ohms, when the correlation of the term p and the term tx is positive.