Reduced SNR handshake signaling in ADSL systems

摘要

In an asynchronous digital subscriber line (ADSL) system comprising a central office ADSL Terminating Unit (ATU-C) in bi-directional overlap spectrum discrete multitone (DMT) communication with a remote ADSL Terminating Unit (ATU-R), a method is provided in accordance with the present invention. The method comprises the step of transmitting a first handshake tone at either a first DMT tone or a second DMT tone based at least in part on a distance between the ATU-C and ATU-R. In one embodiment, the first handshake tone is transmitted at the first DMT tone when the distance between the ATU-C and ATU-R is less than 6.2 kilometers and the first handshake tone is transmitted at the second DMT tone when the distance between the ATU-C and ATU-R is greater than or equal to 6.2 kilometers.