Method and apparatus for coordinating multi-point to point communications in a multi-tone data transmission system

In a bi-direction data transmission system that facilitates communications between a plurality of remote units and a central unit using a symbol-based discrete multi-carrier transmission scheme that has a multiplicity of discrete sub-channels provided for facilitating upstream communications between the plurality of remote units and the central unit, a method of informing the central unit of the transmission requirements of a remote unit, the method comprising the steps of:

• in a normal polled transmission mode, transmitting a communication access request from a selected first remote unit to the central unit during a selected one of a plurality of symbol periods in a sequence, the communication access request not including a unique remote unit identifier identifying the selected first remote unit;
• responsive to receiving a command from the central unit indicating that a fast access transmission mode is available, transmitting the communication access request from the selected first remote unit to the central unit during any of the plurality of symbol periods in the sequence the communication access request comprising a unique remote unit and being transmitted from the selected first remote unit on at least one unused sub-channel using a modulation scheme that does not require equalization to decode at the central unit identifier identifying the selected first remote unit;
• and
• allocating at least one sub-channel to the selected first remote unit in response to the communication access request for facilitating upstream communications between the selected first remote unit and the central unit.