Patent ID: 7355964

Claim:
A bidirectional communication system, the system comprising: a first remote unit for communicating with a host unit using orthogonal frequency division multiplexing, the host unit communicatively coupled to a plurality of remote units in a multipoint-to-point configuration; wherein the first remote unit is configured to transmit up to a plurality of tones, the up to a plurality of tones modulated with upstream information using orthogonal frequency division multiplexing; wherein the first remote unit is configured to determine when bandwidth is needed for upstream transmission to the host unit; wherein the first remote unit is configured to transmit a request for bandwidth to the host unit on a first tone of the plurality of tones, wherein access to the first tone is contention-based; and the first remote unit including a modulator for modulating the up to a plurality of tones with upstream information using orthogonal frequency division multiplexing, wherein the modulator is configured to adjust a carrier frequency, a carrier amplitude, and a phase of at least one tone of the up to a plurality of tones such that when any tones are transmitted from the first remote unit and at least one other remote unit of the plurality of remote units, the any tones transmitted from the first remote unit and the at least one other remote unit are orthogonal when received at the host unit.