Ranging and round trip delay timing adjustment in a multi-point to point bidirectional communication system

A remote service unit for a multi-point to point communication system, the remote service unit comprising:

• a transceiver communicatively coupled with a host unit in a multi-point to point configuration, the transceiver configured to communicate with the host unit via an orthogonal frequency division multiple access waveform;
• a multi-carrier modem coupled to the transceiver and configured to demodulate downstream information data from the orthogonal frequency division multiplexing waveform based on a Fourier transform algorithm, the multi-carrier modem further configured to modulate upstream information data onto the orthogonal frequency division multiplexing waveform based on an inverse Fourier transform algorithm;
• wherein the multi-carrier modem is configured to adjust a round trip path delay between the first remote unit and the host unit based on a path delay correction received from the host unit;
• and
• wherein the multi-carrier modem is further 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.

A bi-directional communication system, the system comprising:

• a plurality of remote units;
• a multipoint-to-point host unit communicatively coupled with a plurality of remote units in a multi-point to point configuration, the multipoint-to-point host unit including a multi-carrier modem configured to communicate with the plurality of remote units via an orthogonal frequency division multiple access waveform;
• wherein the multipoint-to-point host unit is configured to estimate a round trip path delay correction associated with at least one of the plurality of remote units;
• and
• wherein the multipoint-to-point host unit is configured to adjust the round trip path delay associated with the at least one of the plurality of remote units,
• the plurality of remote units each 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.