Multi-carrier data transmissions system using an overhead bus for synchronizing multiple remote units

摘要: A bi-directional data transmission system that facilitates communications between a central unit and plurality of remote units using frame based discrete multi-tone (DMT) scheme is disclosed. The has multiplicity subchannels including an overhead bus. In method aspect the invention, frames transmitted from are synchronized at unit. When selected desires to initiate communications, it loop times own clock transmits initiated synchronization signal over dedicated subchannel in responds with centrally contains information indicative boundary phase shift required synchronize first other currently communicating by shifting outputs amount indicated signal. This synchronizes boundaries outputted output arranged occur such various remotes substantially coincide when they received Specific modem designs suitable for implementing also described.