Fiber to the home office (FTTHO) architecture employing multiple wavelength bands as an overlay in an existing hybrid fiber coax (HFC) transmission system

A method of operating a hybrid fiber coax transmission system, comprising the steps of:

• directing, via a fiber portion of the transmission system, first wavelength division multiplexed (WDM) optical signals from a headend to a plurality of fiber nodes for demultiplexing and conversion to respective electrical signals, said first WDM optical signals being in a first wavelength band;
• transmitting said respective electrical signals, via a coaxial cable portion of the transmission system, to homes of individual subscribers;
• and
• exchanging, via a fiber portion of the transmission system, second WDM optical signals between a headend and at least one of said fiber nodes,
• demultiplexing said second WDM signals at said at least one fiber node and transmitting at least one demultiplexed wavelength channel to at least one of said individual subscribers via an optical communication link, said second WDM optical signals being in a second wavelength band different from said first wavelength band.

A method of upgrading a hybrid fiber coax transmission system having a plurality of optical nodes operative to receive wavelength division multiplexed (WDM) optical signals from a headend and to direct demultiplexed optical signals in a first wavelength band to respective groups of optical access units, each group being associated with a corresponding optical node and each optical access unit being adapted to convert said demultiplexed optical signals to electrical signals for distribution to respective subsets of subscribers via coaxial cable, said method comprising the steps of:

• replacing a first of said optical access units with a plurality of multiple wavelength band optical access units, each said multiple wavelength band optical access unit being adapted to receive, via a fiber portion of the transmission system, demultiplexed optical signals in said first wavelength band and in a second wavelength band, to convert optical signals in said first wavelength band to electrical signals for transmission to a subset of residential subscribers previously associated with the first of said optical access units, and to exchange demultiplexed optical signals in said second wavelength band with at least one subscriber of said subset of residential subscribers previously associated with the first of said optical access units to thereby accommodate higher bandwidth business communication services;
• configuring a first of said optical nodes to receive WDM optical signals in said first and second wavelength bands and to direct demultiplexed optical signals in said first and second wavelength bands via a fiber portion of the transmission system to at least one of said plurality of multiple wavelength band optical access units;
• establishing an optical link between said at least one of said multiple wavelength band optical access units and said at least one subscriber of higher bandwidth business communication services, said optical link being dimensioned and arranged to optically exchange information, transmitted via optical signals of said second wavelength band, between said headend and said at least one subscriber;
• and
• using existing coaxial cable links to exchange signals between said at least one of said multiple wavelength band optical access units and lower bandwidth capacity requesting subscribers of a corresponding subset of subscribers.