CATV Series
Hybrid fibre-coaxial (HFC) is a telecommunications industry term for a broadband network which combines optical fibre and coaxial cable. It has been commonly employed globally by cable TV operators since the early 1990s. See diagram below for a typical architecture for an HFC Network. HFC Network Diagram The fibre optic network extends from the cable operators¡¯ master headend, sometimes to regional headends, and out to a neighbourhood¡¯s hubsite, and finally to a fibre optic node which serves anywhere from 25 to 2000 homes. A master headend will usually have satellite dishes for reception of distant video signals as well as IP aggregation routers. Some master headends also house telephony equipment for providing telecommunications services to the community. A regional or area headend/hub will receive the video signal from the master headend and add to it the Public, Educational and/or Governmental (PEG) channels as required by local franchising authorities or insert targeted advertising that would appeal to a local area. The various services are encoded, modulated and upconverted onto RF carriers, combined onto a single electrical signal and inserted into a broadband optical transmitter. This optical transmitter converts the electrical signal to a downstream optically modulated signal that is sent to the nodes. Fibre optic cables connect the headend or hub to optical nodes in a point-to-point or star topology, or in some cases, in a protected ring topology. |
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