How Fibre Optics Bring Holiday Entertainment to Our Screens
   
  Fibre optics has revolutionised many sectors of the economy, and television entertainment has not been left behind. Fibre optic systems are now replacing coaxial cables for local distribution within a CATV network. In the past, the analogue and digital transmissions were operated separately using different optical fibres but as the CATV systems grow and expand, new designs combine both analogue and digital signals for transmission using the same fibre by incorporating wavelength-division multiplexing. This increases the number of signals that can be transmitted on one fibre.

CATV systems are now able to support multiple services on one fibre including broadcast television, high-speed internet access and on-demand entertainment (video). All these services are distributed through a fibre optics network to an optical node which will then convert and distribute the electrical signal to subscribers through a coaxial cable connection. The CATV system will also require a return path network to enable it to handle data from the internet through cable modems.

Most CATV systems make use of both single mode and multimode signals within the same network for different areas. The single mode fibre is mainly used to distribute signal from the main office to optical nodes from which it is then converted to multimode for further distribution. Where the CATV systems want to serve fewer subscribers with higher quality signals, they can bypass already installed coaxial cables and connect directly to the local nodes. This is done using an overbuild architecture that requires lots of single mode fibre in the backbone.

CATV systems that make use of fibre optics require many different types of equipments and products for proper installation and distribution. These include single mode and multimode distribution cables, ruggedized cable assemblies and loop test fixtures. Other common materials required are cassette modules, couplers and splitters. The installation of a fibre optic cable, whether it is underground or overhead, will require specialised equipment like cable jets that can handle cable diameters ranging from 0.8mm to 40mm, hydraulic power packs and cable feeders amongst others.

The biggest advantage of using fibre optics for CATV systems instead of the old copper system is that fibre is much more reliable than copper. The signal strength and quality is much more improved therefore customers are able to get higher quality services. Fibre optic also allows for distribution of many signal frequencies within one fibre thus the CATV systems can now distribute more television content to their clients. On top of that, CATV systems can now also provide high speed internet connections to interested clients through the same fibre.