What is Radio Frequency Over Fibre (RFOF)?
Radio Frequency Over Fibre is a way of transmitting radio waves via a fibre optic cable. The Radio Frequency is first converted into light, where it then travels along the fibre optic cable, before being recovered by an Optical Electrical modulator (O/E) and converted back into a Radio Frequency once more. Unlike a traditional copper coax cable, the transmission along a fibre optic cable can travel more than 300ft and is not distance limited. This makes Radio Frequency Over Fibre more applicable to many businesses.
A Radio Frequency Over Fibre consists of 4 parts:
- Light Source/Laser Diode
- Electrical-optical Modulator (E/O) which converts the Radio Frequency into a light beam
- Transmission Medium: This is a single-mode fibre-optic cable. This cable has minimal light reflections to lower attenuation and allows the signal to travel longer distances.
- Optical-electrical Modulator (O/E) which converts the light beam back into a Radio Frequency signal on the receivers side using a photodiode or avalanche photodiode (APD).
Radio Frequency Over Fibre can be categorised as either ‘Radio Frequency Over Fibre (RFOF) or Intermediate Frequency Over Fibre (IFOF).
- RFOF: A RFOF signal with a radio frequency greater than 10GHZ is imposed on a lightwave signal before being transported over the fibre optic cable.
- IFOF: An IFOF with a radio signal frequency less than 10 GHZ is used for modulating light before being transported over the fibre optic cable.
Where can you use Radio Frequency Over Fibre
One of the main uses of RFOF is its ability to provide wireless coverage to ‘dead zones’. These can include tunnels, behind buildings, mountainous areas, inside structures and secluded areas.
Advantages of Radio Frequency Over Fibre
There are many advantages of Radio Frequency Over Fibre. These include:
- Easy installation and maintenance
- Lower cost as a result of easy maintenance, simple installation and low power consumption
- Low risk of noise and electromagnetic interference
- Lower transmission losses
- Large bandwidths
- Radio frequency signals can be sent over large distances without the use of repeaters
- Adaptable with future advancements. Fibre Optics can cope with higher speeds than today’s technology, meaning they are able to be used with future advancements.
- Wireless access: A single antenna can receive any and all wireless communication carried over a fibre optic cable. This includes 5G, cell, Wifi etc…