Optical Communications

Optical communication systems consist of the following components:

1. Transmitter: Converts and transmits an electronic signal into a light signal. The most commonly used transmitters are semiconductor devices, such as light-emitting diodes (LEDs) and laser diodes.
2. Optical Fibre: Consists of a core, cladding and a buffer which carries to signal in the form of light pulses to the receiver.
3. Receivers: Typically consist of a photo-detector, which converts incoming light pulses into electricity using the photoelectric effect. The photodetector is typically a semiconductor-based photodiode.

There are some challenges associated with optic communication such as the high costs and the skill and expertise required during cable installation and interconnection. However, compared to other mediums, fibre optic cables offer many distinct advantages:

• Speed: Fibre optics allow for data transmission speeds that have never been seen before in previous digital technologies. While copper Internet connections can transfer data at about 50 Mbps, fibre optics can comfortably achieve over 1 Gbps and have been tested successfully at speeds of over 1000 times this.
• Distance: Fibre optics can send data tens of miles with very minimal signal loss. In the case that a distance causes significant signal loss, amplification is simple and easy to achieve. Since these cables use light instead of electricity, interference is nonexistent. Standard electrical communication can be compromised by electric fields; however, light does not react to this type of interference.
• Bandwidth: Fibre optic cabling provides a much higher bandwidth allowing more data to be delivered. In one second, electrical communication can transmit only 10Gb of information (10 billion 0 and 1 signals). In contrast, optical communication can transmit information of up to 1Tb (1 trillion 0 and 1 signals).
• Physical attributes: When comparing the physical aspects of fibre optic cable to other mediums, fibre optic cables have a much lighter weight, a smaller diameter, and the ability to avoid corrosion and rust due to a non-metallic construction. These characteristics place fibre optics at the top of the list for communications in today’s world.

With changes in the demand and availability of new digital technologies, new frontiers are being added to the main fibre-optic technologies including all-optical computing, and intelligent and automated-optical networking.