Optical fibre communications

Abstract

We live in an age of rapidly evolving new technologies, one of which is optical fibre communications. During these last two decades optical communication using fibres, has had a major impact on telephone systems, computer interconnections and instrumentation. Fibre links provide several major advantages over conventional communication systems. These include immunity to electromagnetic interference, thinner and lighter cables, lower transmission losses and potential kilometre-long link capabilities extending to the gigahertz region. The advances which have led to the evolution of optical communication using fibres result from major improvements made in past decades in semiconductor lasers and light-emitting diodes, detectors and fibres. Optical communication is now at the threshold of major commercial exploration with world-wide activity in engineering and field trials. The aim of this thesis is to bring together material dealing with the semiconductor components and fibres used in optical fibre communications. It also deals with an experimental point-to-point data link, concentrating mainly on the design and construction of a light-emitting diode transmitter, optical receiver and error-rate measurement circuitry. A novel modulation technique, the self-clocking encoding scheme, is also implemented.