Optical Fibre Link Emulator

This project was completed for the University of Bath and involved experimental simulation of an optical fibre link. In real world environments signals travelling through optical fibres suffer a number of different effects. It is clear that signal attenuation is the most obvious of the effects but in practice we also find that signals are also subjected to switching attenuations (as they pass over connections and are routed), polarisation mode dispersion and polarisation mode losses. In order to study these effects many kilometres of fibre and highly expensive test systems are required.
The University wanted a simple low cost system which could demonstrate some of these effects, which could be used as a teaching aid. The final system was able to demonstrate the effects of polarisation mode losses along different optical fibre types as well as simple switching losses through switching. Rapid automated switching and control through a GPIB network were required in order to vary the polarisation plane of laser light whilst losses were recorded and calculated on oscilloscopes.