SYSTEMS ASPECTS OF RAMAN FIBER AMPLIFIERS

Two distinct operating regimes for Raman amplification are identified. In the first case, distributed Raman gain in standard system fibre is used to improve the end-to-end system performance, as demonstrated with the reduction of the loss of a 100 km link of dispersion-shifted fibre from 21 dB to only 13 dB. In the second case, high index difference small core optical fibres have been developed for use as discrete Raman amplifiers, such as transmitter power amplifiers in transmission systems. The saturation performance of the amplifier has been investigated and shows promise for high efficiency high power operation.