Receivers for optical fibre communications

This paper is a review of today´s state-of-the-art in receivers for optical fibre communications, both in practice and in theory. The functions of an optical receiver are discussed, and a detailed description of unity-gain photodiodes is given. The problem of detection in the presence of noise is treated next, and the difference between optical and radio-frequency systems is highlighted. The theory of avalanche photodiodes is summarized, and state-of-the-art devices and their performance described. The final section is a review of the theory of optical receivers, with comparisons of theoretical predictions with practical achievements, especially for the sensitive p-i-n f.e.t. receivers.