Realisable Chernoff bound filters for digital optical transmission

Optical telecommunications involves signal and noise processes which differ significantly from their familiar conventional electrical counterparts. The authors show that by adopting a modified Chernoff bound (MCB) on error probability as the basis for numerical optimisation of preselected low complexity structures one can devise realisable filters offering performance which is very close indeed to the strict optimum established using variational calculus techniques. They outline the general strategy, present examples of specific filters with their corresponding time and frequency domain responses and illustrate the degree of improvement these novel filters offer compared with their conventional counterparts. They conclude that without recourse to undue increase in complexity useful benefits can accrue for practical high bit rate digital optical transmission systems if post-detection receiver filters are adopted designed in accordance with the MCB minimisation technique