Optical fibre systems optimally tolerant to transient distortion

Considers a model for a binary optical fibre system based on the use of symbol conditioned moment generating functions (mgfs). Random distortions of the signal element waveform are accommodated by further averaging of the symbol conditioned mgfs. A threshold optimised MCB (modified Chernoff bound) is derived and forms the basis for receiver performance evaluation. Application of variational calculus techniques to the MCB yields a nonlinear differential equation the solution of which is the required optimum filter impulse response. The authors conclude by deriving optimum filters for an optical receiver under a variety of transient distortion and noise regimes, comparing the performance of these with a traditional filter giving a 100% raised-cosine signal spectrum at the output. It is demonstrated that optimum signal designs may be identified showing improved performance and tolerance to transient distortion