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Evaluation of Polarisation Mode Dispersion in Longhaul Digital Optical Fiber Transmission System

The paper investigates the birefringence of a single mode fiber. The suitable value of birefringence for fiber application has been identified. Evolution of polarisation mode dispersion (PMD) and its analysis has been presented. An upper bound for the probability of error due to PMD in terms of Chernoff Bound (CB) and Modified Chernoff Bound (MCB) has been evaluated. The further analysis elaborates upon the dependence of mean power penalty on the birefringence of the fiber. The mean penalty dependence on the birefringence of a highly birefringent dispersion shifted fiber at 1.55 μm is calculated. This dependence obeys square law distribution and highlights the need of birefringence of the order of 10-2 in order to have lower penalty due to PMD.