Nonlinear polarization mode dispersion in optical fibers with randomly varying birefringence

Summary form only given. Random fluctuations in birefringence along an optical fiber result in polarisation-mode dispersion, which degrades the transmission rate in both NRZ and soliton systems. Recently, we proposed two physical models to study the polarization-mode dispersion (PMD) when the axes of birefringence rotate randomly. In the first model we allow the birefringence orientation to vary randomly but the strength fixed; in the second model we assume that the birefringence orientation and strength have a two-dimensional Gaussian distribution. We show that the coupled nonlinear Schrodinger equation which describes wave evolution over long lengths along a communication fibre can be reduced to a Manakov equation.