Nonlinear polarization mode dispersion in optical fibers with randomly varying birefringence

The evolution of polarization states are studied in fibers with randomly varying birefringence. A physical model in which the birefringence orientation varies arbitrarily while the birefringence strength is fixed is used to study the evolution of polarization states in fibers with randomly varying birefringence. We show that the coupled nonlinear Schrodinger equation which describes wave evolution over a long length along a communication fiber can be reduced to the Manakov equation with additional terms that describe linear and nonlinear polarization mode dispersion. The coefficients of the linear and nonlinear polarization mode dispersion are the Stokes. parameters and the squares of the Stokes parameter. The implications for numerical simulations of transoceanic communications are discussed.