A consideration of polarization dispersion determining from a Stokes parameter evaluation

The authors analyze polarization dispersion determined from the Stokes parameter measurement for a single-mode fiber. The polarization state changes are considered for a discrete, tandem fiber model using Poincare sphere representation. As a result, it is found that the differential delay time estimated from the Stokes vectors of output light is not given as the cumulation of zero-mean random values but as positive random values, when random mode conversion exists along a fiber axis. Consequently the polarization dispersion is predicted to increase in proportion to the square root of distance over a 1000-km length