In this paper, we discuss three GVD compensation schemes, including the post-compensation, pre-compensation and hybrid-compensation schemes with considering combined impacts of GVD, Kerr effect and PMD. By means of the split-step Fourier method, we numerically solve the nonlinear coupling equations of two orthogonal polarization modes. With respect to the statistical character of PMD in the optical fiber, we employ the parameters of average eye-opening penalty to evaluate the combined impacts induced by GVD, Kerr effect and PMID. The numerical results are obtained on the base of 1000 times computation with average DGD less than 35% bit duration. Simulations show that, for the 10Gbit/s NRZ system, the GVD pre-compensation scheme performs best with more than 1dB of average eye-opening penalty better than the other two schemes when input power is greater than lOdBm. However, for the 4OGbitJs NRZ system, when input power P0 > 5.0dBm , the GVD post-compensation scheme performs best with more than 1dB average eye-opening penalty better than the other two schemes. This is different than the previous conclusion that GVD hybrid-compensation scheme has best performance without considering the impact of PIVID. We also define the parameter of eye-opening penalty at outage probability 10-5 to reflect the impact of DGD at the trailing of the Maxwellian distribution. The results also verify that GVD pre-compensation performs best in the lOGbitJs system and post-compensation performs best in the 40Gbit/s system. In both lOGbitJs and 40Gbit/s systems, either average eyeopening penalty or eye-opening penalty at outage probability iO indicates that the system performance with the best GVD compensation scheme can be improved with the increased input power up to 10dBm, and the performance will be worse if input power is greater than 13dBm. We analyze this behavior and conclude that PMD can be suppressed by the increased Kerr effect within a certain power range.
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