Multichannel PMD mitigation and outage reduction through FEC with sub-burst-error-correction period PMD scrambling

We study the performance of a novel multichannel polarization-mode dispersion (PMD) mitigation scheme in which forward error correction is utilized with distributed fast polarization scramblers to physically change the PMD of an optical link within each burst-error-correction period. It is shown numerically that the proposed scheme dramatically reduces the PMD outage probability, and that it improves the PMD tolerance for nonreturn-to-zero on-off keying and differential phase-shift keying (DPSK) by approximately 70% and 100%, respectively. The optimal scrambling speeds are determined. The proposed scheme is particularly beneficial to DPSK with a balanced receiver as the optimal decision threshold is the same for all the bits regardless of distortion.