We adopt the worst channel equalization (WCE) scheme to compensate polarization mode dispersion (PMD) in wavelength-division-multiplexing (WDM) systems. The degree of polarization (DOP) of single state of polarization (SOP) optical signal is used as the feedback signal of the PMD compensators, and the particle swarm optimization (PSO) algorithm is used as the searching algorithm. Simulation results show that the DOP of RZ format of the worst-performance channels after compensation is greatly improved, and the PSO algorithm is successfully experienced into adaptive multi-stage PMD compensators in a 40-Gb/s optical WDM communication system. The WCE scheme is an effective way for PMD compensation in WDM system.
We propose an adaptive polarization-mode dispersion (PMD) compensation system in which the minor axis of the degree of polarization (DOP) ellipsoid in receiver is used as feedback signal, and the length of the DOP ellipsoid is optimized through the particle swarm optimization (PSO) searching algorithm to compensate PMD. The operation of adaptive equalization is successfully demonstrated by 40 Gb/s transmission system numerically. Furthermore, we show that using DOP ellipsoid as feedback signal and PSO as searching algorithm, the first and higher order PMD can be compensated effectively.