Time evolution of polarization mode dispersion in long terrestrial links

Although polarization mode dispersion is well characterized in terms of principal states of polarization (PSP) and of their differential group delay (DGD), both analytically and experimentally, very few data have been published on their time evolution in terrestrial links, where temperature fluctuations are larger than in undersea links. The authors demonstrate strong correlation between temperature fluctuations and evolution of DGD and PSP. Correlation is even stronger in links which include connectors. Also, they report that DGD, as a random function of time, has a Maxwellian distribution and thus shows that it is an ergodic process