On the role of optical fibers as channel decorrelators in system experiments

We show that the use of optical fiber as a decorrelator servers another, and as far as we know, unnoticed purpose, namely: to prevent spectral shaping of synchronized channels unlikely to be encountered in real transmission situations. In order to show the effect of the decorrelating fiber in a transmission system we study a 9 channels x 10 Gb/s WDM system over 50 km of non zero-dispersion shifted fiber