Effects of polarization dependent loss and polarization mode dispersion in recirculating loops

This study demonstrates detailed experiments and modeling on the effects of polarization dependent loss (PDL) and polarization mode dispersion (PMD) in recirculating loops. Experimental results and modeling show that the Q distribution is affected by noise which is partially polarized due to the PDL. Due to polarization dependence of the gain (PDG) in erbium doped finer amplifiers (EDFA), single channel experiments require input scrambling to eliminate this effect. Due to gain saturation in an EDFA chain the input scrambling rate can be chosen to eliminate unwanted amplitude modulation.