Combined effects of polarization mode dispersion and polarization dependent losses in optical fibers

A general description of the effects of combined polarization mode dispersion (PMD) and polarization dependent losses (PDL) in single-mode optical fiber networks is presented. It generalizes the concept of principal polarization states and its associated dynamical equation to the case where PDL is significant. The dynamical equation for the PDL vector <(Gamma)over right arrow> defined as the least attenuated polarization state, is also derived. In the presence of both PMD and PDL, the two principal polarization states are not orthogonal, leading to interferences producing anomalously large pulse spreading. This may affect the transmission capacity of the optical network. Our description also shows that the global attenuation and PDL of the fiber becomes a statistical quantity, varying with the wavelength. (C) 1997 Elsevier Science B.V.