Polarization-Dependent Loss-Induced Outage Probabilities in Optical Communication Systems

Polarization-dependent loss (PDL)-induced outage probabilities (OPs) in optical communication systems are investigated using a semi-analytical method, taking into account the different statistics of the noise parallel and orthogonal to the signal. We show that in today's optical communication systems that typically operate at low optical signal-to-noise ratio due to the use of forward-error-correction coding, neglecting the orthogonal noise or the different statistics between the orthogonal and parallel noise significantly underestimates or overestimates PDL impairments. We find that PDL impairments are larger at lower optical signal-to-noise ratio. Required system margins at an OP of 10^-5 for given PDL values are calculated.