A Framework for Evaluating the System Penalty From Polarization-Mode Dispersion Using Different Performance Monitoring Techniques

We present a theoretical framework relating system penalties from polarization-mode dispersion (PMD) to various monitoring techniques for non-return-to-zero systems. The framework includes models for string length, radio-frequency spectral power, eye opening, and degree of polarization. We validate the models experimentally and show that they are interrelated by common constants specific to the system under investigation. We also investigate the robustness of the four PMD monitoring signals to additional optical impairments. The impairments include optical noise, chromatic dispersion, polarization-dependent loss, and self-phase modulation. We conclude that, of the monitoring techniques investigated in this paper, string length is the most robust to optical impairments.