Effect of Polarization Mode Dispersion on Pulse Propagation in Optical Fiber Links

Abstract

Polarization mode dispersion (PMD) remains one of the main sources for signal distortion in fiber optics to this day. This project focuses on studying the effects of PMD on optical signals using the Optisystem software.To investigate the impact of the different orders of PMD, we isolated the first and second order effects by manipulating specific parameters in the PMD emulator. We tried different methods to mitigate the dispersion effects associated with first order PMD. Additionally, we explored the impact of second order PMD in the presence of PCD. Lastly, we evaluated the effects of PMD in a real-world fiber environment while employing compensation techniques for both chromatic dispersion and PMD. The simulation results were analyzed using BER analyzers, oscilloscope visualizers and eye-diagrams. We have tested the PMD effects at three transmission bit rates (2.5 Gbps, 10 Gbps and 40 Gbps), while also varying different PMD emulator parameters (DGD, polarization rate, length, dispersion and attenuation). We have found that the first order PMD can cause detrimental pulse splitting of the signal, but it can be almost completely negated by either the PST or optical delay compensation method. As for second order effects, it can cause serious degradation of the signal at high bit rates, especially when paired with PCD. Finally, we have seen how CD and attenuation cause serious degradation to the signal. Using the FBG method alongside the PST method to compensate for PMD, CD and PCD gave satisfying outcomes resulting in a low BER signal and a high Quality factor .These obtained results were presented as tables, figures and graphs.