Exact PDL-induced SNR statistics in dual-polarization coherent optical communication systems

Area of Science:

• Optical communications engineering
• Signal processing
• Statistical modeling

Background:

• Polarization dependent loss (PDL) significantly impacts signal quality in coherent optical systems.
• Accurate modeling of PDL-induced SNR impairment is crucial for network performance.
• Existing models may not fully capture the statistical variations in complex optical networks.

Purpose of the Study:

• To derive the exact probability density function (PDF) of SNR impairment caused by PDL.
• To develop a robust analytical model for PDL statistics using the hinge model.
• To provide a tool for statistical margin assessment and quality of transmission estimation.

Main Methods:

• Utilized a sequence of variable transformations for deriving the SNR PDF.
• Employed the hinge model to represent PDL statistics.
• Validated the analytical formulation using Monte Carlo simulations.

Main Results:

• Derived the exact SNR PDF expression through nested recursive integrals.
• Demonstrated excellent agreement between the analytical model and simulations.
• Showcased the model's accuracy in capturing SNR variability from cascaded PDL elements.

Conclusions:

• The derived SNR PDF provides an accurate foundation for understanding PDL effects.
• The model supports statistical margin assessment and digital twin applications.
• Enables enhanced quality of transmission estimation in modern optical networks.