Distributed loss and mode coupling and their effect on time-dependent propagation in multimode fibers

Area of Science:

• Optical Engineering
• Photonics
• Fiber Optics

Background:

• Accurate modeling of pulse propagation in multimode fibers is crucial for optical communication systems.
• Existing models may not fully capture complex phenomena like scattering losses and mode coupling.
• Near-field measurements offer a way to characterize fiber-specific properties.

Purpose of the Study:

• To develop a first-order solution for the transport equation to describe pulse propagation in multimode fibers.
• To incorporate models for Rayleigh-scattering-induced losses, mode coupling, and modal group velocity.
• To validate the simulation's accuracy against measured pulse responses.

Main Methods:

• Utilized a first-order solution to the transport equation for total power in degenerate mode groups.
• Developed supplementary models for Rayleigh scattering, mode coupling, and modal group velocity.
• Integrated fiber-specific parameters derived from near-field measurements into pulse propagation simulations.

Main Results:

• The developed transport equation solution effectively describes pulse propagation in multimode fibers.
• Simulations incorporating scattering losses and mode coupling closely matched experimental results.
• The model's accuracy was validated through comparison with measured pulse responses of test fibers.

Conclusions:

• The proposed first-order transport equation solution provides an accurate method for simulating pulse propagation in multimode fibers.
• The inclusion of fiber-specific models for losses and mode coupling enhances simulation fidelity.
• This approach offers a valuable tool for predicting and optimizing optical fiber performance.