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Published on: September 5, 2019
Polarization fluctuation in optical fibers based on probability.
Optics Letters
|September 11, 2009
Summary
Polarization fluctuations in long optical fibers were measured and analyzed using the Poincaré sphere. A novel polarization controller was developed to automatically compensate for these fluctuations, ensuring signal stability.
Area of Science:
- Optical engineering
- Telecommunications
- Fiber optics
Background:
- Polarization fluctuations in optical fibers can degrade signal quality over long distances.
- Understanding these fluctuations is crucial for maintaining reliable optical communication systems.
- Existing methods for managing polarization may be insufficient for dynamic, long-haul fiber environments.
Purpose of the Study:
- To quantify polarization fluctuations in various deployed fiber optic cables, including submarine and underground.
- To analyze the statistical behavior of polarization state changes on the Poincaré sphere.
- To develop and implement an automated system for compensating polarization fluctuations.
Main Methods:
- Measurements of polarization fluctuations were conducted in submarine, underground, and long-haul fiber optic cables up to 270 km.
- The Poincaré sphere model was utilized to analyze the probability distributions of polarization states.
- An endlessly rotatable polarization controller was employed for real-time compensation.
Main Results:
- Polarization fluctuations were successfully measured across diverse fiber optic installations.
- For small fluctuations, the polarization state distribution on the Poincaré sphere approximated a 2D normal distribution.
- The implemented polarization controller effectively compensated for observed fluctuations.
Conclusions:
- Polarization fluctuations in deployed fiber optic systems exhibit predictable statistical properties.
- Automated compensation using an endlessly rotatable controller is a viable solution for maintaining signal integrity.
- This work contributes to the advancement of stable long-haul optical communication.
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