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Modal-noise generation in biconical-taper couplers
Optics Letters
|August 28, 2009
Summary
Modal noise in fused biconical-taper couplers is measured and explained. Even with many ports, modal noise is not severe and unlikely to degrade digital fiber system performance.
Area of Science:
- Optical Engineering
- Telecommunications
Background:
- Modal noise arises from the division of coherent light in optical fiber couplers.
- Fused biconical-taper (FBT) star and access couplers are common components in fiber optic systems.
Purpose of the Study:
- To measure and theoretically explain modal noise in FBT star and access couplers.
- To assess the impact of modal noise on digital fiber system performance.
Main Methods:
- Experimental measurement of modal noise levels.
- Theoretical modeling and explanation of noise generation mechanisms.
Main Results:
- Modal noise generation was quantified in FBT couplers.
- Noise levels were found to be not severe, even in couplers with a high number of ports.
- Strong subdivision of light did not lead to significant modal noise.
Conclusions:
- Modal noise in FBT couplers is generally not a critical issue.
- The performance of most digital fiber systems is not expected to be significantly affected by the measured modal noise levels.
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