Multiple access stable frequency dissemination via fiber-optic ring network.

Area of Science:

• Optical Communications
• Network Engineering
• Metrology

Background:

• Stable frequency dissemination is crucial for modern communication networks.
• Fiber-optic ring networks face challenges with noise and single-point failures.
• Existing methods may not efficiently meet diverse user demands with limited resources.

Purpose of the Study:

• To propose a hierarchical multi-access scheme for stable frequency dissemination in fiber-optic ring networks.
• To enhance network robustness against single-node failures.
• To achieve efficient resource utilization for varying user requirements.

Main Methods:

• Implementation of a hierarchical structure with primary and secondary nodes.
• Utilizing a phase-locked loop at the primary node to suppress fiber-induced noise.
• Employing third-order mixing at secondary nodes for stable frequency output generation.

Main Results:

• Demonstrated frequency instabilities of 2.65 × 10⁻¹⁴ @ 1s and 4.58 × 10⁻¹⁷ @ 10,000s at the primary site.
• Achieved frequency instabilities of 1.48 × 10⁻¹⁴ @ 1s and 4.02 × 10⁻¹⁶ @ 10,000s at an intermediate node.
• Recorded frequency instabilities of 1.56 × 10⁻¹⁴ @ 1s and 9.70 × 10⁻¹⁶ @ 10,000s at another intermediate node.
• Validated the scheme on a 220 km fiber-optic ring network.

Conclusions:

• The proposed hierarchical multi-access scheme provides stable frequency dissemination.
• The system ensures continuous operation and fault tolerance in fiber-optic ring networks.
• This approach offers a robust foundation for stable frequency distribution in metropolitan networks.