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Updated: May 31, 2026
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Construction and Characterization of External Cavity Diode Lasers for Atomic Physics
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A low noise and ultra-narrow bandwidth frequency-locked loop based on the beat method
Wei Gao1, Jianping Sui, Zhiyong Chen
1Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, China.
Summary
A new digital frequency-locked loop (FLL) using the beat method offers a simple, low-noise solution. This technology effectively reduces phase noise in atomic frequency standards for ultra-low noise, cost-effective composite standards.
Area of Science:
- Electronics and Electrical Engineering
- Metrology
- Signal Processing
Background:
- Atomic frequency standards are crucial for precise timekeeping and navigation.
- Reducing close-in phase noise is essential for improving the performance of frequency standards.
- Existing frequency feedback loops can be complex and introduce significant noise.
Purpose of the Study:
- To propose a novel digital frequency-locked loop (FLL) based on the beat method.
- To demonstrate the FLL's capability in reducing close-in phase noise.
- To enable the realization of composite frequency standards with enhanced performance and reduced cost.
Main Methods:
- Implementation of a digital frequency-locked loop (FLL) utilizing the beat method.
- Experimental validation of the FLL's performance characteristics.
- Integration of the FLL with atomic frequency standards.
Main Results:
- The proposed FLL exhibits a simple digital structure.
- The FLL demonstrates very low noise performance.
- Experimental results confirm the reduction of close-in phase noise on atomic frequency standards.
Conclusions:
- The beat-method-based FLL provides a simple and low-noise digital solution.
- This FLL effectively suppresses close-in phase noise in atomic frequency standards.
- The FLL facilitates the creation of cost-effective composite frequency standards with ultra-low phase noise.
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