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A DPTD frequency standard comparison system
1Department of Measurement and Instrumentation, Xidian University, Xi’an, China. wanghai@mail.xidian.edu.cn
IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
|November 30, 2012
Summary
A new dual phase-coincidence-detection time difference (DPTD) system offers high-resolution frequency standard comparison. This cost-effective instrument achieves better than 10 ps resolution, simplifying complex measurements.
Area of Science:
- Metrology
- Precision Measurement
- Time and Frequency Standards
Background:
- Accurate comparison of frequency standards is crucial for scientific and technological advancements.
- Existing methods for time difference measurement can be complex and costly.
Purpose of the Study:
- To propose a novel dual phase-coincidence-detection time difference (DPTD) system for frequency standard comparison.
- To demonstrate a simple, low-cost instrument with high resolution for phase comparison.
Main Methods:
- Utilizing the greatest common factor frequency concept and a high-stability common frequency source.
- Implementing phase coincidence detection for high-resolution phase comparison between frequency standards.
- Developing a simple instrument with a resolution better than 10 picoseconds (ps).
Main Results:
- The proposed DPTD system achieves a resolution better than 10 ps.
- Theoretical analysis indicates a resolution significantly higher than 10 ps.
- The system offers a simpler structure and lower cost compared to dual-mixer time difference systems.
Conclusions:
- The DPTD system provides a simple and cost-effective solution for high-resolution frequency standard comparison.
- This method enhances the feasibility of precise time and frequency measurements.
- The developed instrument is suitable for applications requiring accurate phase comparison.
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