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arXiv:2507.13745 · National Science Review

Time–frequency transfer over optical fiber

Ziyang Chen, Yufei Zhang, Bin Luo, Hong Mei Guo

Published Jun 5, 2025• 20 citations
arXivHTMLPDF

Abstract

Optical time-frequency transfer establishes the metrological linkage in large-scale clock networks, which facilitates various applications. Fiber-based transfer benefits from the abundant deployment of fiber infrastructures to achieve this advantage. In this review, we provide an overview of the advances in optical two-way time-frequency transfer, which began with characterizing the time-frequency transfer stability. Then, we discuss the system configuration, key modules, main challenges and mainstream transfer methods. Finally, the review concludes with an outlook on further applications toward global-scale high-precision clock networks.

DOI
10.1093/nsr/nwaf236

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Optical time-frequency transfer establishes the metrological linkage in large-scale clock networks, which facilitates various applications. Fiber-based transfer benefits from the abundant deployment of fiber infrastructures to achieve this advantage. In this review, we provide an overview of the advances in optical two-way time-frequency transfer, which began with characterizing the time-frequency transfer stability. Then, we discuss the system configuration, key modules, main challenges and mainstream transfer methods. Finally, the review concludes with an outlook on further applications toward global-scale high-precision clock networks.
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