Frequency and time transfer for metrology and beyond using telecommunication network fibres

TL;DR

This paper reviews how telecommunication network fibers can be used to distribute ultra-stable optical frequency and time signals, surpassing traditional satellite methods and enabling large-scale metrological networks.

Contribution

It demonstrates that existing internet fibers can be utilized for ultra-stable frequency and time transfer, opening new possibilities for large-scale metrological applications.

Findings

Optical fiber links outperform satellite methods in stability and accuracy.

Public telecommunication networks can carry ultra-stable metrological signals.

Potential for deploying nationwide and continental optical metrology networks.

Abstract

The distribution and the comparison of an ultra-stable optical frequency and accurate time using optical fibres have been greatly improved in the last ten years. The frequency stability and accuracy of optical links surpass well-established methods using the global navigation satellite system and geostationary satellites. In this paper, we present a review of the methods and the results obtained. We show that public telecommunication network carrying Internet data can be used to compare and distribute ultra-stable metrological signals over long distances. This novel technique paves the way for the deployment of a national and continental ultra-stable metrological optical network.