Country wide Shared FibreBased Infrastructure for Dissemination of Precise Time, Coherent Optical Frequency with Vibration Sensing

TL;DR

This paper presents a nationwide fiber-based infrastructure in the Czech Republic that provides ultra-precise time and frequency dissemination, vibration sensing, and addresses quantum communication noise challenges through wavelength separation.

Contribution

The paper introduces a shared fiber infrastructure supporting high-precision timing, frequency transfer, vibration sensing, and quantum communication with minimized interference.

Findings

Successful implementation of a shared fiber platform for multiple applications.

Effective separation of classical and quantum channels reduces noise interference.

Demonstrated capability for precise time and frequency dissemination across the country.

Abstract

With the increasing demand for ultra-precise time synchronization and frequency dissemination across various scientific, industrial, and communication fields, the Czech Republic has developed an innovative, non-commercial fiber-based infrastructure. This infrastructure serves as a shared platform, utilizing optical fibers to enable high-precision timing, coherent frequency transfer, and a newly implemented vibrational sensing capability. The project also addresses challenges posed by classical communication noise-particularly from Raman scattering-on quantum channels, especially for Quantum Key Distribution (QKD). By strategically separating classical and quantum channels into distinct wavelength bands, such as the C-band and O-band, the infrastructure achieves minimal interference while enabling multiple concurrent applications over shared fiber lines.