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arXiv · 2505.10314

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

Josef Vojtech·Tomas Novak·Elisabeth Andriantsarazo·Vladimir Smotlacha·Ondrej Havlis·Rudolf Vohnout·Michal Spacek·Martin Slapak·Lada Altmannova·Radek Velc·Petr Pospisil·Jan Kundrat·Martin Cizek·Jan Hrabina·Simon Rerucha·Lenka Pravdova·Josef Lazar·Ondrej Cip·Jaroslav Roztocil
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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.

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Josef Vojtech, Tomas Novak, Elisabeth Andriantsarazo, Vladimir Smotlacha, Ondrej Havlis, Rudolf Vohnout, Michal Spacek, Martin Slapak, Lada Altmannova, Radek Velc, Petr Pospisil, Jan Kundrat, Martin Cizek, Jan Hrabina, Simon Rerucha, Lenka Pravdova, Josef Lazar, Ondrej Cip, Jaroslav Roztocil. 2025-05-15. Country wide Shared FibreBased Infrastructure for Dissemination of Precise Time, Coherent Optical Frequency with Vibration Sensing. https://doi.org/10.1117/12.3056668

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