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PUBLICATIONS

Time Synchronization over a Free-Space Optical Communication Channel

Published

Author(s)

Isaac H. Khader, Laura C. Sinclair, William C. Swann, Hugo Bergeron, Nathan R. Newbury, Jean-Daniel Deschenes

Abstract

Free space optical (FSO) communication channels are typically used to transmit high-speed data between sites over the air. Here we repurpose an FSO digital communication system and use it directly for two-way time transfer. We demonstrate real-time synchronization between two sites over a turbulent air path of 4 km using binary phase modulated CW laser light. Under synchronization, the two sites exhibit a fractional frequency deviation below 10u^-15 and a time deviation below 1 picosecond at one-hour averaging time. Over an 8-hour period the peak to peak wander is 16 ps.
Citation
Optica
Pub Type
Journals

Download Paper

DOI Link

Keywords

Optical communications, Metrology
Time and frequency metrology, Physics and Time and frequency

Citation

Khader, I. , Sinclair, L. , Swann, W. , Bergeron, H. , Newbury, N. and Deschenes, J. (2018), Time Synchronization over a Free-Space Optical Communication Channel, Optica, [online], https://doi.org/10.1364/OPTICA.5.001542 (Accessed October 24, 2025)

Issues

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Created December 20, 2018, Updated September 4, 2019
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