arXiv:2412.14944 · EPJ Quantum Technology

Estimating the impact of light pollution on quantum communication between QEYSSat and Canadian quantum ground station sites

Mathew Yastremski, Paul J. Godin, Nouralhoda Bayat, Sungeun Oh, Ziheng Chang, Katanya B. Kuntz, Daniel Oblak, Thomas D. Jennewein

Published Feb 27, 2025• 3 citations

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Abstract

Satellite to ground quantum communication typically operates at night to reduce background signals, however it remains susceptible to noise from light pollution of the night sky. In this study we compare several methodologies for determining whether a Quantum Ground Station (QGS) site is viable for exchanging quantum signals with the upcoming Quantum Encryption and Science Satellite (QEYSSat) mission. We conducted ground site characterization studies at three locations in Canada: Waterloo, Ontario, Calgary, Alberta, and Priddis, Alberta. Using different methods we estimate the background counts expected to leak into the satellite-ground quantum channel, and determined whether the noise levels could prevent a quantum key transfer. We also investigate how satellite data recorded from the Visible Infrared Imaging Radiometer Suite (VIIRS) can help estimate conditions of a particular site, and find reasonable agreement with the locally recorded data. Our results indicate that the Waterloo, Calgary, and Priddis QGS sites should allow both quantum uplinks and downlinks with QEYSSat, despite their proximity to urban centres. Furthermore, our approach allows the use of satellite borne instrument data (VIIRS) to remotely and efficiently determine the potential of a ground site.

DOI: 10.1140/epjqt/s40507-025-00331-8

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