Optical Ground Station Diversity for Satellite Quantum Key Distribution in Ireland

TL;DR

This study evaluates the feasibility of satellite quantum key distribution in Ireland by analyzing weather effects on optical ground stations, demonstrating that a multi-station network can significantly enhance service availability despite cloud cover challenges.

Contribution

It presents the first assessment of Ireland's geographic and weather impacts on satellite quantum communication and proposes a multi-OGS approach to improve system reliability.

Findings

A 4-OGS network can improve performance by up to 45%.

Cloud cover variability can be mitigated with multiple ground stations.

Most performance gains are achieved with 2 or 3 OGSs.

Abstract

Space quantum communications is a potential means for establishing global secure communications and quantum networking. Despite pioneering demonstrations of satellite quantum key distribution, considerable challenges remain for wide deployment such as the local effects of the atmosphere on the transmission of single-photon level quantum signals. As part of Ireland's efforts to establish quantum links with the rest of Europe and further afield, we present a preliminary study of the feasibility of satellite quantum key distribution taking into account geographic and weather effects on the space-Earth channel. Weather data over 5 years covering 4 locations across Ireland were used to assess performance and the prospects of optical ground station (OGS) geographic diversity to improve service availability. Despite significant cloud cover that may reduce the performance of a single OGS location, the use of a 4-OGS network can provide up to 45% improvement for a single satellite exploiting anti-correlation in cloud cover, though most gains are achieved with 2 or 3 OGSs.