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arXiv · 0903.2160

Feasibility of satellite quantum key distribution

Cristian Bonato·Andrea Tomaello·Vania Da Deppo·Giampiero Naletto·Paolo Villoresi
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Abstract

In this paper we present a novel analysis of the feasibility of quantum key distribution between a LEO satellite and a ground station. First of all, we study signal propagation through a turbulent atmosphere for uplinks and downlinks, discussing the contribution of beam spreading and beam wandering. Then we introduce a model for the background noise of the channel during night-time and day-time, calculating the signal-to-noise ratio for different configurations. We also discuss the expected error-rate due to imperfect polarization-compensation in the channel. Finally, we calculate the expected key generation rate of a secure key for different configurations (uplink, downlink) and for different protocols (BB84 with and without decoy states, entanglement-based Ekert91 protocol).

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Cristian Bonato, Andrea Tomaello, Vania Da Deppo, Giampiero Naletto, Paolo Villoresi. 2009-05-12. Feasibility of satellite quantum key distribution. https://doi.org/10.1088/1367-2630%2F11%2F4%2F045017

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