Ground to satellite secure key exchange using quantum cryptography

Abstract

Abstract. We examine the possibility of secure key exchange between a ground station and a low earth orbit satellite using the technique of quantum cryptography. The study suggests there are no technical obstacles to building a system that could exchange keys at kilobaud rates between a metre diameter telescope on the ground and a satellite with a 10 cm diameter lightweight telescope.

Complete experimental toolbox for alignment-free quantum communication

“…Finally, our scheme should find applications in the forthcoming experiments on long-distance satellite-based QC [3][4][5][6] . There, apart from misalignments, other issues may impose serious obstacles too, such as precise satellite laser-tracking, collection efficiencies, or finite-size effects (for QKD).…”

“…This is due to the fact that photons, known as so-called 'flying qubits' , are easy to transport from one location to another 1 . Photonic free-space QC has been demonstrated for distances of hundreds of kilometers 2 , a progress that could soon lead to satellite-based long-distance QC [3][4][5][6] . However, standard approaches to QC, for example, the one based on encoding qubits into the polarization of photons, require that all users involved have knowledge of a shared reference frame.…”

Air to ground quantum key distribution

“…This will enforce larger effective transmitter apertures in the regime of 10 cm [116] and even better pointing accuracy. However, in this demonstration, a major challenge was to decouple the optical system, both passively using shock mounts and actively with the FPA, from the vibrating body of the aircraft, which is not necessary to that extent on board a satellite.…”

Quantum Key Management

“…Hughes et al (2002) described experiments over a distance of 10 km at daylight and at night, and Kurtsiefer et al (2002) demonstrated the possibility of globally spanning networks. Studies regarding QKD between a terrestrial station and an orbit satellite have been conducted by Rarity et al (2002) and Pfennigbauer & Leeb (2003). Experimental implementations covering a distance of about 144 km have been reported by Schmitt-Manderbach et al (2007).…”