Verification Plan of Basic Quantum Key Distribution Experiments by Using a Small Satellite

Abstract

Space communications by lightwave have various advantages such as smaller and lighter equipment, higher data rate, larger communication capacity, and limited risk of interference with other optical communication systems. Many organizations in the world have been researching and developing the optical space communications technologies for space infrastructures to support various space activities. At the National Institute of Information and Communications Technology (NICT) in Koganei, Japan, a laser communication demonstration between the NICT optical ground station and a low earth orbit satellite was successfully conducted in 2006 to 2009. The polarization characteristics of an artificial laser source in space were measured through space-to-ground atmospheric transmission paths. Stokes parameters and the degree of polarization of the laser beam transmitted from the satellite were measured. These results contribute to the link estimation for quantum key distribution (QKD) via space and provide the potential for enhancements in QKD worldwide in the future. After this experiment, NICT has begun to develop a Small Optical TrAnsponder (SOTA) onboard a small satellite, which project is called the Space Optical Communications Research Advanced TEchnology Satellite (SOCRATES). In this mission, basic QKD experiments are planned. In this paper, the result of the field experiment between two buildings and the verification plan of basic QKD experiments is presented.