@inproceedings{oai:jaxa.repo.nii.ac.jp:00013340, author = {豊嶋, 守生 and 竹中, 秀樹 and 高山, 佳久 and 國森, 裕生 and 武岡, 正裕 and 藤原, 幹生 and 佐々木, 雅英 and Toyoshima, Morio and Takenaka, Hideki and Takayama, Yoshihisa and Kunimori, Hiroo and Takeoka, Masahiro and Fujiwara, Mikio and Sasaki, Masahide}, book = {宇宙利用シンポジウム, Space Utilization Research: Proceedings of Space Utilization Symposium}, month = {Mar}, note = {第25回宇宙利用シンポジウム(2009年1月14日-15日, 宇宙航空研究開発機構宇宙科学研究本部相模原キャンパス), The Twenty-fifth Space Utilization Symposium (January 14-15, 2009: ISAS/JAXA Sagamihara, Japan), A free-space quantum key distribution system is being developed by the National Institute of Information and Communications Technology (NICT) in Koganei, Japan. Quantum cryptography is a new technique for transmitting information where the security is guaranteed by the laws of physics. In such systems, a single photon is used for the quantum information; however, since the transmission distance in optical fibers is limited by the absorption of photons by the fiber, the maximum demonstrated range has been about 100 km. Free-space quantum cryptography between an optical ground station and a satellite is a possible solution to extend the distance for a quantum network further beyond the limits of optical fibers. At NICT, a laser communication demonstration between the NICT optical ground station and a low earth orbit satellite was successfully conducted in 2006. For such space communication links, free-space quantum cryptography is considered an important application for the future. A bread board model for free-space quantum cryptography using a free-space polarization tracking scheme has been developed by NICT, and the preliminary test results for the quantum key distribution with the polarization tracking between two buildings in NICT are presented., 形態: カラー図版あり, 資料番号: AA0064297096}, publisher = {宇宙航空研究開発機構宇宙科学研究本部, Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)}, title = {空間伝送用量子暗号通信システムの地上伝送実験}, volume = {25}, year = {2009} }