摘要 |
PROBLEM TO BE SOLVED: To make signals be synchronized between a transmitter and a receiver when a relative position between the transmitter and the receiver performing quantum cryptographic communication changes. SOLUTION: A satellite which is a transmitter 101 is positioned over a ground station A (102A) at time T1, generates a quantum key α, and transmits the quantum key α superposed on data A to the ground station A by using laser light. The transmitter 101 is moved to over a ground station B (102B) at time T2, generates a quantum key β, and transmits the quantum key β superposed on data B to the ground station B by using the laser light. The transmitter 101 generates a third quantum key γ by exclusive OR between the quantum key α and the quantum key β, and transmits the third quantum key γ to the ground station A and the ground station B by using normal communication means. The ground station A generates the quantum key β by exclusive OR between the quantum key α retained by the own station and the third quantum key γ. The ground station B generates the quantum key α by exclusive OR between the quantum key β retained by the own station and the third quantum key γ. COPYRIGHT: (C)2012,JPO&INPIT |