Study of LEO satellite constellation systems based on quantum communications networks

Quantum cryptography, or more specifically quantum key distribution (QKD), is the first offspring of quantum information that has reached the stage of real-world application. Its security is based on the fact that a possible spy (Eve, the eavesdropper) cannot obtain information about the bits that Alice sends to Bob, without introducing perturbations. Therefore authorized partners can detect the spy by estimating the amount of error in their lists. The central objective of this paper is to implement and improve practical systems for quantum cryptography. The essential work carried in our research laboratory concerns the software development to implement of Quantum Key Distribution (QKD) Network based on LEO orbit number and reduce the telecommunication interruption risks and this will provide indeed a better communication quality, and investigations into the causes of losses in the system and attempts to minimize the quantum bit error rate (QBER).