Document Type : Original Article
Military Technical College, Department of Communication Engineering, Cairo, Egypt.
Ministry of Defence, Cairo, Egypt.
An ideal QKD implementation that provides the promising unconditional security using single photon laser source is not practically easy, also sending these photons over a fiber channel affects the maximum distance of link up to few hundreds of kilometers because of the receiver’s detectors losses. Therefore, the achievement of a global quantum network is not easy, and the need to use LEO satellites [1,2] for establishing quantum links makes the job easier as quantum free space link provides much less losses to the link than fiber links. Nowadays, a quantum communication link can be established by satellites through free space. in this paper, we propose an implementation  of a satellite-based quantum key distribution using decoy-state protocol , we then compare this protocol with the BB-84 protocol  against security and the key length of the generated shared key.