A new scheme for quantum key distribution in free-space

Quantum key distribution (QKD) has been proposed for decades. Many applications have been deployed recently for both wired and wireless networks. Especially for optical networks, QKD technique has a great development. But in free-space quantum key distribution still has a lot of problems such as a low bit rate. In this paper we propose a new scheme, combining MIMO (Multiple input multiple output) system and wireless networks for QKD in free-space networks. With the proposed approach, a higher bit rate QKD networks in free-space could be realized theoretically.