Research On Wireless Quantum Communication Network Of Mixed State Based On Mesh Structure

Quantum communication is one of the most important applications of quantum information. Compared with the classical communication, quantum communication has many advantages, such as safety, high speed, high capacity. Quantum communication is heading for practical application and will have a profound impact on communication mode in the future.Quantum teleportation is one of the important techniques in quantum communication. Combining quantum teleportation technology with wireless network, a wireless quantum communication network model based on the structure of backbone Mesh network is proposed. Quantum information is transmitted hop by hop through quantum teleportation in this network. There exist quantum channel and classical wireless channel in this network, and the quantum channel is composed of entangled particles in the mixed state. Based on this network model, entangled particles distribution which is a specific problem in quantum realm is studied. We first illustrate the importance of connectivity in the backbone Mesh structure in the network and put forward the quantum distribution algorithm of entangled particles based on minimum spanning tree. Quantum entanglement is an important resource for quantum teleportation. The mixed state, especially in the real process of teleportation, is more practical. The situation that one kind of mixed states, Werner state, is the quantum channel is discussed. According to the design of the quantum information transmission schemes, this paper deduce specific expression of the recovered state not only after one-hop teleportation, but also across multiple intermediate nodes based on Werner state. We also obtain the fidelity of multi hop teleportation. Routing protocol is one of the important parts in the network. Based on the characteristics of wireless quantum communication network, we propose the routing metric which is the combination of hops and transmission delay. And a detailed description of the routing discovery and maintenance process in quantum communication network is discussed. Finally, the simulation and analysis of the proposed routing protocol are provided. The simulation shows that the routing protocol can reduce transmission delay while the reliability of network transmission is ensured.