| Quantum cryptography communication is an interdisciplinary based on the foundation of classical communication and quantum mechanics. As the superiority of unconditional safety, it becomes a new secure communications technology, and it is given more attention because of potential value in various fields. Therefore, more and more people focus on the research of quantum key distribution.In this dissertation, we research on the implementation of the quantum cryptography communication system based on BB84 protocol, and mainly facus on the realization of quantum key distribution system with polarization encoding. Firstly, we introduce the basic principles of Quantum cryptography communication and BB84 protocol, and we propose a quantum key distribution system model under the optical fiber channels based on polarization encoding. Secondly, using the winsock network programming, the software program part of BB84 protocol is implemented based on the C/S mode between sender and receiver. Thirdly, in the theoretical study of polarization, the importance of polarization control in the quantum key distribution system is described. A kind of polarization control model of quantum key distribution system and the principle of auto-feedback operation are given. Finally, according to the data sampled from the experiment on the basis of experimental platform, the polarization auto-feedback control algorithm has been discussed. |
