【作者】 李旭；

【导师】 薛玲玲；

【作者基本信息】 长春理工大学 ， 物理电子学， 2009， 硕士

【摘要】 本文首先通过当今保密通信的重要性引出了对自由空间量子密码通信的讨论,并分析了量子密码术应用于通信领域的优点,然后对其发展现状存在问题和发展前景做了讨论。之后介绍了自由空间量子密码通信的物理基础和信息学基础。最后着重对现存的自由空间量子密码通信的试验做了总结并对目前最为先进的试验方案的过滤装置和通信信道两部分提出了改进方案:取代原方案中普通滤光片,本文提出的过滤装置采用原子气过滤器,它能够更好的抑制背景光的干扰,进而提升整个系统的信噪比;通信信道应用的多入多出装置能够有效的增加信道的通信容量,并且也能够对增大整个系统的信噪比做出贡献。更多还原

【Abstract】 Discussions about quantum cryptography communication in free space are firstly put forward through advancing the topic of the importance of secret communication nowadays. Advantages of using quantum cryptography into the application of communication fields are also pointed out. Then its developing status, existing problems and developing future are analyzed one by one. Further more, the physical foundations and informational bases of free space quantum cryptography are introduced. Finally, the emphases are focused on the present quantum cryptography experiments and an improved scheme toward one of them are shown in the paper, which mainly includes rectifications of two parts of the original idea: the atomic vapor filter the paper advances could better reduce the interference of background light which help increase the signal to noise ratio; the multi-input-multi-output system mentioned in the paper in its communication channel could effectively increase the communication capacity of it, which also contributes to the improvement of its signal to noise ratio.更多还原