A New Quantum Key Distribution Scheme Based on Frequency and Time Coding

• Published in: Chinese physics letters Vol. 27; no. 9; pp. 12 - 15
• Main Author: 朱畅华 裴昌幸 权东晓 高晶亮 陈南 易运晖
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.09.2010
• Subjects: Amplification; Channels; Coding; Computer information security; Optical pulses; Photons; Receivers; Time delay; 二进制编码; 光脉冲; 密钥分配方案; 时间延迟; 时间编码; 量子密码系统; 随机测量; 频率设置
• ISSN: 0256-307X; 1741-3540
• DOI: 10.1088/0256-307X/27/9/090301

A new scheme of quantum key distribution （QKD） using frequency and time coding is proposed, in which the security is based on the frequency-time uncertainty relation. In this scheme, the binary information sequence is encoded randomly on either the centrM frequency or the time delay of the optical pulse at the sender. The central frequency of the single photon pulse is set as w1 for bit 0 and set as w2 for bit 1 when frequency coding is selected. However, the single photon pulse is not delayed for bit 0 and is delayed in τ for 1 when time coding is selected. At the receiver, either the frequency or the time delay of the pulse is measured randomly, and the final key is obtained after basis comparison, data reconciliation and privacy amplification. With the proposed method, the effect of the noise in the fiber channel and environment on the QKD system can be reduced effectively.