Fang Junbin, Yi Zhengzhong, Li Jin, Liang Zhipeng, Wu Yulin, Lei Wen, Jiang Zoe Lin, Wang Xuan
Department of Optoelectronic Engineering, Jinan University, Guangzhou, 510632, China.
Cyberspace Security Research Center, Peng Cheng Laboratory, Shenzhen, 518055, China.
Sci Rep. 2022 Jun 16;12(1):10155. doi: 10.1038/s41598-022-14145-6.
Combined with one-time pad encryption scheme, quantum key distribution guarantees the unconditional security of communication in theory. However, error correction and privacy amplification in the post-processing phase of quantum key distribution result in high time delay, which limits the final secret key generation rate and the practicability of quantum key distribution systems. To alleviate this limitation, this paper proposes an efficient post-processing algorithm based on polar codes for quantum key distribution. In this algorithm, by analyzing the channel capacity of the main channel and the wiretap channel respectively under the Wyner's wiretap channel model, we design a codeword structure of polar codes, so that the error correction and privacy amplification could be completed synchronously in a single step. Through combining error correction and privacy amplification into one single step, this efficient post-processing algorithm reduces complexity of the system and lower the post-processing delay. Besides, the reliable and secure communicaiton conditions for this algorithm has been given in this paper. Simulation results show that this post-processing algorithm satisfies the reliable and secure communication conditions well.
量子密钥分发与一次性密码本加密方案相结合，在理论上保证了通信的无条件安全性。然而，量子密钥分发后处理阶段的纠错和隐私放大导致了高时延，这限制了最终的秘密密钥生成速率和量子密钥分发系统的实用性。为了缓解这一限制，本文提出了一种基于极化码的量子密钥分发高效后处理算法。在该算法中，通过在Wyner窃听信道模型下分别分析主信道和窃听信道的信道容量，设计了极化码的码字结构，使得纠错和隐私放大能够在一步中同步完成。通过将纠错和隐私放大合并为一步，这种高效的后处理算法降低了系统的复杂度并减少了后处理延迟。此外，本文还给出了该算法可靠且安全的通信条件。仿真结果表明，这种后处理算法很好地满足了可靠且安全的通信条件。
