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arXiv · 1505.06423

Simple rate-adaptive LDPC coding for quantum key distribution

Mo Li·Chun-Mei Zhang·Zhen-Qiang Yin·Wei Chen·Chuan Wang·Zheng-Fu Han
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Abstract

Although quantum key distribution (QKD) comes from the development of quantum theory, the implementation of a practical QKD system does involve a lot of classical process, such as key reconciliation and privacy amplification, which is called post-processing. Post-processing has been a crucial element to high speed QKD systems, even the bottleneck of it because of its relatively high time consumption. Low density parity check (LDPC) is now becoming a promising approach of overcoming the bottleneck due to its good performance in processing throughput. In this article we propose and simulate an easily implemented but efficiently rate-adaptive LDPC coding approach of reconciliation, different from the previously proposed puncturing- and shortening-based approach. We also give a measure for choosing the optimal LDPC parameter for our rate-adaptive approach according to error rates.

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Mo Li, Chun-Mei Zhang, Zhen-Qiang Yin, Wei Chen, Chuan Wang, Zheng-Fu Han. 2015-05-24. Simple rate-adaptive LDPC coding for quantum key distribution. https://arxiv.org/abs/1505.06423

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