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arXiv · 2212.11537

Performance analysis for OFDM-based multi-carrier continuous-variable quantum key distribution with arbitrary modulation protocol

Heng Wang·Yan Pan·Yun Shao·Yaodi Pi·Ting Ye·Yang Li·Tao Zhang·Jinlu Liu·Jie Yang·Li Ma·Wei Huang·Bingjie Xu
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Abstract

Multi-carrier continuous-variable quantum key distribution (CV-QKD) is considered to be a promising way to boost the secret key rate (SKR) over the existing single-carrier CV-QKD scheme. However, the extra excess noise induced in the imperfect multi-carrier quantum state preparation process of N subcarriers will limit the performance of the system. Here, a systematic modulation noise model is proposed for the multi-carrier CV-QKD based on the orthogonal frequency division multiplexing (OFDM). Subsequently, the performance of multi-carrier CV-QKD with arbitrary modulation protocol (e.g. QPSK, 256QAM and Gaussian modulation protocol) can be quantitatively evaluated by combining the security analysis method of the single-carrier CV-QKD. Under practical system parameters, the simulation results show that the SKR of the multi-carrier CV-QKD can still be significantly improved by increasing the carrier number N even with imperfect practical modulations. Specifically, the total SKR of multi-carrier CV-QKD can be optimized by carefully choosing N. The proposed model provides a feasible theoretical framework for the future multi-carrier CV-QKD experimental implementation.

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Heng Wang, Yan Pan, Yun Shao, Yaodi Pi, Ting Ye, Yang Li, Tao Zhang, Jinlu Liu, Jie Yang, Li Ma, Wei Huang, Bingjie Xu. 2022-12-22. Performance analysis for OFDM-based multi-carrier continuous-variable quantum key distribution with arbitrary modulation protocol. https://doi.org/10.1364/oe.482136

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