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arXiv · 1510.07728

Design of Raptor Codes in the Low SNR Regime with Applications in Quantum Key Distribution

Mahyar Shirvanimoghaddam·Sarah J. Johnson·Andrew M. Lance
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Abstract

The focus of this work is on the design of Raptor codes for continuous variable Quantum key distribution (CV-QKD) systems. We design a highly efficient Raptor code for very low signal to noise ratios (SNRs), which enables CV-QKD systems to operate over long distances with a significantly higher secret key rate compared to conventional fixed rate codes. The degree distribution design of Raptor codes in the low SNR regime is formulated as a linear program, where a set of optimized degree distributions are also obtained through linear programming. Simulation results show that the designed code achieves efficiencies higher than 94\% for SNRs as low as -20 dB and -30 dB. We further propose a new error reconciliation protocol for CV-QKD systems by using Raptor codes and show that it can achieve higher secret key rates over long distances compared to existing protocols.

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Mahyar Shirvanimoghaddam, Sarah J. Johnson, Andrew M. Lance. 2015-10-27. Design of Raptor Codes in the Low SNR Regime with Applications in Quantum Key Distribution. https://doi.org/10.1109/icc.2016.7510800

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