An improved multidimensional reconciliation algorithm for continuous-variable quantum key distribution

Reconciliation is a crucial procedure for continuous-variable quantum key distribution (CV-QKD) systems since it directly affects the performance of practical system including processing speed, secret key rate, and maximal transmission distance. In this paper, we proposed a novel initial decoding message computation method for multidimensional reconciliation with low density parity check code, which does not need the norm information from the encoder. Both theoretical analysis and simulation results demonstrate that the improved scheme can greatly decrease the communication traffic and storage resource consumption of the reconciliation procedure almost without degradation in the reconciliation efficiency. What is more, the improved scheme can decrease the secure key consumption for classical channel authentication, then increase the secure key rate, and also be conducive to the realization of high-speed CV-QKD systems.