Encoding-based continuous variable quantum key distribution method and system

Abstract

The invention provides an encoding-based continuous variable quantum key distribution method and system. According to the method and system, a transmitting end performs coherent state preparation, andencodes a coherent state according to a continuous variable true random number of Gaussian distribution; encoded coherent state signals are transmitted to a receiving end through a quantum channel, so that the receiving end performs coherent state detection; the receiving end randomly and selectively publicizes a detection result of a part of a position and a measurement base, so that the transmitting end can perform base comparison and the data evaluation, the method restarts when a key rate is smaller than or equal to zero; the receiving end publicizes the detection result of the remainingposition, and the transmitting end judges a measurement base adopted by the receiving end according to the detection result of the remaining position; the receiving end and the transmitting end adoptcorresponding base information as their respective keys; and the receiving end and the transmitting end negotiate with each other and perform privacy amplification enhancement operation by means of aclassical channel. With the method and system of the invention adopted, long-distance secure communication under a high over-noise condition can be realized, and a requirement for negotiation efficiency is lower. Except a decoding step, all steps are consistent with an existing continuous variable quantum key distribution protocol, and therefore, the fused application of the method and the continuous variable quantum key distribution protocol can be implemented with easiness.

Description

technical field [0001] The present invention relates to the technical field of quantum communication, in particular to a continuous variable quantum key distribution method and system based on base coding. Background technique [0002] The security of quantum secure communication comes from the basic characteristics of quantum physics, which is guaranteed by Heisenberg’s uncertainty theorem and the non-cloning principle, which makes quantum secure communication have two basic characteristics, namely unconditional security of communication and protection against eavesdropping. Detectability, and these two features are almost impossible to achieve in classical communication. Therefore, in terms of information protection and secure communication, quantum secure communication has inherent advantages. [0003] Quantum key distribution technology is generally divided into two categories: discrete variable quantum key distribution (DVQKD) and continuous variable quantum key distri...

AI Technical Summary

Problems solved by technology

In addition, there are many schemes, including efficient negotiation algorithms for CVQKD, local local oscillator and other schemes, which can improve the performance of the existing CVQKD protocol to a certain extent, but they are essentially based on continuous value coding schemes. Sensitivity to over-noise and negotiation efficiency fundamentally limits its performance

In fact, in practical applications, high channel over-noise is very common, and when considering the frame error rate problem of post-processing actual negotiation, the negotiation efficiency will further affect the secure key rate of CVQKD

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