A rate-adaptive data coordination method for continuous variable quantum key distribution

Abstract

The present invention provides a method for code rate adaptive data coordination in continuous variable quantum key distribution. The implementation steps of the method are as follows: the step 1: calculating a channel capacity, and calculating a code rate of an error correction code check matrix according to estimation of a signal to noise ratio of a time-varying channel through parameter estimation; the step 2: employing the punctured and shortened algorithms to respectively calculate the number of punctured bits and the number of shortened bits through Alice according to an original check matrix and an optimal check matrix code rate obtained in the step 1, generating a set of random numbers to calibrate positions of the punctured bits and the shortened bits and sending the positions ofthe punctured bits and the shortened bits to a Bob; and the step 3: employing a new check matrix to perform coding and decoding through the Alice and the Bob. Actual channel data change rapidly, and we cannot have a check matrix that applies to all the data. The method provided by the invention can flexibly adjust a code rate with change of a channel state of a time-varying channel, and can adaptthe channels with different signal-to-noise ratios, thereby improving the coordination efficiency and improving a safety bit rate of the system.

Description

technical field [0001] The invention relates to the field of code rate adaptive LDPC codes, in particular to a code rate adaptive data coordination method in the post-processing of continuous variable quantum key distribution, especially suitable for time-varying channels, which can flexibly adjust the LDPC codes as channel parameters change Code rate, improve coordination efficiency, ensure error correction performance, thereby improving the security code rate of the system. Background technique [0002] The rapid development of information technology makes people pay more and more attention to information security. With the development of technology, the existing cryptographic system has been severely challenged. Quantum Key Distribution (QKD) technology based on the principle of quantum mechanics is favored by people, and its absolute security guarantees information security. Continuous Variable Quantum Key Distribution (CV-QKD) has great advantages over Discrete Variab...

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Problems solved by technology

[0007] The purpose of the present invention is to solve the problem that the code rate needs to be flexible and variable in a time-varying channel, and propose a code rate adaptive data coordination method for continuous variable quantum key distribution to ensure that the multilateral type LDPC Code error correction performance

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