Chirp-based continuous variable quantum key distribution method and system for realizing chirp-based continuous variable quantum key distribution method

Abstract

The invention discloses a chirp-based continuous variable quantum key distribution method. The chirp-based continuous variable quantum key distribution method comprises the steps that a quantum key sending end modulates a quantum signal; the quantum key sending end sends the modulated quantum signal to a quantum key receiving end through a quantum channel; the quantum key receiving end performs coherent detection on the received quantum signal and obtains a detection result; and the detection result is post-processed to obtain a final quantum key. The invention also discloses a distribution system for realizing the chirp-based continuous variable quantum key distribution method. According to the invention, the adverse effect of the frequency chirp effect on the signal in the middle-distance transmission is eliminated, and the transmission reliability is improved; meanwhile, the method does not need to use a heterodyne modulator at a sending end, only needs to estimate the chirp coefficient at the beginning of transmission, effectively saves the cost, is high in reliability, is better in performance, is low in cost, and is convenient to implement.

Description

technical field [0001] The invention belongs to the field of quantum communication, and in particular relates to a chirp-based continuous variable quantum key distribution method and distribution system. Background technique [0002] With the development of economy and technology and the improvement of people's living standards, communication has been widely penetrated into people's production and life, bringing endless convenience to people's production and life. With the advent of the intelligent age and the data age, the security of communication data is getting more and more attention. [0003] Quantum key distribution enables legitimate communication parties to safely share keys in an untrusted quantum channel, and its security is guaranteed by the uncertainty principle of quantum mechanics and the quantum non-cloning theorem. At present, quantum key distribution is divided into two directions: discrete variable and continuous variable according to the difference of in...

AI Technical Summary

Problems solved by technology

However, the use of external modulation and coherent detection has the following disadvantages in the medium-distance transmission of 20-1000 kilometers: (1) the cost of this scheme is huge, and the cost performance of using it in the medium-distance transmission scheme is too low; (2) the volume of the external modulator is too large Large and cannot be integrated into compact transmitter optics

However, this scheme only makes symbol decisions based on light intensity at the receiving end, discarding phase information, resulting in a large gap between performance and traditional schemes

Therefore, in medium-distance transmission, there is not yet a better technical solution that takes into account both cost and performance.

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