Quantum cryptography distributing polarization feedback system and implementation method thereof

Abstract

The invention relates to an implementation method of a quantum cryptography distributing polarization feedback system comprising the steps of: a signal generated by a laser entering a polarization controller and a detector through a channel optical fiber in order, when the signal enters the detector, the detector beginning to count; when a system error rate is bigger than a pre-setting value, a polarization feedback module working; the laser sending out special polarized light, the polarization feedback module sending out a polarization feedback signal to the polarization controller, and the polarization controller adjusting the output signal according to the voltage variation. The implementation method also comprises the following steps of: initiating a polarization feedback by a receiver, transmitting orders through reliable connection of a sender and the receiver, controlling the sender to send polarized lights, and adjusting the polarization to the required state by the receiver through controlling the polarization controller of a corresponding HV / +- basis vector. The polarization feedback module controls the laser of the sender to emit light in different polarization directions according to needs, feeds the light back at the receiver and compensates the influences brought by the disturbance of the channel optical fiber.

Description

technical field [0001] The invention relates to the field of quantum secure communication, in particular to a quantum cryptography distribution polarization feedback system and an implementation method thereof. Background technique [0002] The polarization feedback algorithm works in the polarization-encoded quantum cryptography distribution scheme. Since the optical fiber between the sender and receiver may be disturbed by factors such as the environment, the polarization of the optical signal will change, which will increase the error rate of the receiver. In order to keep the error rate low, polarization feedback is required in the polarization-encoded quantum key distribution system. [0003] In the quantum cryptography distribution system, when the H and V light emitted by the sender are detected under the HV base vector, H and V results should be obtained respectively, and when there is no attack between the sender and the receiver, if the detection result of the H li...

AI Technical Summary

Problems solved by technology

[0002] The polarization feedback algorithm works in the polarization-encoded quantum cryptography distribution scheme. Since the optical fiber between the sender and the receiver may be disturbed by factors such as the environment, the polarization of the optical signal will change, which will increase the error rate of the receiver.

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