Research On Key Technologies Of Data Processing Chip For Quantum Key Distribution

Quantum Key Distribution(QKD)is an absolutely secure key distribution technology in principle.It is a product of the combination of quantum mechanics ad cryptography,which has a broad application prospects in the field of secure communication.With its unique security advantages,QKD is expected to become the best solution for secure communication in the future.China has been working in the QKD field for many years and has been at the forefront of the world.The complete success of a series of experiments on the Micius scientific experiment satellite,and the completion of the Beijing-Shanghai trunck line of quantum quantum secure communication,signified that our country's world-integrated QKD network has been initially established.In the future,China will build a QKD network with wider coverage and better performance.The development trend of QKD is the civilianzation of technology,the globalization of networking,and the miniaturization of equipment.The miniaturization of equipment is an important foundation for the large-scale construction and application of QKD networks,and the key to equipment miniaturization is the chipization of key components of QKD system.This paper focuses on the integration of the data processing subsystem in the QKD system,and proposes to design a QKD dedicated data processing chip(called QKD_SOC chip)based on ASIC(Application-Specific Integrated Chip,ASIC)technology to replace the data processing subsystem in the original QKD equipment.The QKD dedicated data processing chip integrates multiple functions such as laser encoding,detector control,QKD data post-processing,key distribution,network negotiation,process control,etc.It will lay an important foundation for the integration,low power consumption and low cost of QKD equipment.More importantly,this chip is China's first data processing chip for the QKD field,and we have complete independent intellectual property rights of this chip,which is of great significance for China to realize technology autonomy in the field of QKD.The goal of the design is to replace the data processing subsystem in the original QKD equipment with an ASIC chip which coordinates the lazer subsystem and the detector subsystem to realize the function of quantum key generation.Specifically,the QKD_SOC chip implements the following functions.The first is to realize the management of the laser subsystem.The chip provides driving code information for the laser subsystem to drive it to generate light pulses.In addition,the chip is required to monitor and manage the operating status of the laser subsystem.The second is to realize the management of the detector subsystem.The chip monitors and manages the operating status of the dector subsystem,and it obtains the original information of the detected photons.The third is to realize the management of the key generation process.The key generation process includes negotiation with key management equipment,calibration of QKD equipment,generation of laser coding information,acquisition and pre-processing of detector data,post-processing of QKD data,network negotiation,key upload,etc.The QKD_SOC chip adopts the "processor+coprocessor" architecture.The CPU(Central Processing Unit)is used to achieve QKD task scheduling and process management.The QKD coprocessor is used to achieve high-speed QKD data post-processing.The TOE(TCP/IP Offload Engine)is used to realize the network negotiation.The final test results show that the QKD_SOC chip has achieved the function expected by the design.Its data processing capability supports key generation at a rate of 100kbps.The innovations of this paper are mainly reflected in the following aspects.(1)The QKD_SOC chip is China's first data processing chip for QKD filed,with independent intellectual property rights.It is designed based on the existing mature QKD architecture and realizes the integration and low power consumption of the QKD system at the system level for the first time.(2)Realize the network negotiation scheme based on TOE technology.It is the first time that the TOE techonology is introduced into the field of QKD,which is of great significance for improving the speed,stability and security of QKD network negotiation.(3)Realize the coprocessor-based scheme for QKD data post-processing.The coprocessor integrates all data post-processing algorithms required by QKD,including basis vector comparison,information fusion,error key correction,privacy amplification,etc.It is of great significance for improving the speed and security of key processing.