The Research And Implementation Of Spaceborne Real-time Quantum Communication Software Based On VxWorks

Quantum communication based on the basic theory of quantum mechanics,to achieve absolute security of confidential communications.With the help of the satellite platform,the experiment of the high-speed satellite quantum key distribution is carried out to find the application of quantum theory in macro scale and promote the final realization of quantum communication in the wide area and even worldwide.By optimizing the various components of the quantum key distribution system can greatly improve the key into the code rate,accelerate the practical development of quantum secure communication process.This topic aims to realize the high-speed quantum key distribution and the real-time key extraction.The whole system is designed with embedded processor PowerPC MPC8641 D and FPGA XCKU040 architecture,through the VxWorks multi-task mode of the embedded real-time operating system,achieving the key distribution data for real-time processing to extract the security key.Designing high-speed data channel,which is based on PCIE1.0 bus protocol,using FPGA built-in PCIE IP hard core and achieving FPGA XCKU040 through the GTH interface and MPC8641 D high-speed serial-to-parallel converter to PCIE X8 mode connection.Try to develop the VxWorks driver framework VxBus under the PCIE driver,DMA can read up to 176MB/s and write up to 221MB/s through the DMA test data transfer speed.Real-time key extract the software mainly through the quantum communication algorithm,the base vector comparison,key error correction and the privacy amplification process from the original data to extract the absolute security key.In accordance with the modular thinking,the quantum communication algorithm is divided into seven tasks.Tasks between the use of VxWorks cycle allocation and complete preemptive task scheduling is in the wind kernel scheduling under the real data on the "parallel" processing.The algorithm of random replacement key is designed with the calculation of checksum task and to ensure the randomness in the process of key error correction.The algorithm of abandoning and the discarding algorithm in the task of discarding information can greatly improve the speed of operation.The amplification task can introduce the data compression method of the key string multiplied by the Toeplitz matrix,reduce the generation and storage load of the random number,and finally realize the real-time extraction of the security key.According to the test,we can ensure that the system is stable.It can also meet the real-time extraction of the purpose of security keys.So,the result is that the program is feasible.