关键词: 量子卫星通信/
偶发E层/
自由电子密度/
振幅阻尼信道
English Abstract
Influence of the ionospheric sporadic E layer on the performance of quantum satellite communication in the mid latitude region
Nie Min1,Tang Shou-Rong1,
Yang Guang1,2,
Zhang Mei-Ling1,
Pei Chang-Xing3
1.School of Communication and Information Engineering, Xi'an University of Posts and Telecommunication, Xi'an 710121, China;
2.School of Electronics and Information, Northwestern Polytechnical University, Xi'an 710072, China;
3.State Key Laboratory of Integrated Service Networks, Xi'an University of Electronic Science and Technology, Xi'an 710071, China
Fund Project:Project supported by the National Natural Science Foundation of China (Grant Nos. 61172071, 61201194), the Natural Science Research Foundation of Shaanxi Province, China (Grant No. 2014JQ8318), the International Scientific and Technological Cooperation and Exchange Program in Shaanxi Province, China (Grant No. 2015KW-013) and Scientific Research Program Funded by Shaanxi Provincial Education Department, China (Grant No. 16JK1711).Received Date:28 October 2016
Accepted Date:30 November 2016
Published Online:05 April 2017
Abstract:Quantum communication is a brand new way of communicating, in which the quantum entanglement effect is used to transmit information. Quantum communication is a new interdisciplinary subject between quantum theory and information theory. It has advantages of perfect information security and higher efficiency in transmission. The successful launch of the first quantum satellite named Micius laid an important foundation forconstructing a secure quantum communication network on a global scale. On the other hand, in the process of quantum satellite communication, the atmospheric environment near the ground will have a certain influence on the transmission of quantum signals, so the security of quantum communication is reduced. One of the influence factors is the ionospheric sporadic E layer. In the actual quantum communication environment, when the weak coherent state light source is simulated the single photon, the source energy is attenuated if the quantum signal passes through the ionosphere. On a space scale of 80-150 km off the ground, the ionospheric sporadic E layer is an irregular thin layer, in which there occurs a sharp increase of electron density under the action of wind shear. Sporadic E layer has a great influence on quantum satellite signal transmission. However, the research about the relationship between the sporadic E layer and quantum communication channel parameters has not yet conducted. To investigate the influence of the ionospheric sporadic E layer on the performance of quantum satellite communication, sporadic E layer formation process is first analyzed. And then the relationship between the free electron density and the height is obtained. After that, the model of the free electron density, the formation thickness and the link attenuation of quantum satellite is established. According to the amplitude damping channel, the quantitative relationships among free electron density and the channel capacity, entanglement fidelity, the quantum bit error rate and the secure key rate are put forward and simulated finally. Theoretical analysis and simulation results show that when the thickness is 1 km, the electron density increases from 3105 cm-1 to 27105 cm-1, the channel capacity decreases from 0.8304 to 0.1319, the entanglement fidelity decreases from 0.9386 to 0.3606, the quantum bit error rate increases from 0.0093 to 0.0769, and the secure key production rate decreases from 9.96810-5 to 1.9110-6. It can be shown that the electron density and the thickness of sporadic E layer have significant effect on the performance of quantum satellite communication. Therefore, in the process of quantum satellite communication, in order to ensure the reliability of quantum communication, based on the detection of ionosphere parameters, the various indexes of the satellite system should be adjusted adaptively.
Keywords: quantum satellites communication/
sporadic E/
the free electron density/
the amplitude damping channel
