Abstract: The ionosphere E layer is an important part of the atmosphere, which contains a large number of charged ions that will have an impact on the quantum signals passing through the ionosphere E layer. Therefore, this paper studies the influence of the ionospheric E layer on the characteristics of the satellite-to-earth quantum key distribution system using three different wavelengths. A transmission model of the ionospheric E layer is established first and then it is used to analyze the influence of the solar zenith angle and transmission distance on the link attenuation of the signal with three different wavelengths. In addition, simulations of the channel capacity, entanglement fidelity, quantum bit error rate, and secret-key rate as a function of solar zenith angle and transmission distance are performed. The results show that, in order to obtain better quantum communication characteristics, it is recommended using short-wavelength signals in practice, and to run communication at the time that avoid noon.

Key words: quantum key distribution, the ionospheric E layer, channel capacity, entanglement fidelity, quantum bit error rate, secret-key rate