为了研究雷暴云对星地量子链路信道的影响,根据雷暴云中大气带电粒子的消光截面与数目浓度分布函数,得到了粒子浓度、电荷密度与链路衰减系数的关系。建立了粒子浓度、电荷密度与信道容量、信道平均保真度、信道生存函数和量子密钥分发系统误码率之间的关系。仿真结果表明,雷暴云对星地量子链路性能有显著的影响。所以,应根据雷暴云的预报情况,自适应调整量子卫星通信系统的各项参数,以提高星地链路的可靠性。
In order to investigate the effect of thunderstorm cloud on the performance of satellite-to-ground quantum link, according to the extinction cross section and the number concentration distribution function of the charged particle in the thunderstorm cloud, the relationships among the particle concentration, charge density and link attenuation of charged particles in atmosphere were established. The relationship between the atmospheric concentration of charged particles, the charge density on the average channel capacity, channel fidelity, channel survival fimction and bit error rate of quan- tum key distribution system were put out. The simulation results show that the thunderstorm cloud has a significant effect on the performance of the satellite-to-ground quantum link. So in order to improve the reliability of satellite-ground quantum communication, the system parameters should be adjusted according to the forecast of the thunderstorm cloud.