低仰角动态环境下高空平台站通信信道的衰落特性研究

在分析了高空平台站通信系统的覆盖特性、链路损耗特性与降雨衰减特性的基础上，针对低仰角动态环境下的信道特性，根据传播散射理论，通过引入阴影系数A，建立了一个包含“好状态”和“坏状态”的混合状态衰落统计模型，而且在“坏状态”下根据阴影遮蔽的程度又分为两种情形。针对不同状态得到了模型的一阶和高阶统计特性，并通过实测数据进行验证，发现两者吻合良好。证明该模型可用于高空平台站通信电波传播特性的分析、调制及编码方案的优化和通信系统性能仿真等方面的研究。

Research on Fading Characteristics of the HAPS Communication Channel under Low Elevation Angle Dynamic Environments

Analyzed the coverage characteristics, link loss characteristics and also rain attenuation characteristics of the HAPS communications system. Against the channel characteristics of low elevation dynamic environments, a mixed state fading statistical model was proposed according to propagation scattering theory, through the introduction of the shadow coefficient A. The channel model includes a “good state” and a “bad state”, and the “bad state” is divided into two situations according to the shadow obscured extent. Derived the first order and higher order statistical characteristics of the model, against different states. Furthermore, compared the first order and higher order statistical characteristics of the model through the measured data, and found the two have good agreement. It proved that the model can be used to analyze the propagation characteristics, optimize the modulation and coding schemes and performance simulation of the HAPS communication systems.