临近空间UAV路径衰落的自适应Markov模型*

在分析临近空间UAV（无人机）飞行特征的基础上，根据临近空间UAV的飞行状态——发射和降落状态、航空飞行状态、飞行盘旋状态，结合临近空间的物理环境，建立了临近空间长航时UAV路径衰落的自适应Markov模型，提出了具体的理论分析过程和实现方法；给出了各个状态下动态信道的路径衰落理论计算式，最后实现了临近空间UAV自适应Markov路径衰落模型的自由空间衰落、双径衰落和多径衰落仿真，从而保证了模型的可靠性。仿真得出：在临近空间UAV的通信中，其路径衰落主要考虑自由空间衰落量和反射分量，但多径分量不容忽视。

Adaptive Markov model for channel path fading of near space UAV

Based on the analysis of the special characteristics of the flight about the near space unmanned aircraft vehicle(UAV), this paper built an adaptive Markov model for the channel path fading of the near space UAV according to the three major flights scenarios: circled, en-route, taking off and landing, and the physical environment of the near space. Then analyzed and gave the calculation about the channel path fading of the flight scenarios. At last, carried out the simulation of the free spatial fading, two-path fading and multipath fading about the adaptive Markov model for the channel path fading of the near space UAV. The result verifies the reliability of the modal and the effect of the multipath fading is less than others.