With the development of smart cities, the use of unmanned aerial vehicles (UAVs) for interactive information exchange between air and ground can provide effective support for the deployment of emergency work. However, the existing UAV air-to-ground channels often use a single channel model. Considering that the density and distribution of obstructions on information transmission paths at different heights are different, only using a single channel model greatly affects the reliability of communications. Aiming at addressing the different channel characteristics of air-to-ground channels at different heights, a height-based adaptive SUUL-SULA channel model is proposed in this paper. Firstly, in the ultra-low altitude environment, the influence of large-scale fading and small-scale fading on the envelope of the received signal is discussed based on the classic LOO model, and the probability density function and bit error rate model of the received signal are derived. Secondly, a SULA channel model based on Jakes’ model is proposed in the low-altitude environment. The uniform circular array beamforming technology is adopted to realize the design of the Doppler frequency shift compensation algorithm. Finally, the simulation results show that the SUUL-SULA model effectively reduces the bit error rate of the system and improves the reliability of communication. Therefore, this model can provide effective physical support for the application of UAV in smart city emergency management.

中文翻译：

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城市应急管理中无人机通道建模与性能优化

随着智慧城市的发展，利用无人机进行空地交互信息交互，可以为应急工作部署提供有效支撑。但是，现有的无人机空地通道往往采用单通道模式。考虑到不同高度的信息传输路径上障碍物的密度和分布是不同的，仅使用单一信道模型就极大地影响了通信的可靠性。针对不同高度空地通道的不同通道特性，本文提出了一种基于高度的自适应SUUL-SULA通道模型。首先，在超低空环境下，基于经典的LOO模型，讨论了大尺度衰落和小尺度衰落对接收信号包络的影响，推导出了接收信号的概率密度函数和误码率模型。其次，提出了一种基于Jakes模型的低空环境下的SULA信道模型。采用均匀圆形阵列波束赋形技术实现多普勒频移补偿算法的设计。最后，仿真结果表明，SUUL-SULA模型有效地降低了系统的误码率，提高了通信的可靠性。因此，该模型可为无人机在智慧城市应急管理中的应用提供有效的物理支撑。推导出接收信号的概率密度函数和误码率模型。其次，提出了一种基于Jakes模型的低空环境下的SULA信道模型。采用均匀圆形阵列波束赋形技术实现多普勒频移补偿算法的设计。最后，仿真结果表明，SUUL-SULA模型有效地降低了系统的误码率，提高了通信的可靠性。因此，该模型可为无人机在智慧城市应急管理中的应用提供有效的物理支撑。推导出接收信号的概率密度函数和误码率模型。其次，提出了一种基于Jakes模型的低空环境下的SULA信道模型。采用均匀圆形阵列波束赋形技术实现多普勒频移补偿算法的设计。最后，仿真结果表明，SUUL-SULA模型有效地降低了系统的误码率，提高了通信的可靠性。因此，该模型可为无人机在智慧城市应急管理中的应用提供有效的物理支撑。采用均匀圆形阵列波束赋形技术实现多普勒频移补偿算法的设计。最后，仿真结果表明，SUUL-SULA模型有效地降低了系统的误码率，提高了通信的可靠性。因此，该模型可为无人机在智慧城市应急管理中的应用提供有效的物理支撑。采用均匀圆形阵列波束赋形技术实现多普勒频移补偿算法的设计。最后，仿真结果表明，SUUL-SULA模型有效地降低了系统的误码率，提高了通信的可靠性。因此，该模型可为无人机在智慧城市应急管理中的应用提供有效的物理支撑。