Unmanned Aerial Vehicles (UAVs) offer promising potential as communications node carriers, providing on-demand wireless connectivity to users. While existing literature presents various wireless channel models, it often overlooks the impact of UAV heading. This paper provides an experimental characterization of the Air-to-Ground (A2G) and Ground-to-Air (G2A) wireless channels in an open environment with no obstacles nor interference, considering the distance and the UAV heading. We analyze the received signal strength indicator and the TCP throughput between a ground user and a UAV, covering distances between 50~m and 500~m, and considering different UAV headings. Additionally, we characterize the antenna's radiation pattern based on UAV headings. The paper provides valuable perspectives on the capabilities of UAVs in offering on-demand and dynamic wireless connectivity, as well as highlights the significance of considering UAV heading and antenna configurations in real-world scenarios.

翻译：无人驾驶飞行器（UAV）作为通信节点载体具有广阔前景，可为用户提供按需无线连接。现有文献提出了多种无线信道模型，但常忽略无人机航向的影响。本文在无障碍物与干扰的开阔环境中，针对空对地（A2G）与地对空（G2A）无线信道开展实验表征，考虑了距离与无人机航向因素。我们分析地面用户与无人机之间的接收信号强度指示和TCP吞吐量，覆盖50米至500米的距离范围，并考虑不同无人机航向。此外，我们还基于无人机航向对天线辐射方向图进行了表征。本文为无人机提供按需动态无线连接的能力提供了有价值的见解，同时突显了在实际场景中考虑无人机航向与天线配置的重要性。