Drones are being increasingly used to create new services and support the expansion of existing applications based on communication networks due to their flexibility and potential coverage. However, drone control and safety guarantees are difficult to attain, especially when drones fly beyond visual line of sight. To address this problem, we consider the real-time location awareness of drones flying beyond visual line of sight. In this article, we first introduce trends concerning location awareness of drones and our developed system exploiting the 400 MHz frequency band. Then, experimental results validate the performance of the developed system in terms of radio propagation and delay performance, and we further confirm the effectiveness of the system in practical settings.

中文翻译：

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无人机视线飞行利用400 MHz频段的位置感知系统

由于无人机的灵活性和潜在覆盖范围，它们越来越多地用于创建新服务和支持基于通信网络的现有应用程序的扩展。但是，无人机控制和安全保证很难实现，尤其是当无人机飞出视线之外时。为了解决这个问题，我们考虑了无人机飞越视觉范围之外的实时位置感知。在本文中，我们首先介绍有关无人机位置感知的趋势以及我们利用400 MHz频段开发的系统。然后，实验结果在无线电传播和延迟性能方面验证了所开发系统的性能，并且我们进一步确认了该系统在实际环境中的有效性。