In mobile networks, unmanned aerial vehicles (UAVs) acting as flying base stations (FlyBSs) can effectively improve performance. Nevertheless, such potential improvement requires an efficient positioning of the FlyBS. In this paper, we study the problem of sum downlink capacity maximization in FlyBS-assisted networks with mobile users and with a consideration of wireless backhaul with channel reuse while a minimum required capacity to every user is guaranteed. The problem is formulated under constraints on the FlyBS's flying speed, propulsion power consumption, and transmission power for both of flying and ground base stations. None of the existing solutions maximizing the sum capacity can be applied due to the combination of these practical constraints. This paper pioneers in an inclusion of all these constraints together with backhaul to derive the optimal 3D positions of the FlyBS and to optimize the transmission power allocation for the channels at both backhaul and access links as the users move over time. The proposed solution is geometrical based, and it shows via simulations a significant increase in the sum capacity (up by 19%-47%) compared with baseline schemes where one or more of the aspects of backhaul communication, transmission power allocation, and FlyBS's positioning are not taken into account.

中文翻译：

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具有用户 QoS 保证的 UAV 移动网络回程信道复用

在移动网络中，充当飞行基站（FlyBS）的无人机（UAV）可以有效提高性能。然而，这种潜在的改进需要 FlyBS 的有效定位。在本文中，我们研究了具有移动用户的 FlyBS 辅助网络中的总下行链路容量最大化问题，并考虑了具有信道重用的无线回程，同时保证每个用户的最小所需容量。该问题是在 FlyBS 的飞行速度、推进功率消耗以及飞行和地面基站的传输功率的约束下制定的。由于这些实际限制的组合，无法应用现有的最大化总容量的解决方案。本文率先将所有这些约束与回程结合起来，以得出 FlyBS 的最佳 3D 位置，并在用户随时间移动时优化回程和接入链路上信道的传输功率分配。所提出的解决方案是基于几何的，它通过仿真表明，与回程通信、传输功率分配和 FlyBS 定位中的一个或多个方面的基线方案相比，总容量显着增加（增加 19%-47%）不被考虑在内。