This paper investigates the rotary-wing unmanned aerial vehicle (UAV)-enabled full-duplex wireless-powered Internet-of-Things (IoT) networks, in which a rotary-wing UAV equipped with a full-duplex hybrid access point (HAP) serves multiple sparsely-distributed energy-constrained IoT sensors. The UAV broadcasts energy when flying and hovering, and collects information only when hovering. It is assumed that the transmission range of the UAV is limited and the sensors are sparsely distributed in the IoT network. Under these practical assumptions, we formulate three optimization problems: a sum-throughput maximization (STM) problem, a total-time minimization (TTM) problem, and a total-energy minimization (TEM) problem. For the TEM problem, we further take into consideration that the power needed for hovering, flying, and transmitting are different. For the STM, TTM and TEM problems, optimal solutions are obtained. Finally, numerical results show that the performance achieved by the proposed optimal time allocation schemes outperform existing time allocation schemes. It is also observed that i) the time allocation between hovering and flying time has different trends for different goals; ii) there is an optimal UAV transmit power range that minimizes the energy consumed by the UAV during the entire cycle.

中文翻译：

---

全双工旋翼无人机无线供电物联网网络的优化

本文研究了支持旋翼无人机 (UAV) 的全双工无线供电物联网 (IoT) 网络，其中旋翼无人机配备了全双工混合接入点 (HAP)为多个稀疏分布的能源受限物联网传感器提供服务。无人机在飞行和悬停时广播能量，仅在悬停时收集信息。假设无人机的传输范围有限且传感器在物联网网络中分布稀疏。在这些实际假设下，我们制定了三个优化问题：总和吞吐量最大化 (STM) 问题、总时间最小化 (TTM) 问题和总能量最小化 (TEM) 问题。对于TEM问题，我们进一步考虑了悬停、飞行和发射所需的功率不同。对于 STM、TTM 和 TEM 问题，获得了最优解。最后，数值结果表明，所提出的最佳时间分配方案实现的性能优于现有的时间分配方案。还观察到 i) 悬停和飞行时间之间的时间分配对于不同的目标有不同的趋势；ii) 存在一个最优的无人机发射功率范围，使无人机在整个周期内消耗的能量最小。