标题： 空天地一体化网络中用于数据卸载的无人机轨迹规划与低轨卫星选择联合方法 显示英文标题

标题： Joint UAV Trajectory Planning and LEO Satellite Selection for Data Offloading in Space-Air-Ground Integrated Networks

摘要： 随着低地球轨道（LEO）卫星和无人机（UAV）的发展，空天地一体化网络（SAGIN）成为下一代网络的主要趋势。然而，由于异构通信的不稳定性和SAGIN的时间变化特性，满足远程物联网（IoT）的数据采集和卸载需求具有挑战性。本文研究了SAGIN中的两阶段分层数据上行模型。具体而言，无人机优化轨迹以实现从物联网设备高效采集数据，然后将其传输到具有计算能力的LEO卫星进行进一步处理。该问题被建模为最小化物联网设备、无人机和LEO卫星的总能耗。由于该问题是混合整数非线性规划问题且难以直接求解，我们将其分解为两个阶段。在物联网-无人机阶段，设计了联合优化物联网配对、功率分配和无人机轨迹的算法。考虑到LEO卫星的高动态特性，在无人机-LEO阶段提出了与卫星工具包结合的实时LEO卫星选择机制。最后，仿真结果表明所提出算法的有效性，与基准算法相比，能耗减少了约10%。 显示英文摘要

摘要： With the development of low earth orbit (LEO) satellites and unmanned aerial vehicles (UAVs), the space-air-ground integrated network (SAGIN) becomes a major trend in the next-generation networks. However, due to the instability of heterogeneous communication and time-varying characteristics of SAGIN, it is challenging to meet the remote Internet of Things (IoT) demands for data collection and offloading. In this paper, we investigate a two-phase hierarchical data uplink model in SAGIN. Specifically, UAVs optimize trajectories to enable efficient data collection from IoT devices, and then they transmit the data to LEO satellites with computing capabilities for further processing. The problem is formulated to minimize the total energy consumption for IoT devices, UAVs, and LEO satellites. Since the problem is in the form of mixed-integer nonlinear programming and intractable to solve directly, we decompose it into two phases. In the IoT-UAV phase, we design the algorithm to jointly optimize the IoT pairing, power allocation, and UAVs trajectories. Considering the high dynamic characteristics of LEO satellites, a real-time LEO satellite selection mechanism joint with the Satellite Tool Kit is proposed in the UAV-LEO phase. Finally, simulation results show the effectiveness of the proposed algorithms, with about 10% less energy consumption compared with the benchmark algorithm.