基于无人机辅助的V2I无线传输系统性能优化

Performance optimization for UAV-enabled V2I communications system

在应急通信中,无人机的应用越来越广泛,提出了一种无人机辅助的V2I(vehicle to infrastructure)车载通信技术。由于通信距离、地形遮挡等原因,地面的车辆与基站可能无法实现直接通信,此时无人机可被用作通信中继。在通信过程中,为了满足地面车辆通信的公平性需求,基于地面移动车辆的位置坐标,选定一个小于相干时间的时间间隔,计算车辆在每个时间间隔的传输速率,并将最大化最小传输速率作为优化目标。为解决此问题,提出将整个通信过程离散化,先计算在每个时间间隔范围内使最小传输速率最大化的无人机飞行轨迹,从而得到整个通信过程的无人机飞行路径。仿真表明,通过对无人机进行路径规划,车辆的信息传输速率明显优于无人机位置固定情况下的传输速率。

In the emergency communication, UAVs(unmanned aerial vehicle) are used more and more widely, and a V2I(vehicle to infrastructure) vehicle communication technology based on UAV was proposed. Because of the communication distance and the shelter of the terrain, the ground vehicle and the base station may not connect directly. At this time, the UAV can be used as communication relay. In the process of communication, in order to meet the fairness of ground vehicle communication, a time interval less than the coherence time was selected based on the coordinates of moving ground vehicles, the transmission rate between vehicles in each time interval are calculated to maximize the minimum transmission rate as the optimization goal. In order to solve this problem, the entire communication process was dispersed. First, UAV flight trajectory to maximize the minimum transmission rate at each time interval within the range of the UAV flight path was calculated to get the whole communication process trajectory. Simulation results show that through the path planning of UAV, the information transmission rate of the vehicle is obviously better than the transmission rate under the fixed position of UAV.