Rapid Deployment of UAVs Based on Bandwidth Resources in Emergency Scenarios

In an air-space-ground integrated network for emergency scenario, assisted by the satellites, the UAVs (Unmanned Aerial Vehicle) are used as base stations that serve the ground users to recover the communications of the disaster area. The deployment delay of the UAVs greatly affects the rescue efficiency. Meanwhile, due to limited number of the UAVs, each UAV should spare it effort to serve the ground users. In the aim of solving above problems, we have designed a method for deploying UAVs. In this paper, we study how to minimize the number and deployment delay of UAVs, which is divided into three steps to solve the problem of UAVs' deployment. First, a K-Means algorithm (UB-K-Means) based on users' bandwidth requirements is proposed to cluster the ground users and determine the two-dimensional coordinates of UAVs. With such cluster algorithm, the UAVs' number can be decreased. In addition, we considered the bandwidth carried by the UAV. Then, the UAV's transmit power, the channel gain of per unit distance, the threshold of SNR, the ground user's noise power, and the UAV's coverage radius is used to determine the UAV's altitude. Finally, the UAVs are deployed to the specified location with the goal of minimizing deployment delays. The simulation results show that the proposed algorithm can achieve a small number of UAVs and a low deployment delay.