UAV-aided Networks For Emergency Communications

Emergency communications play an important role in disaster management,response and recovery.High-efficiency emergency communications can reduce the loss of people's lives and wealth as much as possible when natural disasters or malicious attacks break out.The reduction of casualties and economic loss in case of disasters over time benefits from the development of communication technologies.Obviously,it is very meaningful for disaster prevention and reduc-tion,social stability to emphasise applied research of emergency communications.In recent years,unmanned aerial vehicles(UAVs)flourish in both military and civilian fields,and UAVs,depend-ing on their excellent features,such as good scalability and mobility,can provide a high-efficiency solution for emergency communications.This thesis is mainly on the communication coverage of UAV-aided networks in emergency communication scenarios.To be more specific,the main outcomes of this paper are as follows:1.We review the formation characteristics in a UAV-aided network for emergency commu-nications from the perspective of practice,then we introduce connectivity on the basis of network coverage and propose a indicator integrating coverage and connectivity to represent the performance of this emergency communication network.After modeling the scenarios of emergency communication networks composed of UAV base stations(ABSs)and users,we investigate the gains that the UAV-aided network can bring for emergency communica-tions.Through simulations,the communications in disaster-affected areas can be improved prominently by the deployment of ABSs and the performance indicator behaves well.2.In case of disasters,limited resources should be used adequately.For instance,the intact ground base stations(GBSs)should be also used to construct the emergency communica-tion system.Therefore,we study a emergency communication system composed of intact GBSs,ABSs and users.We also combine coverage and connectivity in this heterogeneous network.Through optimizing the positions of ABSs,the performance of this heterogeneous communication network can be at the best level.3.In practice,user distributions in various areas are likely to be different.According to this practical situation,we investigate the performance of the emergency communication net-work composed of ABSs and users in an disaster-affected area with two user distributions.Moreover,we also consider the case that the relative locations of these two areas are differ-ent,but results indicate that the relative positions of these two areas have almost no impact to the communication performance.