Beam Management And Performance Analysis For User-centric UAV Station Networks

With the commercial application of 5G and the proposed concept of B5G,UAV communication has become the research direction of academia and industry.On the one hand,the UAV base station can assist the traditional communication network as an auxiliary device to improve the network performance;on the other hand,because the UAV has the advantages of convenient deployment,flexible configuration and relatively low cost,it can meet the needs of high coverage and large capacity dynamic business.In order to further improve the UAV communication data capacity,beam communication is applied to UAV base stations,including millimeter wave narrow beam communication and wide beam communication.Therefore,this paper mainly studies the beam management process and algorithm of the user-centric UAV base station networks,and analyzes the beam coverage of the UAV base station networks in special scenarios using the stochastic geometry tools,which would be used to guide the deployment of UAVs.The main work of this paper is divided into the following two parts:Firstly,the initial beam access process of the user-centric UAV base station networks is analyzed.Based on the uplink reference signals sent by users,the user-centric UAV base station networks is established.According to the characteristics of inactive users,the uplink measurement based beam management process is proposed,which enables users to complete the initial beam access in the inactive state.Through numerical analysis and Monte Carlo simulation,it can be proved that there are gains in initial access delay,link performance and capacity domain performance.Secondly,the beam coverage performance of user-centric UAV base station networks in urban environment is analyzed.Based on the actual wide beam model,the deployment height and the beam pitch angle of the UAV base stations limit the coverage range of a single UAV.When analyzing the beam channel model in the urban environment,the occlusion effect of build ings needs to be considered.Therefore,a three-dimensional building block model is established and then beam coverage of UAV base station networks in this scene is obtained by using the stochastic geometry tool.Through simulation,the influence of UAV characteristics and building characteristics on the beam coverage of UAV base station networks is verified,which provides guidance for the deployment of UAVs in this scenario.