Abstract: To support the ubiquitous connectivity requirement of sixth generation communication, unmanned aerial vehicles (UAVs) play a key role as a major part of the future communication networks. One major issue in UAV communications is the interference resulting from spectrum sharing and line-of-sight links. Recently, the application of the coordinated multipoint (CoMP) technology has been proposed to reduce the interference in the UAV-terrestrial heterogeneous network (HetNet). In this paper, we consider a three-dimensional (3D) multilayer UAV-terrestrial HetNet, where the aerial base stations (ABSs) are deployed at multiple different altitudes. Using stochastic geometry, we develop a tractable mathematical framework to characterize the aggregate interference and evaluate the coverage probability of this HetNet. Our numerical results show that the implementation of the CoMP scheme can effectively reduce the interference in the network, especially when the density of base stations is relatively large. Furthermore, the system parameters of the ABSs deployed at higher altitudes dominantly influence the coverage performance of the considered 3D HetNet.

多点协同传输机制下的多层无人机-地面异构网络覆盖性能分析

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