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 communicat...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.展开更多
The ant system algorithm (ASA) has proved to be a novel meta-heuristic algorithm to solve many multivariable problems. In this paper, the earth coverage of satellite constellation is analyzed and a n + 1^ -fold cov...The ant system algorithm (ASA) has proved to be a novel meta-heuristic algorithm to solve many multivariable problems. In this paper, the earth coverage of satellite constellation is analyzed and a n + 1^ -fold coverage rate is put forward to evaluate the coverage performance of a satellite constellation. An optimization model of constellation parameters is established on the basis of the coverage performance. As a newly developed method, ASA can be applied to optimize the constellation parameters. In order to improve the ASA, a rule for adaptive number of ants is proposed, by which the search range is obviously enlarged and the convergence speed increased. Simulation results have shown that the ASA is more quick and efficient than other methodV211.71s.展开更多
基金Project supported by the Beijing Natural Science Foundation,China(No.L202015)the National Natural Science Foundation of China(No.62001029)the Young Talents Supporting Project of China Association for Science and Technology。
文摘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.
文摘The ant system algorithm (ASA) has proved to be a novel meta-heuristic algorithm to solve many multivariable problems. In this paper, the earth coverage of satellite constellation is analyzed and a n + 1^ -fold coverage rate is put forward to evaluate the coverage performance of a satellite constellation. An optimization model of constellation parameters is established on the basis of the coverage performance. As a newly developed method, ASA can be applied to optimize the constellation parameters. In order to improve the ASA, a rule for adaptive number of ants is proposed, by which the search range is obviously enlarged and the convergence speed increased. Simulation results have shown that the ASA is more quick and efficient than other methodV211.71s.