Coverage performance of the multilayer UAV-terrestrial HetNet with CoMP transmission scheme

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.

Satellite Constellation Design with Multi-Objective Genetic Algorithm for Regional Terrestrial Satellite Network

Constellations design for regional terrestrial-satellite network can strengthen the coverage for incomplete terrestrial cellular network. In this paper, a regional satellite constellation design scheme with multiple feature points and multiple optimization indicators is proposed by comprehensively considering multi-objective optimization and genetic algorithm, and "the Belt and Road" model is presented in the way of dividing over 70 nations into three regular target areas. Following this, we formulate the optimization model and devise a multi-objective genetic algorithm suited for the regional area with the coverage rate under simulating, computing and determining. Meanwhile, the total number of satellites in the constellation is reduced by calculating the ratio of actual coverage of a single-orbit constellation and the area of targets. Moreover, the constellations' performances of the proposed scheme are investigated with the connection of C++ and Satellite Tool Kit(STK). Simulation results show that the designed satellite constellations can achieve a good coverage of the target areas.

Satellite Constellation Design with Adaptively Continuous Ant System Algorithm

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.