Research On Distributed Cooperation Strategy Considering Uavs In Heterogeneous Networks

With the development of information and communication technology,future network deployment will show a multi-standard and isomerization trend.At the same time,the number of users’ devices has exploded.In the future,tens of billions of equipment will be connected to the network,bringing tremendous pressure to the existing base stations(BSs).The demand for network communication,caching,and computing has increased dramatically.Unmanned aerial vehicle(UAV)-assisted heterogeneous networks have some advantages,such as increasing dimensions,establishing line-of-sight links,fast deployment,and low cost.These advantages can realize distributed ad-hoc networks.Meet the communication requirements of users with high speed and low delay.Relieve the service pressure of existing BSs.Therefore,UAV-assisted heterogeneous networks have attracted wide attention.In the scenario of UAVs-assisted heterogeneous network.UAVs have the advantages of flexible deployment and low cost.However,a single UAV’s capability is limited,and it is not easy to support multiple tasks.Therefore,it is necessary to consider the cooperative deployment of multiple UAVs,reasonably plan and assign multiple UAVs to complete tasks.UAV has limited energy,which affects its service life and cannot provide uninterrupted service for users.Therefore,this paper focuses on the cooperation technology of UAV-assisted heterogeneous networks.It is combining with key technologies such as UAV deployment,relay,and trajectory optimization.Aiming at the location deployment and energy consumption of UAVs,distributed cooperative deployment strategy and continuous coverage strategy are proposed.Meet the transmission rate requirements of users,reduce energy consumption and realize continuous coverage.The specific work and innovations of this paper are as follows:First,the capability of a single UAV is limited in the UAV-assisted BS scenario.In this paper,a three-dimensional deployment scheme of multi-UAVs distributed cooperation is proposed.Considering the distributed ad hoc network model of UAVs,a pre-clustering radius expansion deployment algorithm is proposed.In this algorithm,randomly distributed users are pre-clustered.Under the constraints of user transmission rate and deployment strategy,the deployment coordinates of UAVs are solved.Therefore,UAVs can greatly cover user equipment and provide services.Simulation results show that the scheme and algorithm can improve the coverage rate through UAVs’ distributed ad-hoc network.Second,aiming at the problem that UAVs have limited energy and cannot be covered continuously.In this paper,a strategy of distributed cooperation and continuous coverage of UAV is proposed.Through the cooperation between UAVs,relay,and backhaul the information to macro-BS(mBS).Inform mBS to send auxiliary UAVs to replace the UAV-BS with weak power and provide uninterrupted service.In this strategy,the energy consumption of information transmission and the flight energy consumption of auxiliary UAV are considered.Two sub-problems,relay backhaul and trajectory optimization are proposed and solved by Dijkstra and convex optimization algorithm.Simulation results show that this strategy can reduce energy consumption.