The Research Of Networking And Backhaul Technologies For 5G Ultra-dense Networks

With the development of mobile communications and the growth of smart devices,the demand for the communication network is increasing,and the development of the fifth generation mobile communication(5G)has become popular in the research fields.5G has the characteristics of high speed,high frequency spectrum efficiency,large coverage and so on.As the key technology of the networking,the ultra-dense network has attracted wide attention among researchers.Intensive access points(APs)may be deployed in the ultra-dense network.The coverage rate and the speed have been improved.But it has caused a series of problem as well,such as access,backhaul,interference and so on.In such a dense-deployed environment,how to make the downlink multiple low-power APs provide efficient services for users is a great challenge.It needs consideration on the cooperation between APs,energy efficiency and interference among APs.In the backhaul,how to transmit the data back to the core network efficiently and reliable is also very important.Relative wireless backhaul technology and multi-hop routing algorithm are under developed.To solve these problems,this paper focuses on ultra-dense network downlink networking and uplink backhaul routing.In this paper,we propose a dynamic access point grouping mechanism based on energy efficiency maximization in ultra-dense networks.This system realizes the function of dynamic selection and power allocation for access point.This scheme takes terrain and network topology into consideration to divide the lots of APs into several available candidate sets(ACS).The ACS contains a variety of types of APs.The APs can be chosen from the ACS as the group member for UE's APs group.The members provide services to users in a cooperation manner.Once the service requirements change or user moves,the members of the group and resource allocation will be changed accordingly.Considering the spectrum efficiency,the mechanism is improved with dynamic allocation of bandwidth.The considered optimization problem is a discrete mixed combinational optimization problem,and a quantum-behaved particle swarm optimization(QPSO)algorithm is adopted to solve it efficiently.The mechanism solves the problem of energy loss caused by the ultra-dense deployment,and adjusts the AP selection and its power and bandwidth allocation according to the requirement of the user's service rate,and improves the flexibility of resource allocation.Through the simulation analysis,the proposed mechanism can improve the energy efficiency and the spectrum efficiency of the network.In this paper,we study the routing selection mechanism of the backhaul link in the ultra-dense network.In order to transmit the information to the core network quickly and reliably,we propose a mechanism for wireless backhaul routing selection based on the delay minimization.The mechanism takes into account the premise of existing network's load condition,and to obtain an optimal multi-hop routing path for the end-to-end delay and overhead.The mechanism adopts the method of combining ACS.Each ACS has a unique label.Local control carries on the route selection.This may reduce the signaling cost and energy consumption.In order to avoid multiple APs resource competition,a relay can only be used by one user.The mechanism solves the problems of limited wireless backhaul transmission distance and delay.The load capacity of the whole system is improved,and the time delay is reduced,with a reliable backhaul link.