Research On User Association And Base Station Slpeep Strategy In Heterogeneous Cellular Networks

With the advent of 5G,the research of heterogeneous network has attracted the attention of a large number of scholars.With the intensification of base stations in heterogeneous networks,it is an inevitable trend to develop green communications by protecting the environment and reducing the energy consumption of the communication industry.The user association and the base station sleep strategy is one of the important researches.Based on the above two questions,this paper focuses on the problem of user association and base station sleep strategy in heterogeneous cellular networks.Firstly,the knowledge of heterogeneous cellular network is briefly introduced,consist of user association,energy efficiency and knowledge of quasi convex functions and greedy algorithm involved in this paper.Secondly,we investigate the base station sleep problem of small cell networks.A constrained optimization problem for minimizing the number of activated base stations is constructed.Based on the idea of greedy algorithm,the base station and the user are associated once.In order to further reduce the number of activated base stations,a sleep algorithm is proposed for base station sleep and secondary user association.And the effectiveness and superiority of the algorithm are verified through simulation.Finally,we investigate the base station sleep problem of heterogeneous cellular networks,and a constrained optimization problem of maximizing user energy efficiency is constructed.This problem is transformed into two sub-problems,namely user association problem and power control problem.For the problem of user association,the iterative algorithm is used for user association and base station sleep,and the distributed algorithm is used to solve the power control problem.The effectiveness of the proposed algorithm is verified by simulation.