Research On Resource Allocation And Interference Control Algorithms Based On Game Theory In D2D Networks

With the development of mobile communication technologies,the demand for wireless multimedia services has grown rapidly in modern life.At the same time,the shortage of spectrum resources has become increasingly serious.How to make full use of the limited spectrum resources has become a hot topic of research.Device-to-Device(D2D)technology can improve the spectrum utilization by multiplexing the spectrum resources of the cell,effectively reduce the load on the base station,and can communicate without a network infrastructure,ensuring the QoS(Quality of Service)of the network and Robustness.According to the D2 D user multiplexing spectrum resources,it can be divided into orthogonal mode(also called overlay mode)and multiplexing mode(also called underlay mode).When D2 D communication is introduced in a mobile cellular network,new spectrum resource competition and mutual interference problems will arise.For this reason,this paper uses game theory as a tool to study the problem of resource allocation and interference control in D2 D communication.The main research work is as follows:For D2 D users working in overlay mode,considering multiple base stations and cognitive D2 D user pairs,Bertrand game model is used to solve the problem of dynamic spectrum allocation.Firstly,the game between cellular users and D2 D vs.user groups in D2 D communication is analyzed.The utility function of D2 D to user groups and base stations is improved respectively,and a new dynamic spectrum allocation algorithm based on non-cooperative game is proposed.Further,the base station's optimal pricing and D2 D dynamic pricing adjustment strategy for the user group are given.The revenue function of the cellular user and D2 D pair user group is improved,and the existence of the Nash equilibrium solution and the convergence of the algorithm are proved.The convergence speed of dynamic game algorithm under the influence of different learning factors is discussed.Finally,through simulation experiments,it is verified that the proposed algorithm improves the spectrum efficiency and fairness of the system.For multiple D2 D pairs when multiplexing cellular user channel resources in underlay mode,there are interference problems between D2 D users and between D2 D users and cellular users.Considering that the base station and the D2 D transmit end have multiple antennas,this document satisfies the rated emission.Under the conditions of power and user quality of service,with the goal of maximizing system weights sum rate and taking into account user fairness,a distributed beamforming algorithm for non-cooperative games based on price strategy is proposed.Since the objective function is non-convex,first,we use the dual decomposition method to find the solution to the KKT condition of the downlink beamforming problem for each sender.Second,we propose a distributed beamforming algorithm based on non-cooperative games which can quickly converge to Nash equilibrium point with a lower information exchange overhead.Finally,simulation comparison experiments show that compared with the existing typical algorithms,the proposed algorithm has a great improvement in the system's sum rate and fairness.