Research On Mode Selection And Resource Allocation Of Device-to-Device Communication

With the development of wireless communication,the number of global mobile users will explosively increase in the future,and the demand of mobile broadband will also experience the unprecedented rise.Limited wireless spectrum resources become the key problem that limits the development of modern mobile communication technology.To solve the bottleneck problem of spectrum scarcity in wireless communication,Most prior related work focuses on these current key technologies mainly including cognitive radio technology,intensive network,and Device-to-Device communication(D2D).D2 D communication technology is a key technology of 5G,which improves the spectrum resource utilization by allowing the adjacent users directly reuse cellular resources.The introduction of D2 D communications in cellular networks can significantly improve the network performance,but it will induce the co-channel interference between D2 D users and cellular users,which will,more or less,affect the spectrum utilization efficiency.The current domestic and foreign research mainly solve the co-channel interference among users through the D2 D communication session establishment,mode selection,resource allocation and power control.Especially,both mode selection and resource allocation are the most effective way to eliminate the interference and improve the spectrum utilization.To reduce the mutual co-channel interference among the users and take full advantage of the D2 D communication,this paper mainly studies mode selection and resource allocation.The main work of this paper is as follows:1.Considering the co-channel interference among the D2 D users in the dedicated mode,this paper proposes a dedicated sub-channels sharing agreement.And then we propose a D2 D communication resource allocation scheme that includes jointly sub-channel allocation and power allocation.Based on the proposed scheme,this paper settles the mixed integer programming problem of channel allocation factor,D2 D transmitter power,and the cellular user transmission power parameters,and maximize sum rate of all D2 D users.In the programming problem,we achieve the optimal sub-channel allocation through greedy algorithm and optimize powerallocation by genetic algorithm.The simulation results show that the proposed the D2 D communication resource allocation scheme in this paper can significantly improve the D2 D user's transmission rate and spectrum efficiency.2.When cellular users and D2 D users coexist in the same network,the channel quality of D2 D user will have different effects on mode selection.In this paper,we propose a joint mode selection and resource allocation scheme of D2 D communication,which is based on the channel power gain ratio of D2 D users.According to the channel power gain ratio,we choose D2 D communication mode for the D2 D users,Then we take D2 D users' sum rate as the optimization goal,we assign channel for different D2 D users by employing the sub-channel allocation scheme based on greedy algorithm,and we allocate power respectively for D2 D users on cellular channel,reuse channel or dedicated channels using the method of Lagrangian multiplier,method of bisection and genetic algorithm(GA).Simulation results show that the proposed adaptive D2 D communication mode selection and resource allocation scheme can fully utilize spectrum and power resources,and further improve spectrum efficiency and energy efficiency.