| With the rapid development of mobile communication systems,the convenience brought by mobile communication makes it indispensable in modern life.With the official release of the world's first commercially-available 5G standard by the International Telecommunications Standards Organization on December 21,2017,the performance of future mobile network will be further enhanced.As one of the key technologies of 5G communication,D2D communication(Device-to-Device Communication)plays an important role in improving system performance,enhancing user experience,and increasing spectrum efficiency.However,D2D communication will also bring some negative effects.For example,when D2D users multiplexes the spectrum resource communication of a cellular user,there will be mutual interference between the cellular user and the D2D user,and the D2D users may also interfere with each other.As a key technology to coordinate D2D communication and cellular communication,power control mechanism plays an important role in reducing interference and improving system performance.On the other hand,the energy consumption caused by communication and computation is very large compared to the limited battery capacity of smart devices.Therefore,how to design an effective power control mechanism to reduce interference and improve energy efficiency is very important for the future 5G communications.An emerging technology named SWIPT is proposed to further improve energy efficiency.It is of great significance to study the combination of the power control mechanism and SWIPT.Specifically,this paper's contribution mainly includes the following two aspect.(1)A D2D communication model is established.With the help of game theory,a D2D utility function is defined with accordance to the established model,and the validity and convergence of such utility function is proven.The existence and uniqueness of Nash equilibrium in this game model are proved,and the corresponding centralized mechanism and distributed power control mechanism are proposed.Numerical simulations indicated that the proposed power control mechanism can effectively improve the system performance and reduce the interference between D2D communication and cellular communication.(2)A new model is established to a model SWIPT-enabled D2D communication environment.Using game theory,the utility function of such model is defined,and and the validity and convergence of such utility function is proven.The existence and uniqueness of this game Nash equilibrium are proved,and corresponding centralized mechanism and distributed power control mechanism are proposed.Numerical simulations indicates that the proposed power control mechanism can effectively improve the system performance,reduce the interference between D2D communication and cellular communication,and improve the energy efficiency.The significance of this paper lies in the following aspects.First,in D2D communication,the D2D device compensation power is defined,and game theory is also utilized to obtain power control mechanisms to improve system performance.Secondly,in D2D communication,the power control mechanism and SWIPT technology are combined with the aid of game theory,and a novel power control mechanism that can control interference and improve energy efficiency is proposed,which lays a theoretical foundation for the application of wireless energy-carrying technology to D2D communication. |
