Research On D2D Communication Based On Power Control

This paper focuses on the research of D2 D communication technology as one of the important technologies of mobile communication.The introduction of D2 D technology in mobile communication system can improve the spectral efficiency of communication system,reduce the delay and reduce the load of core network.with the growth of mobile devices and the limitation of battery capacity of terminal devices,how to effectively improve the energy efficiency of communication system to achieve green communication is the key to the development of mobile communication in the future and also the focus of this paper.In this paper,power control is introduced into the cellular network with D2 D communication users.In the third chapter,open loop,closed loop and joint power control are analyzed respectively,and the throughput and signal-to-noise ratio of these three power controls are simulated on the simulation platform MATLAB.Through the simulation image analysis,it can be concluded that,The performance of communication system can be improved effectively by introducing power control,and the combined power control can achieve better communication performance compared with the open loop power control and the closed loop power control.After completing this simulation,and in the open loop power control,for example,by changing the D2 D communication users maximum distance and the D2 D communication between the distribution density of these two variables to simulate again,come to the conclusion that the open loop power control the D2 D communication directly,the smaller the distance between the D2 D communication users,is the communication performance of network users is higher,However,changing the distribution density of D2 D communication users has little influence on the communication performance of D2 D communication users.Finally,on the basis of the power control introduced above,in order to better adapt to the phenomenon that the distance between D2 D communication is too far or the communication quality of D2 D communication deteriorates due to the influence of environmental factors,the k-means algorithm is introduced in chapter 4 to carry out relay selection for D2 D cooperative communication.In this paper,the communication performance of the k-means algorithm and the random relay selection algorithm mentioned in this paper are spectively simulated in AWGN channel and Rayleigh channel.By comparing the images,it can be concluded that no matter which relay selection algorithm mentioned above,The bit error rate in AWGN channel is lower than that in Rayleigh channel,and the k-means algorithm listed win this paper has a lower bit error rate than the random relay selection algorithm in either channel mentioned above.