Research On Resource Management Of D2D Communication In Heterogeneous Cellular Networks

With the rapid development of the next generation mobile network,the number of terminal devices and applications is growing explosively.Therefore,how to obtain higher data rate,wider network coverage and higher resource utilization in the limited spectrum resources has become the common research goal of scholars.Device-to-Device(D2D)communication technology and other frontier communication technologies have emerged.Device-to-Device communication technology is the technology that devices in proximity can communicate directly in cellular networks.It has become one of the key technologies of the fifth-generation mobile communications system(5G).D2 D communication technology which is introduced into cellular networks can effectively improve spectrum utilization,enhance network coverage,reduce transmission delay and improve system throughput,but it would also bring complicated and various interferences due to reusing cellular resources at the same time.So resource management is one of the most challenging and importing issues to give full play to the advantages of D2 D communication.Based on the above background,this thesis mainly studies the related technologies and solutions of how to reasonably select the communication mode and allocate cellular resources for D2 D users in heterogeneous cellular networks.The main works and innovations of the thesis are summarized as follows:Firstly,this thesis introduces the concept of D2 D communication technology and main gain characteristics.And the thesis compares it with other short-range wireless communication technologies in many aspects.Then the thesis introduces the process of D2 D device discovery and conversation establishment,four kinds of interference scenarios of D2 D users reusing cellular resources and four kinds of communication modes.The thesis discusses the reasons of D2 D users reusing the upstream link resources.Besides,the thesis summarizes the power control algorithm used to control interference and the application scenarios of D2 D communication technology.Secondly,aiming to solve the problem which is D2 D users get poor service quality in traditional communication mode but D2 D users will bring interferences if they reuse Macro user's resources,a mode selection algorithm based on position limitation and Vickrey-ClarkeGroves(VCG)auction was proposed in order to select the optimal communication mode for D2 D users.Macro users were divided into two groups according to their location and the signal to interference plus noise ratio(SINR)of MUE and D2 D receivers.Then,the process of selecting communication mode for D2 D users and selecting the best resources for D2 D users in reusing mode were designed as a forward auction process of single item on the basis of VCG auction model.The simulation results show that the algorithm can select the optimal communication mode for D2 D users and improve the system throughput and the spectral efficiency.Finally,for the situation that the number of D2 D users is far more than the number of uplink resources,a resource allocation algorithm based on position limitation was proposed for D2 D users.According to the signal to interference plus noise ratio of D2 D receiver and the positions of D2 D users,the interference chart is constructed.Then,use the graph-coloring theory to cluster the D2 D users.The reconstruction of clusters produced is made to provide the QoS for all users.The allocation of the reconstructed clusters is the last step.The simulation results show that the algorithm can increase the ratio of D2 D users access network and improve the system throughput and the spectral efficiency.