Research On Resource Allocation Of D2D Communication Based On Cellular Network And NOMA Technology

The demand for wireless mobile data traffic has increased exponentially.However,due to the limitations of infrastructure deployment and the shortage of spectrum resources,mobile communication networks are facing serious challenges,and the most important of which is the demand of greater capacity and more connected users.In order to adapt the requirements and application scenarios of 5G,the resource allocation scheme of D2 D communication based on cellular network and NOMA are studied with considering the number of connection users,system throughput and other requirements.The main work of this thesis is as follows:Firstly,the research background and significance of NOMA technology and D2 D communication are expounded,and the current research status of NOMA technology and D2 D technology are analyzed.The system model of NOMA,the basic principles,the key technologies used,the advantages of the technology and the application scenarios are briefly introduced.And the basic concepts of D2 D technology,the mechanism of device discovery,the strategy of resource allocation and the type of mode selection are introduced.Then,D2 D technology is used in cellular networks to improve spectrum utilization and overall communication capacity of the system,considering the interference problem caused by multiplexing the spectrum resources of cellular networks,a linear programming problem is studied and a resource allocation algorithm is proposed based on the established communication system model.By traversing the interference matrix between all the D2 D users and the cellular users to get the minimum interference value,assigns the Non-Orthogonal Sharing resource to the corresponding D2 D users.Allocates dedicated communication resources to the remaining D2 D users after the multiplexed communication resources are allocated.The simulation results show that the proposed algorithm can reduce the interference of D2 D users to the cellular users significantly and increase the number of D2 D users greatly.Finally,considering the spectrum utilization of cellular system and the overall communication capacity of the system,a D2 D group communication system model is established by combining NOMA technology with D2 D technology.Based on the considered framework and the optimization target of maximum total rate of the cellular network system,an effective resource allocation scheme based on weighted bipartite graph algorithm is proposed and then obtains the power allocation scheme of each D2 D group by converting the power allocation factor into an unknown quantity.The simulation results show that the proposed algorithm can greatly increase the number of D2 D user groups and the total rate of cellular system.