Research On Resource Allocation Algorithms For D2D Communication In Mobile Communication Network

In the dual context of rapid development of the Internet of Things technology and the upcoming of 5G commercialization,explosive growth of large-scale terminal equipments and continuous emergence of new services have brought huge challenges to the existing communication network architecture.In order to solve the problems of spectrum resource scarcity,low transmission rate and high communication delay,device to device(D2D)technology came into being.D2 D communication technology is listed as one of the key technologies of the fifth generation mobile communication.It can carry out direct communication between devices without base station forwarding,which can effectively alleviate the lack of spectrum resources,improve spectrum utilization,increase system throughput,and improve user satisfaction.However,the introduction of D2 D communication technology inevitably brings interference to the original cellular users in the network.In order to control the interference reasonably and improve the system performance,the technical advantages of D2 D communication can be brought into play by making reasonable resource allocation to D2 D users.Based on the above research background,this paper focuses on the application scenarios where D2 D users multiplexing uplink channels of cellular users in a single cell,focusing on the two resource allocation methods of a pair of D2 D users to a cellular user and multiple pairs of D2 D users to a cellular user.And proposed two D2 D resource allocation algorithms The specific content is as follows:1.In view of the case that the number of D2 D users in cellular network does not exceed the number of cellular users,a one-to-one resource allocation method is adopted,and a D2 D resource allocation algorithm based on social centrality is proposed.In order to allow important D2 D nodes in the network to reuse channel resources preferentially,the concept of closeness centrality in social networks is introduced as an index to measure the importance of D2 D users in the network,andresources of higher importance D2 D users are preferentially allocated.Considering that some D2 D users wait a long time for resource allocation,an interference limiting area is set,and D2 D users with a low degree of closeness are allocated channels using the KM algorithm in graph theory.The algorithm presented in this paper effectively increases system throughput and improves user satisfaction.2.In view of the case that the number of cellular users in a cellular network is less than the number of D2 D users,a many-to-one resource allocation method is adopted,and a D2 D interference control and resource allocation algorithm is proposed.According to the actual needs of users in the network,based on the clustering of D2 D users with fuzzy c-means algorithm,a new clustering algorithm of D2 D users based on improved graph coloring is proposed to reduce the mutual interference of users in the cluster.This algorithm determines the coloring order according to the importance of users in the network.Subsequently,the D2 D channel allocation problem is transformed into the RGCP problem,and the channel allocation with the minimum system interference value is realized on the basis of fully considering the tolerable and intolerable interference of all users in the cellular network,so as to achieve the goal of suppressing interference and improving system throughput.