The Research Of Secrecy-oriented Adaptive Clustering Scheme And Transmitting Mechanism

With the advent of the "Internet +",the requirements of bandwidth and quality of service in wireless access network are becoming higher and higher,some problems such as scarcity of spectrum or high energy consumption of terminals are exposing sharp in the existing network.As a new technology which has been suggested in next-generation 3GPP protocols,D2D communication enables direct communication between terminals under the control of the eNodeB.Taking advantages of D2D communication,both the load of the eNodeB and the energy consumption of the terminal significantly turn lower,improving the spectral efficiency to several times.The topics of this paper are precisely under the background of the D2D communication in wireless access network.In this paper,it firstly describes the background of the research,analyzes the significance of the research,Meanwhile,the content and the corresponding structural arrangements have been specified.Based on researching the status of D2D communication in next generation of 3 GPP protocols,it mainly focuses on the analysis of existing clustering strategies and secure transport mechanism in wireless access network,finding insufficiency,suggesting improvements and innovation,then giving out a D2D adaptive secrecy clustering scheme and a hierarchical intracluster transmitting mechanism considering secrecy of D2D users.Considering the multiple domains information such as physical domain and social domain which can effect the terminal users on behaviors of communicating,the paper proposed a D2D secrecy clustering scheme based on Kmeans algorithm.It mainly takes the physical location of terminal users and their characteristics of social trust into consideration,modifying the traditional Kmeans algorithm to realize the rapid formation of clusters,and then in order to improve the transmitting secrecy between D2D users in cluster,the scheme reassign the users in the margin of cluster into the adjacent clusters.The final simulation results show that the D2D secrecy clustering scheme allows a certain number of D2D users adaptively forming into several clusters.Compared with the existing cluster strategies,it can achieve two aims,enhancing the secrecy and reducing energy consumption of the whole cluster.Finally,the secrecy clustering scheme we proposed above may also follow with some performance variation of secrecy while communicating,so there proposes a hierarchical and secrecy transmission mechanism based on clustering results.In view of that there exists low-privileged users in the cluster and eavesdroppers out of the cluster,we decide to use a hybrid transmitting mechanism combining broadcasting with end-to-end signal sending.Specifically,when all high-privileged users in the cluster need to know some sensitive information,the cluster head will firstly broadcast this information to those high-privileged users nearby,and it will also select a cooperative jammer to send an interference signal using beamforming simultaneously,leading to low-privileged user "blind" when receiving.Secondly,cluster head will send sensitive information to the marginal high-privileged users by using time reversal processing,then the channel between source and destination will get better,the channel between source and eavesdroppers will even get worse,so that the destination nodes can receiver clearly,and eavesdroppers can hardly receive useful information.The simulation results show that,compared with traditional mechanism,the hybrid and hierarchical transmitting mechanism has a significant improvement on performance of secrecy,reducing energy consumption,and saving time.