Research On Resource Allocation Scheme In 5G Networks Based On User Mobility

With the rapid development of smart mobile applications,the better transmission quality is required from mobile users,driving the progress and the innovation of mobile communication technologies.In order to support low latency,low power consumption and ultra high rate transmission requirements in 5G networks,the small cell network(SCN)is widely deployed and a new user state at the radio resource control layer is proposed.The new user state result in significant challenges of the network architecture.On the one hand,due to the limited coverage of small cells,there could be frequent handover between cells according to users mobility.On the other hand,the coverage of small cells is overlapped,and the edge users will suffer severe inter-cell interference.Inactive state,with the low energy consumption characteristics,becomes the main state of users in 5G networks.In order to effectively manage the mobility of inactive users,this thesis studies the mobility management problem of inactive users in SCNs and proposes a user-assisted dynamic radio access network notification area(RNA)configuration scheme.Firstly,the users are divided into the rate-priority type and the speed-priority type according to paging rate and mobility rate.The optimal RNA will be associated to users according to their properties to reduce the overall signaling overhead.Secondly,the dynamic RNA configuration scheme includes the following two steps: in the offline RNA optimization step,all available RNA lists for users are assigned to generate the optional RNA lists set.In the online decision making step,the optimal RNA list from the offline step will be assigned to users according to their properties.Finally,based on different delay requirements,users are classified into the delay-sensitive user and the delay tolerant user,which use parallel and sequential paging scheme to optimize the total network overhead,respectively.Furthermore,to reduce the inter-cell interference,improve resource utilization and maximize the average energy efficiency of the network,this thesis studies the optimal resource allocation scheme for UEs in 5G SCNs.Firstly,to reduce inter-cell interference,when the inactive user successfully accesses the network through paging,the user-centered virtual cell is established,and the transmission quality is improved with optimal resource allocation.Secondly,considering the user data packet queue length and the channel quality,the energy efficient problem is decomposed into two sub-problems based on Lyapunov optimization method: optimal resource allocation and optimal power allocation.Finally,simulation results verify that the proposed algorithm can maximize the energy efficiency of the network while guaranteeing the system stability.