Research On Resource Allocatio Startegy Under 5G Multi-connectiviy

With the development of mobile communication,the Fifth Generation Mobile Communication(5G)system has been proposed.The applications involved in 5G can be divided into three major scenarios,namely Enhanced Mobility Broadband(eMBB),Massive Machine Type Communication(mMTC),Ultra-Reliable and Low Latency Communications(URLLC).These three service scenarios contain all of the new network applications such as high-definition video,V2X,and virtual reality,which have more stringent requirements for network in terms of transmission rate,latency,throughput,and reliability.Multi-connectivity is a key technology for 5G networking,which can be used to realize the diverse scenarios and requirements.Under 5G multi-connectivity,users can utilize resources from multiple cells simultaneously,thus reducing transmission latency,improving transmission rate as and network throughput.Besides,diversity can be realized through multiple transmissions,thus improving the transmission reliability.Therefore,we make a research on resource allocation strategy under 5G multi-connectivity for different service scenarios and quality of service(QoS)requirements based on the applications of multi-connectivity in improving network performance.The main contents of this thesis can be seen as the following:Firstly,this thesis makes researches on traffic splitting strategy which optimize network throughput under multi-connectivity based on the application of 5G multi-connectivity in improving transmission rate and network throughput.It mainly includes the modeling of traffic splitting problem under multi-connectivity as well as traffic splitting optimization.M/D/1 queuing theory and goodput is used to model the traffic splitting problem under multi-connectivity.Based on this,we propose a traffic splitting optimization problem under multi-connectivity.convex optimization is used to solve this problem and obtain a traffic splitting strategy to optimize network throughput under multi-connectivity.Simulation results show that the traffic splitting strategy proposed in this thesis can achieve matches of traffic and network capabilities by dynamically splitting traffic,thus maximizing network throughput.Secondly,based on the application of multi-connectivity in improving the transmission reliability,this thesis makes research on resource allocation strategy with QoS guarantee of URLLC under multi-connectivity.In this thesis,we propose a dynamic packet duplication transmission scheme for URLLC service under multi-connectivity,which can not only improve the transmission reliability of URLLC,but also reduce the required wireless resources to guarantee QoS of URLLC,thus improving the resources utilization ratio.Considering of the short packet transmissions of URLLC,we use effective bandwidth(EB)and finite block length(FBL)to analyze and model URLLC and its' QoS.Based on this,we propose a resource allocation optimization problem with QoS guarantee of URLLC under the proposed multi-connectivity packet duplication scheme.The proposed optimization problem can be divided into a frequency and power resource allocation problem as well as a packet duplication transmission strategy optimization problem which can be solved iteratively.Simulation results show that the proposed resource allocation strategy with QoS guarantee of URLLC under multi-connectivity can optimize the required bandwidth resource while guarantee the QoS requirement of URLLC.Finally,this thesis makes a research on resource allocation strategies for hybrid services across eMBB and URLLC under multi-connectivity.In this thesis,we adopt different dimensions of scheduling slots and priority for eMBB and URLLC.To ensure the high reliability requirements of URLLC,we use the dynamic packet duplication scheme proposed previously in this thesis.Moreover,to reduce the impact of URLLC on eMBB and improve the transmission rate of eMBB,we introduce multi-connectivity for eMBB service.Simulation results prove that the proposed hybrid service resource allocation strategy across eMBB and URLLC under multi-connectivity can maximize the transmission rate of eMBB while guarantee the reliability and latency requirement of URLLC.