Research On Radio Resource Management Algorithm In Cellular Heterogeneous Heterogeneous Networks

In recent years,with the rapid development of mobile communication technologies,various mobile access services experienced fast growth and are broadly applied,which pose higher requirement on the service providing capability of traditional cellular systems.In order to improve the throughput and network performance and reduce the energy consumption of both networks and devices,the concept of cellular heterogeneous networks(HetNets)which are composed of low power small cells and macrocells has been proposed.However,the irregular deployment of small cells,the intra-cell and inter-cell interference and the diversity of user service requirements pose challenges to the radio resource management of HetNets.In this thesis,the radio resource management algorithms for cellular HetNets are studied,and the main contents are as follows:Firstly,the research background,the architecture and characteristics of cellular HetNets are introduced.Then,the key technologies of radio resource management of cellular Het Nets are elaborated.Specially,this thesis will focus on the resource allocation technologies.The bandwidth allocation algorithms,power allocation algorithms and joint bandwidth and power allocation algorithms for cellular HetNets are summarized and analyzed,emphasizing the importance of joint resource allocation algorithms.For the HetNets composed of one macrocell base station(MBS)and multiple femtocell base stations(FBSs),a joint bandwidth and power allocation algorithm for cellular HetNets is proposed taking into account the resource characteristics and the user quality of service(QoS)of user equipments.Firstly,according to the QoS requirements for femtocell user equipments(FUEs)and macrocell user equipment(MUE)and the existing bandwidth resources of the networks,bandwidth allocation strategies are proposed for FBSs.Particularly,in the case of limited bandwidth resources,the bankruptcy game model is introduced and bandwidth resources are allocated by using Shaply value method.Based on the bandwidth allocation strategy,the power allocation strategy for FBSs is modeled as a multi-objective optimization problem which aims at achieving the maximum energy efficiency of the FBSs.In this thesis,the ideal point method is used to solve the formulated optimization problem,soas to obtain the optimal power allocation strategy of the FBSs.The simulation results demonstrate the performance of the FBSs is improved via MATLAB.For the HetNets,applying non-orthogonal multiple access(NOMA),a joint resource allocation and user association algorithm is proposed.Considering a HetNet composed of one MBS and a number of FBSs,and assuming that orthogonal frequency access schemes are applied to different networks,and NOMA schemes are applied within each network.Joint bandwidth allocation and power allocation and user association problem is formulated as an optimization problem which achieved the maximum throughput for the networks.Then,the optimization problem is transformed into two subproblems,i.e.,resource allocation subproblem and user association subproblem,respectively.After obtaining the optimal transmit power and bandwidth,user association strategy can be obtained to achieve the maximum network transmission rate by solving the user association subproblem.The proposed algorithms are validated that the throughput of the networks is optimized via MATLAB.