Research On Fairness Resources Allocation Algorithm For Multicast In A Heterogeneous Network

With the rapid development of wireless communication technology,in order to adapt the communication environment variability and the growing number of business types,giving users rich wireless multimedia service experience and faster data transfer rates and better quality of service,really satisfy anyone to communicate at any time and any where,heterogeneous networks(Het-Net)has become an inevitable trend in the development of future wireless network.A variety of radio access networks are expected to be heterogeneously integrated,achieve collaborative communication and support user multi-homing transmission and diversity of services in future mobile communication network.In the development of heterogeneous networks,radio resource management is the key technology to resolve the conflicts between growing proliferation of mobile business needs and the extremely scarce radio resources.This paper focuses on the heterogeneous network radio resource management issues,and conduct research on the fairness resources allocation of radio resource management,including the following:First,analyze and summarize the contents and status of research in today's heterogeneous wireless networks and radio resource allocation algorithm.Overview of power allocation,subcarrier allocation and the fairness norms about the radio resource allocation methods.Noted the importance of resource allocation algorithm research.Then,construction bilayer heterogeneous cellular network system model by the macro cell and pico cell according to the actual scene of the cellular network,propose a proportional fairness subcarrier allocation algorithm in heterogeneous network with inter-cell-interference,where the different cells intend to transmit different common message to their served user equipments.The main contribution of this part is to maintain a proportional fairness among cells.Simulation results illustrate that our subcarrier allocation algorithm guarantee a proportional fairness for multicast among the cells in Het-Net and can achieve a better system performance than the conventional algorithm.Finally,the bilayer heterogeneous cellular network system as a system model,formulate the problem to guarantee a max-min fairness for multicast in an orthogonal frequency division multiple access(OFDMA)-based Het-Net by managing the power allocation and subcarrier allocation at base station(BSs)of coexisting macrocell and picocell,where different common messages are,respectively,transmitted from BSs to their served user equipments in the same frequency.We simplify the power allocation to a corresponding Geometric programming(GP)problem,which brings forth a suboptimal power allocation algorithm to guarantee a max-min fairness.Subcarrier allocation is different from the frequency reuse manner in power allocation,the BS of macrocell(MBS)and BSs of picocells(PBSs)to their served user equipments on different subcarriers.Thus,cochannel interference is avoidable for multicast.The proposed subcarrier allocation algorithm is composed of initialization step and greedy step.Initialization step is guaranteed to every cell have at least one subcarrier.The greedy step based on the exhaustive method,which intends to maximize the minimum rate for multicast in the Het Net at each stage of allocating the remaining subcarriers.Simulation results demonstrated that,with the proposed power allocation algorithm and subcarrier allocation algorithm,a higher transmission rate and a larger Jain's fairness index for multicast among cells in a Het-Net can be achieved compared to the previous allocation algorithm.