Channel Allocation And Vertical Handover Algorithm On Heterogeneous Network Research

The development of future mobile communication system is not to build a brand newnetwork with all sorts of perfecting functions, but we can keep the continuity of communicationamong in a variety of wireless networks. In order to achieve the goal, it requires the coordinationof the wireless networks. This coordination mechanism involves the seamless switching betweenheterogeneous wireless network technology and resource management technology onheterogeneous wireless environment.First, this paper introduces the development of wireless access technologies, and analyzesthe current problems and hot spot in the relative research on the heterogeneous wireless networks.Then we study the fixed channel allocation (FCA)、 dynamic channel allocation (DCA) andhybrid channel allocation (HCA).On the basis of the research on the dynamic channel allocationstrategy，we research the dynamic channel allocation strategy which has the function ofborrowing others channels. The simulation results show that dynamic channel allocation strategybased on channel borrowing has obvious advantages over others, and it can improve systemcapacity and reduce system block.Then, this paper proposed a switching algorithm in heterogeneous network based ondistinguishing the mobile service and channel allocation. The algorithm is divided into two parts:Terminal access selection and the network channel allocation. The network selection algorithmselect network according to the different preferences of service, then we have the dynamicchannel allocation algorithm to distribute the channel resource which based on the priorities.Based on the different preference on service, network selection and channel allocation have theadvantage to allocate the channel resource according to the personalized needs of users anddifferent service demands for network bandwidth. Voice service has the priority in allocating theWLAN channel resources. Big data service has high priority, and it easily choose to WLANnetwork. The simulation analysis shows that this vertical handoff algorithm can choose thenetwork and allocate channel resource according to the type of the service, and the users havelower blocking rate, the system has larger throughputs.Finally, this paper proposed a network selection algorithm based on classification of service.It concludes two parts: We adopted the analytic hierarchy process (AHP) to analyze the relative importance of the QoS parameters, and then obtain the weight vector of the QoS parameters ofeach type services. Then we use TOPSIS to get the order of the judgment matrix, and select themost suitable network as the targeted network. When the user connects to the network, it isallocated channel resource by its level. The advantages of the algorithm are that we can choosethe most suitable network according to different types of services. The simulation analysis showsthat the proposed algorithm can not only guarantee the QoS of the service, but can improve theutilization efficiency of heterogeneous network resources.