Research On Call Admission Control Mechanism Of Heterogeneous Wireless Network

With the evolution of cellular communication systems (2G/3G/LTE) and the fast development of multiple wireless broadband access technologies (WLAN/WiMAX/WiFi),it can be foreseen that the future mobile communication scenario will be All-IP heterogeneous network environment with multiple radio access technologies.This paper conducts research on key technologies of UMTS,WLAN and WiMAX network convergence. These systems are briefly described. Advantages respectively and the necessity of inter-working and convergence addressed.Research on the two forms of the integration of heterogeneous network and tight coupling is chosen to be the research base of call admission contro.By research on the heterogeneous network mobility management, heterogeneous network environment based on HMIPv6 is chosen to be the research base.This paper conducts a novel hierarchical joint call admission control (HJCAC) concept, including network model in UMTS-WLAN tight coupling, signaling flow, work scenario, architecture design, and policy-based cooperative network selection algorithm.HJCAC model is designed and implemented on UMTS-WLAN interworking NS2 simulation platform, in order to simulate and evaluate HJCAC management strategy. The results show that HJCAC strategy can help terminal access the most suitable network according to network, service and user information.As access rate increases 3%,it can help to achieve load balancing and optimize network resource allocation. In wireless communications,how to reduce the power consumption of terminal equipment with limited energy has become a major research topic.This paper conducts research on sleep mode of IEEE 802.16e standard in heterogeneous network. And then it adjusts the sleep parameters to achieve the purpose of energy-efficient according to different types of data traffic.Sleep mode model is designed and implemented on NS2 simulation platform, in order to simulate and evaluate sleep mode management strategy. It proves that power loss is reduced when there is no data transmission and improves the efficiency in the use of air resources.At last, this paper summarizes the results achieved, prospects the development of multiple radio access technologies in the future wireless mobile communication and gives some recommendations for further depth research.