Convergence And Handoff In All-IP Wireless Heterogeneous Networks

The future prospect of wireless communication is to establish a public, flexible and seamless heterogeneous network, which is based on IP protocol, and combine different kinds of wireless networks to IP core network. This thesis discussed the mode and structure of heterogeneous network integration, the handoff process, algorithms and all IP mobility management. It especially researched on two aspects: multi-object handoff and seamless mobility management, and finally, proposed realizable schemes.This thesis researched various wireless networks on network architecture, operating model, handoff technology, position management and resource management, and also proposed a smooth scheme for 2G to 3G transition and the internetworking of GSM and CDMA systems. Take GSM, WCDMA, CDMA20001X and WLAN for example, we summarized the tight coupling and loose coupling schemes, and analyzed their differences.Vertical handoff is a key problem in all IP heterogeneous network integration. It deals with different network structure, access technology, and performance evaluation. Obviously, current handoff algorithms can not satisfy such requirement. In this thesis, we redivide the handoff process, emphasized the network selection process. After a conclusion of current handoff algorithm, we proposed a multi-object handoff algorithm based on AHP. AHP is an operational theory, which can make judgment for complex multi-object handoff problem. The algorithm proposed in this thesis can take an overall consideration; calculate more accurate weight of factors through the pairwise comparison matrix. Besides, it provides consistent test method.