Multi-dimensional Context-Aware Model In Wireless Heterogeneous Converged Networks

To achieve the goal of ubiquitous information society, the future communication networks will show a variety of features, such as ubiquity, heterogeneity, symmetry, context-awareness and self-organization, self-healing.Context-awareness as the significant feature will be brought into academic and industry .Based on the author's research experience in the NSFC project, the thesis discusses existing international research results on context-aware and proposes multi-dimensional context-aware model in wireless heterogeneous converged networks.Firstly, the wireless heterogeneous converged network architecture, which can extend access network discovery and selection, vertical handover, and content adapation, is presented.Then, according to the research of virtual terminal, the thesis gives the concept of multi-network and multi-terminal cooperation which resolves the problem of providing service based on convergence.In the sophisticated environment of wireless heterogeneous converged network, context information, as the input of context-awareness, runs through the entire transmission channel, which is the hub of controlling user information, terminal information, service information, and network information.Context information presents a series of characteristics, such as diversity, dynamics, and complexity.Thus, the multi-dimensional context-aware model in which context information is divided into accuracy/fuzzy, fast/slow, time/spatial and history/future is given in this paper. And accuracy/fuzzy and fast/slow dimensions are solved respectively by leveraging on fuzzy logic and publish mechanism, using time stamp, two-hierarchy ontology and feedback, predict function to accomplish time /spatial and history/future. To verity its rationality and feasiblity, the thesis takes theory analysis and simulation into account, and the testing results have shown that the multi-dimension of context information can seize the nature of context information, improve control efficiency, and optimize vertical handoff.