The Research on the Vertical Handoff Algorithms in Heterogeneous Wireless Networks
|School||Huazhong University of Science and Technology|
|Course||Signal and Information Processing|
|Keywords||Heterogeneous wireless networks Vertical handover Multi-service LTE WLAN|
Switching technology is one of the core technology of the wireless network is to ensure that users achieve seamless roaming key. To isomerization in the future as the main features in the wireless network environment, including not only the level of switching between the traditional access techniques on the same network, further comprising a vertical handover between different network access technology. Essentially vertical switch and level switch is very different, and have higher performance requirements, has always been a heterogeneous network switching technology research focus. Major national projects: the new IMT-Advanced radio resource management and verification \Firstly, the paper from the vertical handover procedure, vertical handoff performance requirements, vertical handover algorithm right vertical switch technology was elaborated, the focus of the following typical vertical handover decision algorithm: Based on the received signal strength, based on the objective function, based on multi-objective decision-making based on fuzzy logic and neural networks, and context-based perception. Second, for multi-service network selection in the the existing collective business network selection algorithm based on business priority network selection algorithm based on the comprehensive advantages of these two algorithms proposed an improved multi-service network selection algorithm, the The algorithm uses the collective business network selection algorithm thought, at the same time set a priority to a business user. Application examples: Improved multi-service network selection algorithm, based on no increase in complexity algorithm to calculate both the advantages of the existing algorithms, not only to meet the user's requirements on business priorities, and successfully avoid the priority network-based business Select the algorithm in a business alone dropped the case. Finally, LTE and WLAN integration of heterogeneous networks, the paper proposes a vertical handover strategy based on user rate. Achieve the policy in two steps: first, according to the user's mobile rate the initial handover decision; In this paper, the use of improved multi-service network selection algorithm to select the most appropriate for the user to switch the target network. Simulation results show that: the vertical handover policy based on user rate to meet the requirements of the user rate and business priorities, the pros and cons of LTE and WLAN networks complement each other, can bring greater satisfaction to the user. Of this research work on the realization of the user in the future heterogeneous network environments smooth handoff seamless roaming important theoretical significance, some positive effects to improve the core competitiveness of the national communications industry.