Technology Research And Analysis Of The Judgment Under Heterogeneous Wireless Network Environment Network Vertical Handoff

Heterogeneous wireless network is an important development trend of future network.Users can make full use of the advantages of different types of network technology, obtain "Always Best Connection, ABC". But these different types of wireless networks are very different in access technologies, coverage, service type, etc. It makes the traditional horizontal handover technique unable to solve the problem of heterogeneous wireless network mobility management. Therefore, the vertical handover technology is a network handover technology for settling the problem of seamless handover of mobile terminals in heterogeneous wireless network.This article studied and designed network vertical handover framework and vertical handover decision algorithm:(1) designed a improved vertical handover framework based on MIH. This framework added a vertical handover management module based on IEEE802.21MIH. Through the framework, we can realize the awareness of the terminal status and the calculation collection and sharing of the network QoS score.(2) designed a Network Prediction and Fuzzy-Logic Based Vertical Handoff Decision Algorithm (NP-FVHD), which is based on terminal control and network assisted. This algorithm calculates the network QoS score for four different types of business respectively, uses GM (1,1) to predict the future network QoS score. And users the speed and the residence time of mobile terminal to do network pre-screening and pre-judgment. Finally, make the network handover decision based on the network real QoS score, predicted QoS score and the battery of mobile terminal. In addition, this paper proposed an improvement suggestion based on QoE.This paper carried out the experiment aimed at the above study:firstly, analyzed the performance of the vertical handover framework. The result shows that this framework can effectively reduce the handover delay and the power consumption of mobile terminals. Then, designed three different kinds of network QoS change simulation scenario to verify the performance of NP-FVHD algorithm. The result shows that the NP-FVHD algorithm can effectively increase the accuracy of the network QoS evaluation and effectively reduce the unnecessary handover. At the same time can reduce the "ping-pong effect" and increase the battery life of the terminal.