一种新的异构无线接入网垂直切换方法

为了提高异构无线网络中垂直切换的准确度、减少连接掉线,提出了一种新的垂直切换方法.该方法改进了基于RSS的切换触发机制,并且采用基于模糊逻辑的归一化量化决策算法,从可用的接入网中选择最优的切换目标网络.为验证方法的可行性,采用由UMTS和WLAN构成的仿真场景.仿真结果表明,提出的方法通过平衡用户的偏好、网络状态和系统性能,有效地选择了最优的网络;同时,在垂直切换次数和切换掉话率方面优于其他方法.

A New Vertical Handoff Method for Heterogeneous Wireless Access Networks

In order to improve accuracy of vertical handoff and to decrease connection dropping in heterogeneous wireless networks,a vertical handoff scheme was presented.This scheme improves the RSS-based handoff trigger mechanism and adopts the fuzzy logic-based normalized quantitative decision algorithm to determine the optimal handoff target network from all available access networks.To verify the feasibility of this approach,a heterogeneous network comprising UMTS and WLAN was used in simulation.Numerical results have demonstrated that the proposed approach outperforms other ones in the number of vertical handoff and handoff dropping rate while choosing effectively the optimum network by making trade-off among the user preference,network condition and system performance.