无线异构网络的垂直切换算法研究

以通用移动通信系统(UMTS)与无线局域网(WLAN)融合为例,研究无线异构网络的垂直切换算法。由于垂直切换算法应考虑因素的复杂性以及不同网络性能的各异性,有必要对现有算法作出归纳总结比较,并据此提出新的垂直切换算法。该算法以代价函数为基础,将稳定周期与切换目标网络和当前服务网络的效用函数联系起来,实现移动节点自适应的切换判决。提出的算法能有效减少不必要的切换,增强异构网络的适应性。

Study of Vertical Handoff Algorithm for Heterogeneous Wireless Networks

With the convergence of UMTS （Universal Mobile Telecommunications System） and WLAN （Wireless Local Area Network） as an example, the vertical handoff algorithm for heterogeneous network is studied. For the reason that the complicated factors need to be considered in handoff algorithm and the diversified network performances, it is necessary to make summing-up and comparison of the existing handoff algorithms, and thus to propose a new algorithm. This new algorithm, based on the cost function and by establishing the tight relationship between stable periods and utility function connecting the target network and the current network, could achieve adaptive handoff decision of the mobile node. The experiment shows that this new algorithm could effectively decrease the unnecessary handoffs while improve the adaptability of heterogeneous network.