此程序为发表过的一篇IEEE PIMRC 的paper的程序代码。是关于异构无线网络环境下的垂直切换接口激活时间的几个方案的仿真性能比较。-This RAR package contains a set of program code which was used in a　published paper on in IEEE PIMRC. It is about the interface activition time in heterogeneous wireless networks.