摘要
为了实现LTE系统提出的"永远在线"的目的,开机附着(ATTACH)过程中必须伴随分组数据网(Packet Data Net-work,PDN)的连接建立过程,其实质就是默认承载建立过程。对LTE协议栈非接入层总体架构进行介绍;对ATTACH过程中PDN连接过程进行研究,提出了一种PDN连接建立的设计方法,该设计方法避免了资源浪费,实现了LTE终端在开机过程和出现异常时EMM模块和ESM模块间交互流程的统一。并用规范描述语言(Specification and Description Language,SDL)/树表结合表示法(Tree and Tabular Combined Notation,TTCN)对PDN连接建立过程设计进行了测试仿真,结果显示此设计完全符合LTE标准。
In order to enable always-on IP connectivity to the UE, the UE shall send the ATTACH procedure with PDN connection establishment, which is a default EPS bearer established procedure. In this paper, the LTE protocol stack structure of NAS level is described, the ATTACH procedure with PDN connection procedure is researched, and a method related the design of PDN connection establishment is put forward. This design avoids wasting of resources, and LTE terminal start process with appear unusual time EMM module with ESM intermodule mutual flow unified. PDN connection establishment procedure are tested and simulated through SDL/TTCN, and the results show this design in full compliance with the LTE standard.
出处
《电视技术》
北大核心
2012年第19期105-107,共3页
Video Engineering
基金
国家科技重大专项(2011ZX03001-001-02
发改办高技[2010]1634号)
