【作者】 吕东；

【导师】 张远见； 苏华鸿；

【作者基本信息】 华南理工大学 ， 电子与通信工程， 2009， 硕士

【摘要】 IEEE提出WiMAX无线网络标准,包含了OFDMA、MIMO和SSA等耳目一新的技术,同时在网络架构上,也有其前瞻性的考虑,网络全IP化和扁平化的网络架构,均为通信网络长期演进的方向。WiMAX网络接入服务网关(Access Service Networks Gateway,ASN-GW)是连接基站(Basic Station,BS)和核心网(Connectivity Service Network,CSN)的关键系统,网络中的众多功能由ASN-GW和BS协同完成,例如网络进入、网络退出、MS切换(Handover,HO)、服务流管理(Service flow management,SFM)、DHCP和AAA等,其中切换是WiMAX系统中最关键的流程控制模块之一,目前大量的文献研究均在关注BS的切换工作,对ASN-GW的切换研究与设计工作较少。本文将完成ASN-GW系统切换功能的研究与设计实现,主要工作是遵循WiMAX网络工作组(Network Working Group,NWG)论坛建议,采用面向对象思想和C++语言进行工程实现,并得出有关切换的测试数据。本文首先介绍WiMAX切换研究的状况,然后说明了ASN-GW系统整体架构设计,以及相关的硬件平台和操作系统。重点描述了ASN-GW切换的设计和实现,实施切换工作的时候,切换模块将与系统中的多个功能模块发生交互,比如数据隧道、MS上下文、CMAC等。最后描述了ASN-GW的测试开发和平台搭建,验证了ASN-GW切换的功能和性能,得到的测试指标均满足蜂窝式移动通信运营商的要求。测试是验证切换设计实现的关键步骤,为了达到测试要求,该研究进行了测试软件开发和搭建了模拟测试网络环境。开发了BS Simulator和MS Simulator,完成了切换各个子模块的单元测试,同时也对整个切换模块进行了大量的性能测试,最后得到了理想的测试结果,如ASN-GW的切换高成功率和低切换时延,为WiMAX系统完成切换功能提供了有力保证。更多还原

【Abstract】 With the forthcoming WiMAX wireless network specification, IEEE has covered many new technologies such as OFDMA, MIMO, SSA and so on. Meanwhile, within a framework of IP-based and flat network, it is such a perpsective study that leads the direction of long-term evolution in the communication field.WiMAX is a key system to connect BS and CSN, and most of its functions such as Network Entry, Network Exit , MS, SFM, DHCP, AAA, etc. are done by ASN-GW and BS together. Among them, MS Handover is one of the most crucial flow controlling modes, but up to now most studies only concentrate on BS Handover while there are few researches concerning ASN-GW handover.Taking the current situation into consideration, the present thesis hence mainly focus on the design and realization of ASN-GW Handover. Under the guidance of WiMax NWG principles, it adopts an object-oriented way to realize the whole project by using C++, and in the end some relevant testing data are expected to be obtained. At the beginning, the thesis introduces the background of WiMAX Handover, then explains the hardware platform and whole framework of WiMAX Network, and later puts the emphasis on its design and realization. Finally, the network development and platform construction of ASN-GW being described in detail efficiently confirms the function and performance of ASN-GW. It can be concluded that all the testing parameters could satisfy the needs of telecom service providers.Testing is a strategic point in the process of Handover design and realization. To meet the requirment, the present study develops BS Simulator and MS Simulator to operate the whole testing process in which each sub-module and correspondent funtions are fully tested. The testing result has proved to be satisfactory: the high successful ratio and low time-delay of ASN-GW handover will provide powerful assistance to the handover function of WiMAX network system.更多还原