基于GSM/GPRS的A-GPS定位终端软件中主控模块的设计与实现

【作者】 杨彬；

【导师】 武穆清；

【作者基本信息】 北京邮电大学 ， 通信与信息系统， 2007， 硕士

【摘要】 全球定位系统(Global Positioning System，缩写GPS)，是美国第二代卫星导航系统，是在子午仪卫星导航系统的基础上发展起来的，它采纳了子午仪系统的成功经验。和子午仪系统一样，GPS由空间部分、地面监控部分和用户接收机三大部分组成。以前在国内GPS主要应用于铁路、空运及海运领域。近年，随着GPS技术和嵌入式技术的日臻成熟，GPS车载定位终端开始出现，并且有着广阔的市场前景。本文第一部分“基于GSM/GPRS的A-GPS定位终端软件中主控模块的设计和实现”是基于作者在研究生期间就GPS车载定位终端所做的一些研发工作而展开的。在此部分中，作者深入学习了GPS和GSM/GPRS等理论知识，同时结合嵌入式软件的开发特点和流程，完成了定位终端软件的系统设计、接口设计以及主控模块的详细设计、测试设计，并实现了主控模块的功能。Ad hoc无线网络是一种移动通信和计算机网络相结合的网络，它可以广泛地应用于战场通信指挥与控制、警察与医疗部门的抢险救灾、传感器网络、课堂教育等众多领域，其战略意义非常重要。MPLS(Multiprotocol Label Switching，多协议标签交换)技术是一种在开放的通信网络上利用定长标签引导数据高速传输和交换的网络新技术。MPLS采用最简化的技术来完成第三层交换向第二层交换的转换。它在IP数据包前加入固定长度的包头(标签)，不对IP数据包的内容做任何的处理。采用固定长度的标签，加快了MPLS交换机查找路由表的速度，减轻了交换机的负担。本文第二部分“基于标签交换的Ad hoc无线网络仿真中AODV进程模块的设计与实现”是基于作者在研究生期间就Ad hoc网络和MPLS技术所做的一些研究工作而展开的。在此部分中，作者详细地了解了国内外Ad hoc网络的研究现状，深入研究了Ad hoc网络的特点，在Ad hoc路由协议AODV的基础上结合了MPLS技术的核心思想——标签交换技术，并基于OPNET网络仿真平台实现了基于标签交换的Ad hoc网络仿真模型。更多还原

【Abstract】 GPS which is the second generation satellite navigation systems of the United States, was developed on the basis of Meridian NG. It adopted successful experience of Meridian System. GPS consists of the space segment, the ground control segment and user receiver. GPS was applied to railway, airlift and ocean shipping widely in the past. In recent years, with the development of GPS and embedded technology, the Vehicle-carry systems of GPS appeared and would have great market.In this dissertation, the first part of "the design and implementation of CORE module in GPS locating terminal software based on GSM/GPRS Network" based on my research and development about GPS. In the part, I accomplished system design, interface design and the implementation of CORE module on the locating terminal software combined with the characteristic and flow of embedded software development.Ad hoc wireless network is a combination of mobile communication networks and computer networks. It can be widely applied to a battlefield communications command and control, rescue of police and medical departments, sensor networks, classroom education and many other fields. It has a very important strategic significance.MPLS is new network technology which used a long-label to lead data high-speed transmission and exchange in an opening communications network. MPLS implement transition of switching from Layer 3 to Layer 2. It adds a fixed length of label to the position in front of IP packet, and doesn’t need to do any processing. The use of fixed-length labels accelerates the finding rate of routing table and reduces the burden on the switches.In this dissertation, the second part of "the design and implementation of AODV module in the Ad hoc wireless network simulation based on label switching" based on my research about Ad hoc and MPLS. In the part, I knew the domestic and overseas status detailedly, studied the characteristics of Ad hoc network and combined AODV which is an Ad hoc routing protocol with label switching which is the core idea of MPLS.更多还原