2g___3g___4g移动通信系统物理层演进大学生毕业论文（设计）.doc

毕业设计（论文） 设计（论文）题目：  摘 要 中国当前的TD-SCDMA商业在实现TD-SCDMA技术中出现了很多的问题，包括其市场和其在各方面的应用。为了使TD-SCDMA技术成熟，从当前的TD-SCDMA标准升级到IMT-Advanced（高级国际移动通信）标准是大家热切期盼的。针对得到一个到下一代移动通信系统的平滑过渡，TD-SCDMA标准和技术将要走上一条国产的、自主的革新之路。本文为TD-SCDMA标准和关键技术的革新策略提供一个简短的描述调查TD-SCDMA发展到至今水平的革新史，发现它在不同的革新阶段的技术及标准都各有特点。单/多载波、高速数据包存取以保证数据包服务的高传送率是第一革新阶段的特点，同时，广播服务也被支持，HSPA(High Speed Packet Access 高速分组接入)也被并入到这次革新。“长期革新”在为了接近全球微波互操作性性能的第二阶段被定义。在第二阶段中基于相互作用通道的多重天线被采用。最后一个阶段是基于TD-LTE 的从传统3G系统到超越传统系统的IMT-Advanced（高级国际移动通信）系统的革新。3GPP （3rd Generation Partnership Project第三代合作伙伴计划）的 标准与本地标准的不同将被放出并介绍一些各个革新阶段的挑战性的工作和开发性的问题同样也会被拿出来讨论。 【关键词】全球移动通信系统  ABSTRACT The current TD-SCDMA commercialization in China brings about many issues concerning the implementation of TD-SCDMA technology,the market, and its applications. In order to make TD-SCDMA successful, evolution from the current TD-SCDMA standards to International Mobile Telecommunications-Advanced are anticipated. TD-SCDMA standards and technologies will take a home-made evolution path in China, aiming at a smooth migration to the next-generation mobile communication system. This article provides a brief description of the evolution strategies of both the standards and key technologies, in which the evolution is divided into three phases. The state of the art of TD-SCDMA evolution is surveyed, and its technologies and standards in different evolution phases are characterized. Single- and multi-carrier high-speed packet access is specified in the first evolution phase for guaranteeing the high transmission bit rate of packet services. Mean-while, broadcast services are supported, and the HSPA evolution is also incorporated in this phase. Long Term Evolution is defined in the second evolution phase for approaching similar performance as mobile WiMAX, where channel-reciprocity-based multiple antenna techniques are utilized. The last phase is the revolution to the IMT-Advanced system and becoming one alternative standard in beyond 3G systems,which is based on the evolu