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通信专业英语大作业姓 名: 罗强 学 号: 201230105089 序 号: 01号 系 别: 中兴通信工程学院 班 级: 12级通信六班 完成时间: 2014、12、26 一、 翻译4G Mobile:4G MobileVoice was the driver for second-generation mobile and has been a considerable success.Today,video and TV services are driving forward third generation (3G) deployment. And in the future, low cost, high speed will drive forward the fourth generation (4G) as short-range communication emerges. Service and a plication ubiquity,with a high degree personalization and synchronization between various user appliances, will be another driver. At the same time, it is probable that the radio access network will evolve from a centralized architecture to a distributed one.声音是第二代移动驱动,并得到了相当大的成功。今天,视频和TV服务正在向第三代(3G)发展。并且在以后,低成本和高速的特点将带动它们进入第四代(4G)即短距离通信,随着服务和折叠技术的普及,各种用户设备之间的个性化和同步化程度越高,将成为另一个驱动器。在同一时间,该无线电接入网络有可能将来自集中式架构演进到一个分布式之一。1 .Service EvolutionThe evolution from 3G to 4G will be driven by services that offer better quality(e.g.,video and sound) thanks to greater bandwidth, more sophistication in the association of a large quantity of information, and improved personalization. Convergence with other network (enterprise,fixed) services will come about through the high session data rate. It will require an always-on connection and a revenue model based on a fixed monthly fee. The impact on network capacity is expected to be significant. Machine-to-machine transmission will involve two basic equipment types: sensor (which measure parameters)and tags (which are generally read/write equipment).It is expected that users will require high data rates,similar to those on fixed networks,for data and streaming applications. Mobile terminal usage (laptops, personal digital assistants, handhelds) is expected to grow rapidly as they become more user friendly. Fluid high quality video and network reactivity are important user requirements. Key infrastructure design requirements include: fast response, high session rate, high capacity, low user charges, rapid return on investment for operators, investment that is line with the growth in demand, and simple autonomous terminals.The infrastructure will be much more distributed than in current deployments, facilitating the introduction of a new source of local traffic: machine-to-machine.1服务革命从3G到4G演进将由更高质的服务(例如,视频和声音)推动,更大的带宽使得大量信息的关联显得更加复杂,个人化也得到了提高。要想融合了其他网络(企业,固定的)服务的出现得通过高会话的数据速率。这将需要一个永远在线的连接,并收取固定的月租费。预计这对网络容量的影响是显著。机器间的传输将涉及两个基本类型的设备:传感器(用来测量参数)和标签(通常用来读/写设备)。据估计,用户会需要高数据速率,类似于那些在固定网络提供数据和数据流的应用程序。移动终端的使用(笔记本电脑,个人数字助理,掌上电脑)有望迅速增长,因为它们变得更加方便用户。流畅高质的的视频和网络的反应性是重要的用户需求。关键基础设施的设计要求包括:快速响应,高会话率,高容量,低使用费,运营商投资的快速回报。投资能够按照需求的增长,以及简单的自发终端。基础设施将比目前的部署更加分散,这样便于引进本地通话的新来源:机器对机器。2 .Multi-technology Approach Many technologies are competing on the road to 4Q,as can be seen in Figure 1.Three paths are possible, even if they are more or less specialized. The first is the 3G-centric path, in which Code Division Multiple Access (CDMA) will be progressively pushed to the point at which terminal manufacturers will give up. When this point is reached, another technology will be needed to realize the required increases in capacity and data rates. The second path is the radio LAN one. Widespread deployment of WiFi is expected to start in 2005 for PCs, laptops and PDAs. In enterprises, voice may start to be carried by Voice over Wireless LAN (VoWLAN). However, it is not clear what the next successful technology will be. Reaching a consensus on a 200 Mbit/s (and more) technology will be a lengthy task, with too many proprietary solutions on offer. A third path is IEEE 802.16e and 802.20, which are simpler than 3G for the equivalentperformance. A core network evolution towards a broadband Next Generation Network (NGN) will facilitate the introduction of new access network technologies through standard access gateways,based on ETSI-TISPAN, ITU-T, 3GPP, China Communication Standards Association (CCSA) and other standards. How can an operator provide a large number of users with high session data rates using itsexisting infrastructure? At least two technologies are needed. The first (called parent coverage) is dedicated to large coverage and real-time services. Legacy technologies, such as 2G/3G and their evolutions will be complemented by WiFi and WiMAX. A second set of technologies is needed to increase capacity, and can be designed without any constraint on coverage continuity. This is known as pico-cell coverage. Only the use of both technologies can achieve both targets.Handover between parent coverage and pico cell coverage is different from a classical roaming process, but similar to coverage handover.Parent cover can also be used as a back-up when service delivery in the pico cell become too difficult.2多技术方法如在图1可以看出,许多技术都在4Q的道路上争夺着,.有三种路径是可能的,即使它们或多或少专门化。第一种路径是3G中心,其中码分多址(CDMA)将逐步被推到终端制
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