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1、南京邮电大学研究生专业英语翻译 刘旭老师 2017 年第一学期 注 译文仅供参考注 译文仅供参考 1 Analog cellular systems are commonly referred to as fi rst generation systems The digital systems such as Global System for Mobile Communications GSM PDC cdmaOne IS 95 and US TDMA IS 136 are second generation systems 模拟蜂窝系统通常被称为第一代系统 数字系统 如全球移动通信系统
2、GSM PDC cdmaOne IS 95 和 US TDMA IS 136 的是第二代系统 These systems have enabled voice communications to go wireless in many of the leading markets and customers are also increasingly fi nding value in other services such as text messaging and internet access which are starting to grow rapidly 使用这些系统 客户 可以
3、通过无线的方式进行语音通信 在市场中占据了主导地位 客户在使用的过程中还不断地挖掘出一些其他的有价值的服务 如文本信息传送 因特 网接入 这些服务开始迅速发展起来 2 Third generation systems are designed for multimedia communication with these person to person communication can be enhanced with high quality images and video and access to information and services on public and pri
4、vate networks will be enhanced by the higher data rates and new fl exible communication capabilities of third generation systems 第三代移动通信是为多媒体通信所设计的 使用这样一个系统 人与人之间的通信可以 增强为高质量的图像和视频传送 第三代移动通信的高速数据传输能力和灵活的通信能 力可以有效地增强公共网络和私有 专用 网络的信息和服务 This together with the continuing evolution of the second generat
5、ion systems will create new business opportunities not only for manufacturers and operators but also for the providers of content and applications using these networks 与不断演进的第二代移动通信一起 这些发展不仅为制造商和运营商 同时也为使用这 些网络提供内容和应用的商家提供了新的商机 3 In the standardization forums Wideband Code Division Multiple Access W
6、CDMA technology has emerged as the most widely adopted third generation air interface 在标准化论坛中 宽带码分多址 WCDMA 技术成为最广泛的第三代移动通信空中接 口 Its specification has been created in the 3rd Generation Partnership Project 3GPP which is the joint standardization project of the standardization bodies from Europe Japan
7、 Korea the USA and China 其规范由第三代 移动通信 合作组织 3GPP 制定 3GPP 是由欧洲 日本 韩国 美国和中国的标准化组织构成的联合标准化项目 Within 3GPP WCDMA is called Universal Terrestrial Radio Access UTRA Frequency Division Duplex FDD and Time Division Duplex TDD the term WCDMA being used to cover both FDD and TDD operations 在 3GPP 中 WCDMA 被称为全球陆
8、地无线接入频分双工 FDD 和时分双工 TDD 术语 WCDMA 在使用中是指同时包括频分双工 FDD 和时分双工 TDD 的运行方式 4 Work to develop third generation mobile systems started when the World Administrative Radio Conference WARC of the International Telecommunications Union ITU at its 1992 meeting identified the frequencies around 2GHz that were ava
9、ilable for use by future International Mobile Telephony 2000 IMT 2000 mobile systems both terrestrial and satellite 国际电信联盟在 1992 年的世界无线电管理大会上确定 在陆地上和卫星上 未来的国 际移动电话 2000 系统 IMT 2000 均可以使用 2GHz 频段 自此 第三代移动通信系统 的开发工作正式启动 Within the IMT 2000 framework five air interfaces are defined for third generation
10、 systems based on either CDMA or TDMA technology 基于码分多址和时分多址技术 IMT 2000 框架体系为第三代系统定义了五种空中接口 5 The original target of the third generation process was a single global IMT 2000 air interface In practice the third generation systems are closer to this target than were second generation systems since WC
11、DMA has clearly turned out to be the most dominant IMT 2000 standard in commercial deployments 第三代系统最初的目标是建立一个统一的全球IMT 2000空中接口 实际上 由于WCDMA 在 IMT 2000 标准的商用部署中已占据了主导地位 第三代系统比第二代系统更接近于 这个目标 The same WCDMA air interface is deployed in Europe Asia Australia in North and South America and in Africa 在欧洲
12、亚洲 澳大利亚 北美和南美以及非洲部署了相同的 WCDMA 空中接口 6 Most of the WCDMA deployments use the identified IMT 2000 spectrum around 2 GHz 1920 1980 MHz for uplink and 2110 2170 MHz for downlink This spectrum is in IMT 2000 use in Europe Asia including Japan and Korea and in Brazil 大部分的 WCDMA 部署在 IMT 2000 的 2GHz 的频谱附近 即
13、1920 1980 MHz 上行链路和 2110 2170 MHz 下行链路 这部分的频谱是欧洲 亚洲 包括日本和韩国 和巴西的 IMT 2000 中使用 The first licenses for that spectrum were granted in Finland in March 1999 followed by Spain in March 2000 No auction was conducted in Finland or in Spain Also Sweden granted the licenses without auction in December 2000 1
14、999 年 3 月 芬兰率先派发了第一张该段频谱的牌照 2000 年西班牙颁布了该牌照 当时 无论是芬兰还是西班牙都没有对牌照进行拍卖 同样 瑞典在 2000 年 12 月颁发 牌照时也没有进行拍卖 However in other countries such as the UK Germany and Italy an auction similar to the US personal Communication System PCS spectrum auctions was conducted 但是 其他一些国家 比如英国 德国和意大利对频谱进行了拍卖 这月当年美国的个 人通信系统
15、PCS 频谱拍卖过程很类似 7 WCDMA will also be deployed in the existing second generation frequency bands that were also identified for IMT 2000 in WRC 2000 and are currently used by GSM or CDMA That approach is called refarming WCDMA 同样可以在第二代通信系统现有的频段中部署运行 这些频带是 WRC 2000 会 议上为 IMT 2000 确定 目前用于 GSM 和 CDMA 这种演进方
16、式叫做 重整 The WCDMA deployment in the USA started by refarming WCDMA to the existing cellular bands at 850 MHz and to the PCS band at 1900 MHz since there were no new frequencies available for WCDMA deployment WCDMA 开始在美国部署时 由于美国当时没有新的频带可供 WCDMA 使用 因此当时 美国的 WCDMA 部署是对现存的 850MHzd 的蜂窝频带和 1900MHz 的个人通信业务频带 进行重整 8 A new frequency band was auctioned in the USA in 2006 This band the so called Advanced Wireless Services AWS band is located at 1700 MHz for uplink and at 2100MHz for downlink WCDMA deploymen
