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《ADSL/VDSL原理(翻译版)》 该书是一本系统介绍ADSL/VDSL原理的教材,从ADSL/VDSL的基本原理入手, 对ADSL/VDSL的发展前景、技术特性、运行环境以及ADSL/VDSL在WAN中的具体应用作了深入浅出的阐述。第一章介绍了ADSL技术的入门与发展背景;第二章至第五章介绍了ADSL技术的运行环境和基本通信概念,包括双绞线环境、环路分析、功率谱密度和串音模型、串音环境下DSL的理论容量;第六章和第七章则分别介绍了DSL 技术的调制基础以及ADSL的调制规范;第八章从实用角度介… 相似文献
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大容量电信级xDSL宽带IP接入设备———Hammer10000IPDSLAMADSL/VDSL与传统的IPDSLAM设备相比具有以下优势。(1)采用纯以太网内核技术 ,支持ADSL组播Hammer10000IPDSLAM采用专利技术在ADSL接口板上完全终结ATM特性 ,并采用以太网交换架构 ,具有30G的背板带宽和全线速L2/L3交换能力 ,保证所有端口具有线速转发能力 ,更重要的是解决了困扰已久的在AD SL线路上难以开展宽带视频组播业务的难题。同时 ,在线路调制方式上遵循ADSL国际标准 ,能与目前市场… 相似文献
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接入技术-ADSL技术的现在和未来发展趋势 总被引:1,自引:0,他引:1
本文论述了ADSL技术的产生背景,而后介绍了ADSL系统的体系结构和AD-SL几种常见的信道分割和调制技术,最后对ADSL技术的前景进行了展望。 相似文献
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简要介绍ADSL宽带接入技术,对ADSL采用的两种不同调制技术CAP和DMT进行了比较;讨论在ADSL设备选型中应注意的几个方面,最后提出以ATM作为骨干网,ADSL作为宽带接入的网络解决方案。 相似文献
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本文介绍了非对称数字用户线路(ADSL)引入的背景,说明充分利用现有用户铅缆资源传递宽带业务的必要性,着重介绍了ADSL的传输技术、结构和功能,及ADSL可能提供的业务和它所具有的特性,并论述了ADSL的应用前景。 相似文献
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ADSL接入技术已成为终端用户最主要的宽带接入技术.ADSL技MODEM.ADSL用户端调制解调器驱动器是一个宽频带功率放大器,他能不失真放大和传输电话线上已编码的数字信号.本文通过对ADSL调制解调器驱动器特点、结构和性能的分析,给出了一种ADSL用户端MODEM驱动器的实现电路.该电路采用具有优良高频的双功率放大器LT1886,即使在配置高电平的闭环增益网络后也能保持较低的失真. 相似文献
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The Internet has surfaced as the dominant early market for residential broadband. ADSL, a transmission system capable of realizing rates from 1 to Mb/s over existing telephone lines, fits Internet access requirements perfectly, and offers telephone companies a tool for connecting virtually all Internet users at megabit rates before the next century. ADSL is asymmetric-high-speed downstream, lower-speed upstream-to counteract speed limitations imposed by line length and crosstalk. The transmission technology itself has two essential forms, single-carrier and multicarrier, which must press Shannon's limit to squeeze so many bits through so little bandwidth. With complicated line coding and other features such as integral forward error correction and ATM/Ethernet mode interfaces, ADSL will be the most complex modem ever attached to a telephone line. This will not prevent ADSL from reaching consumer-level pricing within the next two years. We can expect some commercial deployment in 1997 and virtually ubiquitous availability by the end of 1999 相似文献
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不对称数字用户线(ADSL) 总被引:11,自引:3,他引:8
本文对不对称数字用户线(ADSL)的基本概念,所能提供的宽带业务、技术性能、系统组成作了和说明,并指出利用ADSL,把宽带信息沿普通电话线(铜线)送到千家万户,是数十年时间内过渡到光纤到家(FTTH)的有效传输手段。 相似文献
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ADSL: a new twisted-pair access to the information highway 总被引:3,自引:0,他引:3
The asymmetric digital subscriber line (ADSL) takes advantage of the existing twisted-pair copper loop that currently provides customer access to the telephone network. An ADSL modem is placed at each end of the loop to create a high speed access link above the existing telephone service. Since ADSL makes use of the existing copper telephone line, its application in the telephone network can conceivably be nearly as ubiquitous as the public telephone network itself. With ADSL, it is possible to connect small numbers of customers to broadband services in areas where full upgrade to hybrid fiber coaxial or fiber facilities is not economical in the near term. ADSL systems offer a means to introduce broadband services using the embedded base of metallic loops in areas where optic fiber-based, hybrid fiber-coaxial radio systems or other broadband transport systems may not be scheduled for deployment in time to meet business needs and customer demand. The article concentrates on ADSL systems capable of at least a nominal 6 Mb/s payload transport toward the customer, in addition to associated upstream channels and symmetrical “telephony” services via nonloaded loops that comply with carrier serving area design guidelines 相似文献
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The shortcomings of the existing asymmetric digital subscriber line (ADSL) standard ANSI T1.413 for application with the integrated services digital network (ISDN) are explained. An ADSL system modified by increasing the high-pass cutoff frequency of the splitter to about 140 kHz and, therefore, moving also the pilots, has been simulated under noise conditions and the ISDN requirements of the German subscriber line network. The reach reduction due to ISDN compared with the “plain old telephone service” (POTS) application is shown to he between 10% and 15%. It is proposed to apply ISDN ADSL rather than POTS ADSL 相似文献
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ADSL技术是一种调制技术,在双绞铜线的两端分别接入ADSL调制解调器,即可利用其高频宽带特性高速传送数据.本文全面阐述了实现用户线路高速化的ADSL的技术以及应用. 相似文献
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ADSL技术发展及其应用 总被引:1,自引:0,他引:1
ADSL(Asymmetrical Diital Subscriber Loop,非对称数字用户环路)技术是一种调制技术,在双绞铜线的两端分别接入ADSL调制解调器,即可利用其高频宽带特性高速传送数据。本文全面阐述了实现用户线路高速化的ADSL技术基础及其应用。 相似文献