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宽带接入网络是近年来各运营商投资建设的重点,主要接入手段有以太网接入、ADSL和VDSL等技术,各运营商根据其网络特点进行了大量的实验。这几种宽带接入技术有什么区别,哪种更适合我国的国情,其应用前景如何,这些正是电信运营商和制造商目前最关心的问题。最近传统铜线上的VDSL接入方式因其接入速率大幅度提高而备受业界关注,通过对VDSL技术原理和实现方式的分析,我们认为,VDSL(EVDSL-基于以太网的VDSL)是远程以太网技术,而不是ADSL的升级版本。VDSL(Very high speed DigitalSubscriber Line)90年代中期开始… 相似文献
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GordonJ.Reesor 《今日电子》2002,(7):33-35
到底哪种线路编码技术-DMT(离散多音)还是CAP(无载波幅度和相位调制)/QAM(正交幅度调制)更适合于VDSL(甚高速率数字用户线路)呢?有关这一问题的争论已存在多年了。有些人认为虽然国际标准团体在ADSL(非对称DSL)技术中选择了DMT,但对VDSL而言,CAP/QAM更为合适。 确实,VDSL和ADSL面临不同的线路编码问题。然而,对实际线路状况和其他实际问题的工程分析却表明,DMT适用于VDSL的理由比在ADSL中还要充足。 相似文献
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首先回顾了VDSL(甚高速数字用户环路)技术的发展,接着介绍了第二代VDSL的特点及其新技术,最后对其应用进行了探讨。 相似文献
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随着上海贝尔宣布获得广东电信首个高速数字用户环路2(VDSL2)网络的部署合同,对铜线双绞线的最后500米宽带接入的潜力挖掘进入到新阶段。据了解,这一项目也是国内首个投入规模运营的VDSL2项目。 相似文献
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介绍了基于VDSL的以太网接入技术(EoVDSL)。它结合了VDSL技术和以太网技术的优点,还可以与EPON技术相结合,作为一种经济高效的宽带接入方案。 相似文献
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J W Cook 《BT Technology Journal》2001,19(2):173-175
The design of a service splitter filter for VDSL has been studied for the case of VDSL deployed at a remote node such as a flexibility cabinet and where it is desired to apply VDSL signals over either telephony or ISDN signals originating in the telephone exchange. Even taking into account all of the requirements of telephony, ISDN, VDSL, HPNA and RFI, it is shown that a remarkably small and simple splitter will suffice. 相似文献
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VDSL是数字用户线技术中的最新技术,宽带接入的最佳方案之一。为了提高VDSL系统的传输速率,它有必要兼容现行ADSL系统的频谱。本文通过对VDSL系统的双工方式及兼容ADSL系统的可行性分析,提出了VDSL系统的可用功率谱密度及TDD-VDSL系统兼容ADSL频带的子频带抑制方法,并进行了仿真分析。结果表明在不同的运行环境下,都有很好的性能,是一种有效的实用方案。1 相似文献
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本文首先介绍了VDSL的体系结构,然后就实现VDSL接入的关键技术如线路编码技术,以及复用技术和回波抵消技术等相关技术进行了分析,最后指出了VDSL的发展现状和前景。 相似文献
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《Communications Magazine, IEEE》2002,40(12):92-105
This article presents the prototype developed to prove the Zipper concept and contribute to VDSL standardization. This solution includes the hardware and software needed to demonstrate that the VDSL multicarrier is a feasible, flexible, high-performance, competitive solution. The prototype provides the network management and telemetry software needed to simplify system setup and performance evaluation, respectively. It includes two interfaces: one to plug a twisted pair cable or a cable simulator, and the other to connect the ATM transport protocol. A 155 Mb/s (OC-3 rate) ATM-SDH/SONET interface is provided too. The first measurements performed between two VDSL modems, with injected noise of 20 VDSL equivalent lines, show that it is possible to transmit (in downstream and upstream directions) payload bit rates up to 48 Mb/s at 300 m and up to 25 Mb/s at 1500 m using 0.5 mm copper cables. The prototype has been designed using a modular and flexible architecture able to allow future VDSL modem extensions. The reuse of this prototype is expected for other applications where OFDM technology applies. 相似文献
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ATM passive optical networks and integrated VDSL 总被引:1,自引:0,他引:1
《Communications Magazine, IEEE》2000,38(3):174-179
VDSL offers a cost effective solution for the provision of a full-service broadband access network. Standards are emerging that will define the line code, duplexing method, and spectrum requirements for VDSL. VDSL chipsets and modules are becoming available that allow the technology to be evaluated in the field. This article describes the architecture and hardware integration that has been performed in integrating VDSL technology into an ATM PON system 相似文献
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甚高速数字用户线(VDSL)是数字用户线(DSL)家族中速率最高的接入方式.新一代VDSL速率最高可到100Mbit/s以上,包括对称传输和非对称传输以及多种不同的传输速率.由于VDSL的传输速率高,其对应的传输距离和其他DSL技术相比较短.调制方式是VDSL中的核心技术,目前有两种并存的方式,离散多音(DMT)与正交/调幅和无载波调幅/调相(QAM/CAP).文章主要介绍这两种调制方式,并从多个方面对其优、缺点进行比较. 相似文献
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Cendrillon R. Ginis G. Van den Bogaert E. Moonen M. 《Communications, IEEE Transactions on》2007,55(5):860-863
This letter presents a linear crosstalk precoder for very-high-speed digital subscriber lines (VDSL) that has a low run-time complexity. A lower bound on the data rate of the precoder is developed, and guarantees that the precoder achieves near-optimal performance in 99% of VDSL channels 相似文献
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首先说明甚高速数字用户线(VDSL)的由来,其次说明铜线用户线性能的影响,然后解释VDSL的业务分类和VDSL的参考模型。 相似文献