一种用于CATV/ISDN/VOD的新型光纤到户无源光网络

讨论了一种用于CATV／ISDN／NOD的新型光纤到户无源光网络(PON)，该网络使用了高能激光器、远程泵浦的掺饵光纤放大器(EDFA)、经济的下行接收机和上行半导体激光器，在CATV本地环路中可大幅度地减少设备费用。该网络采用了避免受激布里渊散射(SBS)技术和EDFA远程泵浦技术，从而提高了系统的可靠性和稳定性。     

Optical fiber cable and wiring techniques for fiber to the home (FTTH)

NTT group’s new medium-term management strategy calls for 20 million optical subscribers by 2010, and NTT Laboratories is pushing forward to meet this goal. Before that date, an efficient optical access network must be constructed, and afterwards, when the era of mass optical communications finally arrives, the facilities and equipment supporting the network will have to be effectively operated and maintained.At NTT Access Network Service Systems Laboratories, we are developing various technologies to correspond to the massive deployment of optical broadband services. We are also developing various new technologies for efficiently operating optical access network systems that will continue to expand in the future, and to supply our customers with good services.This paper provides an overview of the new optical access network system technologies that are being developed at NTT Access Network Service Systems Laboratories to address these issues.     

基于EPON+MoCA的CATV高速接入网方案设计

阐述了MoCA技术标准c.LINK的技术特点与优势.针对传统广电双向改造方案所提供的10带宽难以满足用户高清电视、高速下载需求问题,以MoCA技术多频道高速带宽优势为基点设计了基于E-PON+MoCA技术的有线电视高速宽带接入网方案.     

Design issues relating to the provision of integrated services on abroadband coaxial cable local area network

A tutorial overview is given of modern designs that have been researched and developed by the authors to satisfy a range of application requirements. The requirements of such networks are first reviewed, and the characteristics of a typical broadband cable system with respect to frequency allocation strategies and signal amplitude levels are described. Three modems that have been implemented to meet a range of services are then presented     

基于电力光纤到户的网络切片资源管理方案

为解决电力光纤到户项目中网络管控不灵活、业务种类繁多且QoS复杂等问题,提出了基于电力光纤到户的网络切片资源管理方案和基于网络切片感知的多业务融合动态资源分配算法。仿真结果表明,所提方案能够有效实现不同切片的QoS保障,并显著提升网络资源利用率。     

Loop-network configuration and single-mode optical fiber cable technologies for subscriber network

This paper will discuss optical fiber cable distribution networks for accomodating the immediate introduction of optical subscriber networks. The concepts of cable distribution system design, the maintenance systems and the cables and jointing technology for supporting these systems will be discussed. The results of experiments using related technology will also be discussed.     

城市光纤CATV网络拓扑结构探讨

简要介绍光纤同轴电缆混合网（ＨＦＣ）的优势,分析ＨＦＣ网的几种拓扑结构及优缺点,并对城市ＨＦＣ网拓扑结构的工程实际进行了探讨。     

一种解决光纤CATV网回传通道增益驱动控制的新途径

概述传统光纤ＣＡＴＶ网回传技术,指出其缺陷,提出一种解决ＣＡＴＶ回传通道增益驱动控制的新方案,给出了具体设计电路和控制程序,并对该新方案的性价比进行了分析。     

IP/TV VOD网络视讯系统解决方案

分析了IP／TV VoD网络视讯系统的技术(系统结构、工作原理等)、产品特点、功能特点，给出了设计方案及其设备配置选型，结合实际的工程建设对网络进行了运行分析。     

A comparison of UPS for powering hybrid fiber/coaxial networks

Four distinct uninterruptible power supply topologies are presented here for powering hybrid fiber/coaxial (HFC) networks. Topologies based on a low frequency isolation transformer are found to have better efficiency than the topologies with high frequency transformer. However, the latter topologies have much better performance in terms of transient response, quality of the output voltage, input power factor, total harmonic distortion of the input current, size and weight. The series-parallel resonant based UPS topology is found to have best overall performance for the emerging HFC applications     

End-correction network of a coaxial probe for microstrip patchantennas

A simple end-correction network for the constant current probe model of probe-fed microstrip patch antennas is derived. The parameters of the network are solved asymptotically and verified by the numerical solution of the integral equation formulation. Based on the analysis of a problem concerning a coaxial-fed microstrip patch, it is concluded that: (1) TEM (transverse electromagnetic) aperture field approximation can provide an accurate result to the input admittance, and there is no need to introduce a specific correction network for most applications; and (2) Constant current probe is valid only when both k₁ h≪1 and a/h≪1 are satisfied. An end-correction network consists of a series inductance and a shunt capacitance should be used in other ranges or for higher accuracy     

带漏泄段同轴电缆激励的2GHz无线电波在大型封闭区域内的传播

本文给出了在大型封闭区域,用带漏泄段的同轴电缆作为发射天线时,2GHz窄带和宽带无线电波传播特性的测量结果,对于窄带信号、主要测量了传播过程中的衰减,测量结果表明,在平行于电缆方向上,接收信号的电平比垂直于电缆方向的电平大;接收信号的快衰落服从瑞利分而,而慢衰落不服从正态分布。对于宽带信号,测量了多径脉冲响应,得到了均方根时延扩展及其概率分布。     

Theory on small radiating apertures in the outer sheath of a coaxial cable

An analytical expression for the aperture field is obtained from an integral equation formulation and a subsequent use of a quasistatic approach in which the dominant part of the solution can be extracted from canonical problems. Unlike the conventional approach of replacing the aperture field by equivalent dipoles, our method retains the basic features of the propagating mode in the coaxial region, and the radiation characteristic of the coaxial cylinder. An equivalent network representation of a small aperture is then derived. The network equivalence of a symmetrical aperture with its axes oriented in the direction of the incident field is shown to consist of a lumped shunt capacitanceC_{b}and a series impedanceZcomposed of an inductive elementL_{b}, a capacitive elementC_{T}and the input admittanceY_{binfty}of the external antenna, all in parallel.     

一种光缆故障定位方法研究

随着移动传输网络的日趋庞大,维护网络安全尤其重要,本文从具体维护技术角度,提出了一种实用的光缆故障定位方法,解决了资源模型和纤芯监测数据互通技术中衔接的问题,有效提高了故障处理效率.     

Research on Advanced Switching Techniques for the Evolution to ISDN and Broadband ISDN

Switching techniques for packetized data and for video communications are a key element in the evolution of the central office from IDN, to ISDN, and to broadband ISDN. An evolutionary scenario, based both on a short-term and on a longterm reference architecture for the switching system, is proposed, and two advanced switching techniques for labeled switching and for diffusive video switching, respectively, are analyzed which match the above scenario well. Plans and preliminary results are also reported on experimental research through laboratory demonstrators of the two switching techniques.     

Traffic studies of a multiplexer in an ATM network and applications to the future broadband ISDN

In the first part of this paper the influence of the arrival process on these three performance parameters is discussed. The values of these three performance parameters depend strongly on the utilization distribution over the input trunks of the multiplexer while the total utilization on the input trunks is fixed. If there is the same utilization on all input trunks, the values of these three performance paramters reach a maximum. This result is also valid for an ATM switching matrix with a separate FIFO buffer at each output trunk. In the second part of this paper some examples are provided of how to apply the results of these studies to the future broadband ISDN which is intended to transmit services with very high bit rates (e.g. 135 Mb/s) as well as services with very low bit rates (e.g. 64 kb/s).     

A view of fiber to the home economics

Fiber to the home in the U.S. market has not been deployed as rapidly as many had hoped or predicted. We examine some of the historical, competitive, and economic reasons for this. We argue that, from a competitive service perspective, it may be difficult to construct compelling business cases for large-scale deployment without either a technical need for fiber, or significant changes in either public policy or industrial organization.     

On the electromagnetic field of a dielectric coated coaxial cable with an interrupted shield

A boundary value treatment is used to derive field expressions for a dielectric coated coaxial cable with a gap in the shield. Specific results are given for an incident TEM mode in the interior coaxial region. For example, it is shown that, for the VHF region, as much as 18 percent of the incident power is radiated into the external region via a single circumferential gap in the shield. Comparable amounts of power are transferred to a reflected TEM mode in the cable and into surface waves in the dielectric jacket.     

有线电视城网规划应注意的几个问题

随着有线电视事业的发展和网上新业务的增加 ,早期建设的以同轴电缆为主干线的城市有线电视网的更新改造成为有线电视的建设重点。建设一个宽带双向多功能综合信息传输网 ,要综合考虑诸多因素 ,城市有线电视分配网络规划除常规的Ａ ,Ｂ平台、链路损耗、“光发”、“光收”等参数设计外 ,还应注意以下问题。1　多设分前端组成环状 +星状的拓扑结构网络用户的增加和综合业务的发展 ,都要求城市应构建一个完整的具有自愈功能的有线电视环状网络 ,以提高网络的可靠性和系统性。在环网上可多设几个分前端 ,分前端与有线电视中心构成环状 (可多环 …     

New experiments on the behaviour of the hybrid TEM-dual surface wave in a coaxial cable

A new series of experiments, using a standing-wave method of measurement as well as a repetition of the previous resonant-cavity work, endorses the conclusion that a significant reduction of attenuation is possible, when the inner conductor of a coaxial cable is coated with a dielectric of higher permittivity than that of the surrounding medium, between the two conductors.