高功率光纤激光器相干合成技术

介绍了目前国内外光纤激光器相干合成技术的最新进展,系统总结和分析了典型的相干合成方法,分析了其优缺点,最后对光纤激光器相干合成技术的发展作了展望.     

分析通信系统光纤技术应用及其发展

光纤技术推动了我国通信系统的发展,将全球联系成为一个整体,加快了与世界的交流和沟通。本文着重介绍了光纤通信技术的特点,随后又对光纤技术在我国通信系统中的应用进行了阐述,最后对光纤通信系统中出现的新的发展方向---光网络进行了细致地分析。     

分析通信系统光纤技术应用及其发展

光纤技术推动了我国通信系统的发展,将全球联系成为一个整体,加快了与世界的交流和沟通。本文着重介绍了光纤通信技术的特点,随后又对光纤技术在我国通信系统中的应用进行了阐述,最后对光纤通信系统中出现的新的发展方向——光网络进行了细致地分析。     

浅析光纤通信技术发展的现状与前景

随着光子技术和电通信技术的发展与完善,光纤通信技术应运而生,并逐步成为我国最主要的信息传送手段,光纤通信技术的信息容量占到了90%。我国光纤技术自研究至今已有30多年的历史,在这30多年的发展中,我国光纤技术取得了长足进步。文章分析了光纤技术的发展现状,对未来光纤技术的发展作了展望。     

书讯

《电视新技术》译文集征订通知为了引进国外电视新技术,以促进我国电视的发展,由机械电子工业部第三研究所组织翻译的《电视新技术译文集》即将出版。该译文集收译了英、德、日文种目前国外电视最新技术资料。主要内容包括:如何提高彩电的图像质量;如何采用电视光纤传输系     

CATV的光纤传输和分配综合网络

本文对ＣＡＴＶ的光纤传输和分配综合网络作了概述。在简介了缆传电视的光纤传输系统及其所用的光发射机和接收机之后，对光链路及其级联特性作了较详细叙述，并对网络体系结构和网络设计作了实用性介绍。     

三网融合及光纤入户技术浅析

在我国经济快速增长的今天,我国网络技术和电子信息技术得到了快速发展,信息化技术的发展极大的改善了人民的生产生活活动。宽带、电视、视频等传送信息化方式正在逐渐的趋于统一,他们之间的业务范围也在慢慢的重叠,所以,逐步电信、电视和互联网的有机融合,实现三网合一是我国当前信息化技术发展的趋势,这样就可以为人们提高更加多样化和便捷化的服务。而我国光纤技术的快速发展,就为三网融合打下了坚实的技术支持。本文主要对三网融合和光纤入户技术进行探讨和分析。     

构建在光纤有线电视网上的会议电视系统——模拟会议电视系统VCON的实践

本详尽地介绍了一种新颖的构建在光纤有线电视网上的会议电视系统VCON,下行信号借助于光纤CATV网的广播下行通道,上行信号则采用了成熟的PFM（脉冲频率调制）技术传输。与其它的会议电视系统相比较,具有广播级的图像质量、远距离的传输（可达100km)、完善的功能（具有双向通信功能、摄像机遥控功能、计算机控制和切换功能）、简单的系统结构、低廉的成本（只有数字会议电视系统的十分之一）等显特点。同时VCON电视会议系统还能用于电视新闻节目的回传和电视实况的转播,系统的使用效率很高,特别适合于我国广播电视事业发展的要求。因而在许多光纤CATV网中得到了广泛地应用。     

光纤族系列绪论

目前,在有线电视和通信网络中,采用光纤干线已成主流。随着光纤的技术进步,光纤族也已形成系列。本文拟对正在不断开发和应用的光纤族系列产品作一简介。 1 光纤的分类 光纤是光导纤维(OF:Optical Fiber)的简称。但光通信系统中常常将Optical Fiber(光纤)又简化     

残留边带调幅光缆电视光纤传输系统中的频道容量

与传统的电缆电视系统相比，残留边带调幅光缆电视光纤传输系统具有很大的优越性，因而对该系统的研究具有重要的产用意义。文中对ＭＡ－ＶＳＢＣＡＴＶ光纤传输系统的频道容量及其相关因素作了探讨，并导出了一些相关的计算公式。     

Testing HDTV terrestrial broadcasting systems

The Advanced Television Test Center (ATTC) is a private sector, nonprofit organization created to undertake full, fair, and impartial testing of the various advanced television (ATV) systems that have been proposed as the United States terrestrial broadcast standard. Cable Television Laboratories (CableLabs) organized by the cable television industry operates, in cooperation with ATTC, a state-of-the-art laboratory testing facility capable of thoroughly evaluating the proposed ATV systems when transmitted by cable TV, including both coaxial cable and fiber-optic transmission. Presently there are six systems scheduled for test by the ATTC and CableLabs. The systems and their scheduled test dates are shown. One of the systems is an enhanced NTSC compatible system and the other five are high-definition television (HDTV) simulcast systems. Four of the simulcast systems are digital. Both objective and subjective tests of all six systems are discussed     

A scenario for the deployment of interactive multimedia cabletelevision systems in the United States in the 1990s

This paper discusses the key technologies that are enabling the transition from analog to digital interactive television. Also discussed is a proposed three-phase scenario for the U.S. deployment of interactive multimedia cable television systems during the remainder of the decade of the 1990s and some of the social implications of such networks     

The design of large-scale networks

The application of computer techniques to difficult large-scale network problems is discussed. The physical characteristics of two types of systems are described--computer-communication networks and cable television distribution systems. Two fundamental algorithms are presented, and applications to routing, reliability, and design of computer networks are given. The detailed engineering decisions that can be made by computer in the design of practical large-scale networks are illustrated by example for cable television systems. These examples are chosen to indicate the richness and difficulty of the problem of applying computers to network design.     

A backbone highway communications system using coaxial cable

The problem of providing the communication link for modern highway management and control is analyzed. A 100- mile span of highway is analyzed for typical voice and control function requirements plus closed circuit television monitoring capability. Based on this analysis, the number of channels and hence the bandwidth required to meet typical requirements is developed. It is proposed that a coaxial cable system can best provide the bandwidth and access flexibility that will be necessary for the many links required for effective highway management. A coaxial cable system as a transmission path is shown to be two dimensional in that it involves absolute signal levels as well as spectrum considerations. An analysis of distortion characteristics of state of the art coaxial cable systems is included to arrive at signal to noise plus distortion ratios versus cable length and amplifier gains. Typical cable costs, burial and tunneling labor costs are discussed to show economic practicality. Finally, two high-capacity cable systems are discussed to illustrate the communications capacity of coaxial cable systems.     

Cable television on fibre in stand-alone networks and in systems combined with telephony

This paper presents details of dedicated cable television systems (stand-alone cable TV), and combined cable TV/telephony systems, based upon the economic implementation of optical fibre technology. The factors that determine the choice of these two approaches are described and examples are given based upon systems designed by Raynet Corporation. Techno-economic issues are debated and the need for effective future-proofing is emphasized. In particular, the critical choice between fibre to the last amplifier (FTTLA) and fibre to the curb (FTTC) is discussed. Architectures are described for trunk and distributed systems and performance characteristics are given for a specific network, optical elements and electro-optic interfaces. Detailed considerations relating to future developments conclude the paper.     

Broadband: the last mile

The regulatory and service drivers that are prerequisites for local access evolution to the broadband integrated services digital networks are discussed. A tutorial on the state of the art in relevant technologies is presented, and it is shown that many of the technologies are not yet mature. The broadband technologies discussed are analog cable television systems, optical fiber, optical amplifiers, optical receivers, transceivers, and image compression systems. Regulatory considerations include bandwidth on demand and competition     

A review of cable television: The urban distribution of broad-band visual signals

This paper presents a review of the distribution of broad-band visual signals in urban areas on cable television systems. Following a brief introduction, the early history of cable distribution in the U.S., U.K., and Canada is described. The architecture of wide-band visual distribution networks is presented, based on developments in Canadian cable systems which have formed the model for North American development. The present status of fiber optics in cable systems in reviewed. The paper concludes with a summary of probable development directions. The paper includes an extensive bibliography covering cable television.     

Interactive Cable: Federal Policy and Programs

Urban development of cable, generally regarded as a prospective testbed of interactive cable services, has not started on the optimistic path many predicted when the current FCC cable regulations took effect in 1972. Cable growth, and industry emphasis, have been markedly within franchises rather than in new franchises recently. Economic rather than regulatory forces may have been largely responsible for this effect. This paper describes the factors in Federal regulatory policy that impinge on interactive cable systems and new service developments, including pay television, the first significant new service to emerge. Recommendations of the Cabinet Committee on Cable that are potentially significant for the development of new cable services, enhancement of rural broad-band services, and development of modern interactive systems are discussed. A few current programs compatible with the Committee's recommendations for Federal support in cable public service development are also indicated.     

有线电视网络模数混传系统各关键点电平设置

通过对有线电视网络模、数混传系统各关键点电平设置的讨论,为有线电视网络模数混传时期系统的调试和维护提供参考数据。     

有线电视前端设备运行监测软件的设计

设计一个统一的运行监测平台,利用微机对常年不间断工作的不同厂家、不同型号的有线电视前端设备运行数据进行实时采集和检测,对保证有线电视信号传输的稳定、可靠和安全播出有着十分重要的意义.主要讨论有线电视前端设备运行监测系统微机软件的设计.