县级有线数字电视多通道字幕插播方案

通过对基于1 550 nm长距离模拟光纤传输系统下县级有线数字电视多路字幕插播的实践,解决了县级有线网络在加扰射频数字流情况下的多路字幕插播等问题,该方案在县级有线数字电视系统中具有广泛的应用前景。     

Optical Fiber Submarine Cable System Development at KDD

An optical fiber submarine cable system using longwavelength and single-mode optical fiber is expected to provide economical long-haul digital transmission. This paper describes the recent research and development on an optical fiber submarine cable system for international communication at the KDD Research and Development Laboratories. An experimental model including cable and repeaters has been designed and manufactured. An experimental repeater of 1.3 μm and 280 Mbits/s was laid at a depth of 1500 m and its fundamental performance was measured in November 1981. Test production of longlength cable having a single continuous length of 30 km became possible in the end of 1981. In early June 1982, the experimental system with a 50 km cable length and two repeaters operating at 300 Mbits/s and 1.3 μm wavelength was laid in a loop into the Sagami Bay from the KDD Ninomiya Submarine Cable Landing Station.     

Optical Fiber System Applications Aspects in Future NTT Networks

This paper describes some aspects of optical fiber cable system applications in future NTT transmission networks, considering voice transmission as predominant even in future transmission networks in accordance with demand forecasts. The desirable optical fiber cable transmission system which should be developed and introduced is discussed taking into account optical fiber costs, demand estimates, pertinent technological developments, etc. It was concluded that the following process of introducing optical fiber cable transmission systems should be feasible. In the first step, approximately 32 Mbit/s and 100 Mbit/s digital transmission systems should be employed for short and medium haul trunks with heavy traffic using graded index optical fibers. A large capacity, long haul digital transmission system, such as a 400 Mbit/s system using graded index or, if possible, single mode optical fiber should be introduced next. The optical fiber cable costs at which fiber systems become economical, depend upon the application area. For short and medium haul systems, 40¢ per meter per core is required, but $2 per meter per core is sufficient for large capacity, long haul systems. For a short haul system operating at approximately 1.5 Mbits/s or 6 Mbits/s, the advantages of its introduction greatly depend on optical fiber costs which should be less than 20¢per meter per core.     

Undersea fiber cable technology

Compared with the conventional coaxial undersea cable systems, an optical fiber undersea cable system has a great technical and economical advantage. It is also suitable for digital transmission. In this paper, the optical fiber undersea cable technology (including optical fiber cables and repeaters), which is now in the research and development stage in several countries, is reviewed.     

Army Fiber Optic Program: An Update

Modernization of Army tactical communication systems has placed emphasis on meeting new digital data handling requirements. An all digital transmission facility will require new radio systems and substantially improved cable systems which can overcome present length-bandwidth limitations. These new digital systems must have, in addition, superior reliability, freedom from electromagnetic countermeasures, and be highly mobile. These requirements are driving the development of new distributed multiplexed radio systems and an intensive investigation into the utilization of fiber optic cable systems. Fiber optic cables have the required capabilities of: EMI, RFI, and crosstalk immunity, substantially reduced deployment weight and volume, and freedom from electromagnetic pulse effects. Recent developments in fiber technology have significantly reduced the risk associated with the use of fiber cable in a tactical field Army installation. However, there are some problems that need to be resolved before fiber optic systems can be fielded. This paper will discuss Army application areas, components and system development efforts directed toward fielding tactical fiber optic systems.     

区级有线数字电视网络改造中1550系统的应用

主要分析了1 550系统在区级有线数字电视发展中应用的优势,在原有线电视1 310 nm波长光纤联网的基础上,以1 550 nm波长的光纤系统传输广播电视信号到镇乡和城区节点,以提高传输质量。介绍了掺铒光纤放大器（EDFA）在1 550 nm波长的光纤传输中的应用,论述了改造设计时应注意的问题。     

雷达信号光纤传输系统

提出了一种可替代传统电缆的光纤传输系统,并介绍了光纤传输系统中数字部分与模拟部分的工作原理、设计方法以及部分关键技术.     

有线电视传输系统常见故障维修

随着技术的不断发展,有线电视网络已从同轴电缆向光纤、模拟信号向数字信号、单向传输向双向传输转变,甚至向全光信号的方向发展。但因技术尚未完全成熟,其仍旧存在传输系统故障问题,相关人员应提高对其的重视程度。文中深入分析了有线电视双向网络传输的特点,对有线电视传输系统常见故障及维修方法进行了探究,并对屏幕横条、断线、终端无法注册、互动点播进入慢和同一局端下网速不稳定等故障进行了研究,以期为技术应用和有线电视传输系统的安全工作提供借鉴。     

基于ARM7平台的多媒体监控系统研究

随着数字视频压缩技术的不断发展,基于数字技术的多媒体监控系统开始逐步替代传统的图像监控系统。基于多媒体监控系统采用数字技术对信号进行采样和压缩,所以它可以实现网络传输,而不用采用传统的视频电缆或者光纤传输,大大节省了成本,同时更容易实现对图像的存储、处理和控制。论文采用嵌入式操作系统,在ARM7平台上实现多媒体的监控。     

超长光电复合海缆光缆单元的研发与制造

本文介绍了超长光电复合海缆光缆单元的研发和制造,该光缆单元是35KV光电复合海底电缆中的通信单元,由于海底电缆接续技术复杂,不允许有接头,要求单盘光缆长度超过36公里,本文论述上述光缆的基本结构、设计思路、工艺控制、试验结果等。     

The FLAG cable system

The Fiberoptic Link Around the Globe (FLAG) cable system is a 10 Gb/s synchronous digital hierarchy (SDH) based undersea fiber optic network. When fully operational, FLAG will connect 12 countries with over 120000 voice channels via 27000 km of mostly undersea cable. FLAG will incorporate a new generation of undersea fiber optic system that uses erbium-doped fiber amplifiers and will be jointly supplied by AT&T Submarine Systems Incorporated (SSI) and KDD-Submarine Cable Systems (SCS) Inc. When completed, FLAG will meet or exceed all relevant international performance standards, have greater reliability and availability than previous systems in the region, and conform to all ISO 9000 quality standards with respect to design, development, production, installation, and service     

The emergence of integrated broadband cable networks

The basic attribute of capacity, now extended by a series of technical innovations, has transformed the crude cable platform into a powerful network capable of supplying advanced broadband telecommunications services to consumers. The author provides an outline of the technical migration that has taken place in cable over the past 10 years. This evolution can be summarized in three steps: fiber, digital, and packets. The first major architectural step occurred in the late 1980s. Single-mode fiber provided a way to replace the string of trunk amplifiers that were the cause of quality and reliability problems in cable. If the composite signal carrying 30-100 TV channels could be delivered into the coaxial network near the home, the trunk amplifiers could be eliminated. The development of analog lasers that could be AM modulated with very broadband signals (and perform at useful signal to noise margins) enabled the addition of fiber to the cable infrastructure. The cable network migrated to the hybrid fiber coax (HFC) structure that uses fiber to deliver signals to neighborhood nodes. From the nodes, the signals are redistributed to homes using the tree and branch coaxial plant previously in place     

Optical Fiber Facilities for Subscriber Loops

This paper gives an overview of the introduction and subsequent development of optical fiber cable and its application to subscriber networks enabling economical broad-band services, such as video and high-speed digital data transmissions. This paper also outlines NTT's developments on subscriber optical fiber cable technology-in particular, the five-fiber ribbon cable structure, mass-fusion splicing machine, and multifiber connector-in its ongoing endeavors to establish economical and flexible subscriber optical fiber networks which provide optical fibers to each subscriber.     

基于LVDS的长线传输模块设计

针对并行长线数据传输速度过慢的实际情况,文中介绍了一种基于LVDS串行总线长线传输模块设计。系统采用FPGA作为主控芯片,采用高速串行数字接口自适应电缆均衡器和电缆驱动芯片,增强长线电缆驱动能力,提高了LVDS数据传送的距离。其中通过双绞线电缆、光纤,DS92LV1023和DS92LV1224型号的LVDS芯片与驱动芯片CLC001和CLC006相互配合能使数据传输100米。该系统已投入使用,其性能具有较高可靠性、很强的应用价值。     

Design and performance of a novel automatic fiber line testingsystem with OTDR for optical subscriber loops

This paper proposes architecture for a novel automatic fiber line testing system with an optical time-domain reflectometer (OTDR) and describes the system requirements, the design method, and the system evaluation. The results of a trial on a manufactured system and an evaluation of its characteristics are presented with evidence that an in-service optical fiber can be tested with no degradation in communication quality and the desired measurement accuracy and system component characteristics can be realized. In addition, it is confirmed that a failure between an optical fiber cable and a digital service unit (DSU) can be identified with 100% accuracy     

大容量中心束管式光纤带光缆的设计与制造

随着通信行业向着数字化、宽带化、智能化方向的发展,光纤网络的建设将由骨干网转向局域网与城域网,由于连接的节点较多,往往需要铺设大芯数的光纤光缆。中心束管式光纤带光缆因其集成度高、占用路由资源少、成本低等特点,将会得到广泛应用。本文就大容量中心束管式光纤带光缆的设计与制造进行探讨。     

Fiber-Optic Hybrid Digital Transmission System Experiment

The hybrid digital transmission system, involving 2Rrepeaters between 3R (Reshaping, Retiming and Regenerating)-repeaters, is a suitable system for fiber-optic transmission. The 2R (Reshaping and Regenerating)-repeatered line enables bit rate free transmission, but cannot suppress the accumulated timing jitter in transmitting pulse streams. The trial 1-8 Mbit/s transmission system, using step-index multimode fibers and light emitting diodes, was designed and tested. Multirepeater transmission experiments using optical fiber cable laid in an underground cable tunnel were also performed. The timing jitter accumulations were measured through the multi-repeatered line. Measured timing jitter values were in good agreement with theoretical values. Experimental results show satisfactory feasibility of a fiberoptic hybrid digital transmission system using step-index or gradedindex multimode fibers.     

基于双向HFC的数据通信系统及其接入终端的设计

双向光纤同轴电缆混合网（ＨＦＣ）是今后宽带多媒体通信的重要基础网络之一。本文对基于ＨＦＣ的宽带数据通信系统提出一种集成的解决方案，并具体描述该系统接入终端即Ｃａｂｌｅ Ｍｏｄｅｍ的各功能模块原理及其软硬件设计的实现方案。     

基于DSP的高精度数据采集与处理系统

结合海底光缆无源探测技术设计了一种由TMS320VC5402型DSP和AD7714型A/D转换器组成的高精度数据采集系统,并由TMS320VC5402实现高性能IIR数字滤波器.     

20．5km，139．264Mb／s数字彩色电视光纤传输系统

1985年3月20日，在桂林光通信研究所召开的四状群数字光端机和数字彩色电视光纤传输系统鉴定会上，我们采用国产光电器件和多模渐变型宽带光纤，成功地实现了139.264Mb/s数字彩电的20．5km无中继传输：系统性能达到了我国GB1582-79规定的短程线中轴彩电传输标准的指标。