2022年通信专业英语实用 .pdf

第页共页英文：Introduction to Optical Fiber CommunicationOne of the most important technological developments during the 1980s has been the emergence of optical fiber communication as a major international industry. One indication of the extent of this development is the total length of installed fiber, which was estimated to be 3.2 million kilometers in the U.S. alone by the end of 1987. Over 90% of this fiber was placed in service during the time period of 1982-1987. Long-haul trunk installations have been dominated, accounting for about 95% of the fiber in the U.S. Although telecommunication is the rationale for most of the current interest in fiber optics, this was not the case during the early days of the technology. The researchers who produced the first clad glass optical fibers in the early 1950s were not thinking of using them for communications; they wanted to make imaging bundles for endoscopy. Fiber optics was already a well-established commercial technology when the famous paper by Kao and Hockham, suggesting the use of low-loss optical fibers for communication, appeared in 1966. The first low-loss(20 db/km) silica fiber was described in a publication which appeared in October of 1970. The date of this publication is sometimes cited as the beginning of the era of fiber communication. Although this development did receive considerable attentiong in the research community at the time, it was far from inevitable that a major industry would evolve. 中文：光纤通信简介在 20世纪 80年代最重要的技术发展已作为一个主要国际光纤通信的出现行业。这方面的发展程度的表现之一是安装的光纤，估计由 1987 年底的 3.2 万公里， 仅在美国的总长度。这种纤维超过90被安置在服务期间的1982-1987年的一段时间。 长途干线装置一直占主导地位，在美国占大约95的纤维虽然电信是目前的利率在光纤的理由，这是不是这样，在该技术的初期。第一包层玻璃光纤在20 世纪 50 年代初，研究人员没有考虑使用通信，他们想使内镜成像束。 光纤已经是一个完善的商业技术，花王和 Hockham 著名的论文，建议使用低损耗光纤通信，在 1966 年时出现。第一损耗低 （20 分贝/公里）石英光纤是在1970 年出现在 10 月出版。本刊物的日期有时是引光纤通信时代的开始。虽然这方面的发展确实收到了研究界相当attentiong 的时间，这是不可避免的一大产业发展。浙江万里学院实验报告课程名称：专业英语实验名称：Unit 5 Introduction to Optical Fiber communication专业班级：姓名：学号：实验日期： 2011. 成绩：教师：名师资料总结 - - -精品资料欢迎下载 - - - - - - - - - - - - - - - - - - 名师精心整理 - - - - - - - 第 1 页，共 5 页 - - - - - - - - - 第页共页 20 分贝 /公里的亏损数字仍然太高长途电信系统。纤维是脆弱的，就必须找到一种方法来保护他们。目前还没有合适的光源。研究人员不知道现场端接光缆拼接是否会被实际。最后，还有严重怀疑这些组件是否可以生产足够的经济技术在市场上发挥了重要作用 . 虽然强大的技术壁垒的出现，经济潜力是非常显著的。作为一个结果，研究和开发活动的规模迅速扩大，duing 20 世纪 70 年代初的一些重要问题得到了解决。在中期和后期加速的适销对路的产品作为重点转移， 从研究到工程的进展情况1970s.the 率。纤维损失接近2dB/km 瑞利限制在1.3 m 波长为0.8 微米， 0.3dB/km，1.55m 的 0.15dB/km ，在实验室中产生。微弯损耗的问题，通过使用改进的光纤涂料和布线技术克服。坚固的电缆和多光纤连接器生产现场安装。房间温度在0.8? 0.85m光谱区域经营的商业镓铝砷激光器阈值电流降低到20 至 30 mA范围内，预计寿命在100 万至 1 000 000 小时的范围声称为激光器和发光二极管。的光源和改进光探测器在 1.3m 附近经营， 开发利用低纤维损耗和分散在这个“波长较长的地区”的优势。在此期间进行的几个主要的田间试验，其中包括 ATT 的亚特兰大实验和芝加哥的安装，和日本的用户访问项目。电话公司的一部分，1980 年在组件的性能，成本和可靠性的改进导致重大承诺。光纤很快成为长途中继线的首选传输介质。一些早期的安装使用0.8微米的光源和梯度折射率多模光纤，但到了1983年，城际联系的设计师们在1.3m 方面的思想，1980 年，在组件的性能，成本和可靠性的改进导致众多电话公司受益匪浅。光纤很快成为长途中继线的首选传输介质。一些早期的安装使用0.8 微米的光源和梯度折射率多模光纤，但到了1983 年，城际联系的设计师们在考虑使用1.3m 系统了，The 20 db/km loss figure was still too high for long-haul telecommunication systems. The fibers were fragile,and a way to protect them would have to be found. There were no suitable light sources. Researchers did not know whether field termination and splicing of optical cables would ever be practical. Finally, there were serious doubts as to whether these components could ever be produced economically enough for the technology to play a major role in the marketplace. Although the technological barriers appeared formidable, the economic potential was very significant. As a consequence, research and development activity expanded rapidly, and a number of important issues were resolved duing the early 1970s. During the middle and late 1970s.the rate of progress toward marketable products accelerated as the emphasis shifted from research to engineering. Fibers with losses approaching the Rayleigh limit of 2dB/km at a wavelength of 0.8 m,0.3dB/km at 1.3 m,and 0.15dB/km at 1.55 m,were produced in the laboratory. Microbend loss problems were overcome through the use of improved fiber coatings and cabling techniques. Rugged cables and multifibre connectors were produced for field installation. Room temperature threshold currents for commercial gallium aluminum arsenide lasers operating in the 0.8 to 0.85m spectral region were reduced to the 20 to 30 mA range, and projected lifetimes in the 100 000 to 1 000 000 hour range were claimed for both lasers and LEDs. Light sources and improved photodetectors which operated near 1.3 m were developed to take advantage of the low fibre loss and dispersion in this “ longer wavelength region” . Several major field trials were undertaken during this period, including AT & T s Atlanta experiment and Chicago installation, and Japan s subscriber access project. Improvements in component performance, cost, and reliability by 1980 led to major commitments on the part of telephone companies. Fiber soon became the preferred transmission medium for long-haul trunks. Some early installations used 0.8 m light sources and graded-index multimode fiber, but by 1983, designers of intercity links were thinking in terms of 1.3 m, 名师资料总结 - - -精品资料欢迎下载 - - - - - - - - - - - - - - - - - - 名师精心整理 - - - - - - - 第 2 页，共 5 页 - - - - - - - - - 第页共页单模光纤，用1.3m 激光配合使用，提供的带宽优势，增加对高数据传输率系统的中继器间距。安装光纤系统的数据传输速率最近曾迁居到千兆位每秒的范围。使用这种系统的频谱纯净的分布反馈激光器，以尽量减少光纤的色散dffects 。在1.55um 波长，对应光纤损耗最低， 低色散设计的纤维是现在常用的长距离传输。使用波长复用，以进一步增加光纤的信息容量是越来越普遍。光纤在其他领域的潜力才刚刚开始得以实现。光纤网络，计算机系统和办公室变得更prominent.In电话系统，电话系统，使用光纤互连中央办公室在首都圈和切换的层次结构中的较低水平仍在迅速增加。示范项目已被用于家庭的光纤链接。许多观察家认为，最终将升格为全国性的电话系统使用光纤处理视频带宽。这些宽带用户环路系统提供服务，如可视电话，视频娱乐的访问。普遍安装这些宽带业务将成为经济上是可行的。The single-mode fibre, used in conjunction with a 1.3 m laser, provides a bandwidth advantage which translates into increased repeater spacings for high data rate systems. Data rates for installed fiber optic systems have recently moved into gigabit per second range. Such systems use the spectrally pure distributed-feedback lasers to minimize fibre dispersion dffects. Fibres designed for low dispersion at 1.55um wavelength, which corresponds to minimum fiber loss, are now commonly used in long distance transmission. The use of wavelength multiplexing to further increase the fibre information capacity is becoming more widespread. The potential of fibre optics in other areas is only beginning to be realized. Fibre optic networks for computer systems and offices are becoming more prominent.In the telephone system, the telephone system, the use of fibre optics for interconnecting central offices within a metropolitan area and for lower levels in the switching hierarchy is still increasing rapidly. Fibre links to the home have been used in demonstration projects. Many observers believe that national telephone systems will eventually be upgraded to handle video bandwidths by using fibre optics. These wideband subscriber loop systems would provide access to services such as picturephone, video entertainment. Widespread installation of these broadband services will become economically feasible. 一、中译英光纤通信光源波长激光器色散传输介质多模光纤长途干线Optical fiber communication Light source Wavelength Laser Dispersion Transmission medium Multimode optical fiber Long distance trunk 名师资料总结 - - -精品资料欢迎下载 - - - - - - - - - - - - - - - - - - 名师精心整理 - - - - - - - 第 3 页，共 5 页 - - - - - - - - - 第页共页在美国这方面的发展程度的一个标志是在停滞的总长度纤维，估计为30.2万公里研究人员生产出第一包层玻璃光纤没有想到，使用通信单模光纤， 10.3微米的激光配合使用，提供了带宽三、答案填空1、One indication of the extent of this development is the total length of installed fiber, which was estimated to be 3.2 million kilometers in the U.S. 2、The researchers who produced the first clad glass optical fibers were not thinking of using them for communications. 3、The single-mode fibre, used in conjunction with a 名师资料总结 - - -精品资料欢迎下载 - - - - - - - - - - - - - - - - - - 名师精心整理 - - - - - - - 第 4 页，共 5 页 - - - - - - - - - 第页共页名师资料总结 - - -精品资料欢迎下载 - - - - - - - - - - - - - - - - - - 名师精心整理 - - - - - - - 第 5 页，共 5 页 - - - - - - - - -