电子信息工程专业英语B篇译文
电子信息工程作文英文翻译
电子信息工程作文英文翻译Studying electronic information engineering is like diving into a world of endless possibilities. It's all about understanding how things work, from the smallest microchip to the largest communication network. It's afield that requires both creativity and technical skills, and that's what makes it so exciting.In this field, you get to work with cutting-edge technology and be at the forefront of innovation. Whether it's developing new software, designing hardware, or improving communication systems, there's always something new and exciting to explore. It's a field that's constantly evolving, and that's what keeps it so interesting.One of the best things about electronic information engineering is the wide range of career opportunities it offers. You could work in telecommunications, computer networking, or even in the aerospace industry. There's also the option to work in research and development, where youcan be part of creating the next big technological breakthrough.But it's not just about the technical side of things. Electronic information engineering also requires strong problem-solving skills and the ability to think critically. You need to be able to analyze complex systems and come up with creative solutions to challenging problems. It's a field that's as much about thinking outside the box as itis about technical know-how.Of course, like any field, electronic information engineering also has its challenges. It can be fast-paced and demanding, and you need to be able to keep up with the latest developments in technology. But for those who are passionate about technology and innovation, it's a field that offers endless opportunities for growth and success.。
电子信息工程专业课程翻译中英文对照表
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电子信息类专业英语 李白萍编 第二版译文
第19章B 光纤通信的优点利用一根玻璃光纤引导的光载波通信有许多突出的优点，其中的一些优点在最初构思这种技术时就已经显而易见了。
然而，当今的技术发展已经超越了当初最乐观的预测，产生了另外一些优势。
因此，有必要考虑光纤通信与许多传统电子通信相比带来的优点和专业特色。
本文先介绍最初预想的优点，接着介绍随着科技发展而出现的另外的突出优点。
a）巨大的潜在带宽：频率为1013到1016 Hz（通常接近大约1014Hz红外线的频率）的光载波产生比金属电缆系统（如同轴电缆的带宽最高为500MHz）甚至毫米波无线电系统（例如系统当前工作在700MHz调制带宽）大得多的潜在传输带宽。
目前，光纤系统可以用带宽并没有被完全利用，但是，不需要中继器而传输100Km的几Ghz的调制和传输300km的几百Mhz的调制是可能的。
光纤系统的信息携带能力远优于最好的铜电缆系统。
比较而言，宽带同轴电缆系统在100Mhz以上带宽内的损耗将传输距离限制在只有几千米的范围内。
虽然可以利用的光纤带宽可以被进一步扩展到光载波频率，但是很明显这一参数（可用带宽）被单个光载波信号所限制。
因此，通过在同一个光纤中并行传输几个工作在不同的中心波长的光信号可以实现带宽利用率的很大提高。
利用波分复用技术，尤其是密集波复用（或者说，实质上的频分复用）使得光纤的信息载容量超过电缆或者宽带无线系统好多个数量级。
b）小尺寸和轻重量：光纤的直径非常小，通常比头发丝的直径还要细。
因此，就算这些光纤被涂覆层包裹时，它们都要比铜电缆直径更小并且重量更轻。
这对于缓解城市的管道拥挤而言占有很大的优势，并且允许在移动体（如飞机、卫星甚至船舶）内进行信号传输。
c）电绝缘：由玻璃或者塑料聚合物制造的光纤是电绝缘体，因此与其他对应的金属物不同，它们不存在接地循环与接口问题。
而且，该优点使得光纤十分适宜于在对电子比较敏感的危险环境中的通信，因为光纤在受侵蚀或者短路的情况下不会产生电弧或者电火花的危险。
电子信息专业英语课文翻译(部分)
电子信息专业英语课文翻译1. Chapter 1 Introduction to Electronic Technology电子技术简介1.1. Lesson 1 Development of Electronics 电子技术发展史电子技术的历史是一个关于二十世纪的故事，电子学的三个关键元件是真空管、晶体管和集成电路。
真空管也叫做电子管，它是一个密封的玻璃管，在它里面，电子在有真空隔离的电极之间流动。
在20（19×）世纪早期发明了真空管，随着真空管的发明，放大和传输电能成为可能。
电子管的第一应用在于无线电通信。
在第二次世界大战之前，随着越来越多的专门真空管被制造出来用于各种用途，通信技术从而能得到了巨大的进步。
在20世纪20年代时，无线电广播呈天文数字地增长并且成为家庭娱乐的主要来源。
电视机是在1927年发明，并且最终得到了广泛的应用。
电视机作为一种电子设备，其发展得益于在二次世界大战期间雷达上的许多进步。
雷达利用无线电微波回声来测量一个物体的距离和方向，被用于检测飞机和船只。
世界大战之后，电子管被用于开发第一台计算机，但是因为电子元件的尺寸，所以这些计算机是不切实际的。
在1947年，来自贝尔实验室的一组工程师们发明了晶体管，因为发明了晶体管，他们获得了诺贝尔奖。
晶体管的功能类似于真空管，但与真空管相比，它体积小、重量轻、消耗功率低、更加可靠和制造成本低。
在几乎所有的电子设备中晶体管取代了真空管。
在20世纪 50年代时，美国德州仪器公司发展出第一个集成电路。
第一个集成电路仅包含了几个晶体管，在随后的20世纪70年代中期，出现了大规模集成电路和超大规模集成电路。
超大规模集成电路技术允许我们在一个单芯片中构建一个包含有成千上万晶体管的系统。
摄像机、手提电话和个人电脑仅仅是集成电路使之成为可能的一些设备实例。
1.2. Lesson 2 Singapore Polytechnic 新加坡理工学院新加坡理工学院，是新加坡同类学校中的第一家教育机构，创立于1954年，学院着重培养和训练技术人员和专业人员，从而支持新加坡的工业和经济的发展。
电子信息工程专业英语英译汉翻译
1 The transistor is what started the evolution of the modern computer industry in motion.晶体管开启了现代电脑工业的革命2 The storage cell only requires one capacitor and one transistor, whereas a flip-flop connected in an array requires 6 transistors.存储单元仅需要一个电容和晶体管，并而不像触发器整列那样需要6个晶体管3 There has been a never ending series of new op amps released each year since then, and their performance and reliability has improved to the point where present day op amps can be used for analog applications by anybody.从此以后每年都有新系列的运放发布，他们的性能和可靠性得到了提升，如今任何人都能用运放来设计模拟电路。
4 This is capable of very high speed conversion and thus can accommodate high sampling rates, but in its basic form is very power hungry.它具有高速转换能力，从而能适应高速采样速率，但它的基本形式非常耗电。
5 During the “on” period , energy is being stored within the core material of the inductor in the form of flux.在”on”阶段，能量以涌浪形式存储在电感的核芯材料里面6 The design goal of frequency synthesizers is to replace multiple oscillators in a system, and hence reduce board space and cost.频率合成器的设计目标是取代系统中多个振荡器，从而减小板卡面积和成本。
最新电子信息工程专业英语课文翻译(第3版)
电子信息工程专业英语教程第三版译者：唐亦林p32In 1945 H. W. Bode presented a system for analyzing the stability of feedback systems by using graphical methods. Until this time, feedback analysis was done by multiplication and division, so calculation of transfer functions was a time consuming and laborious task. Remember, engineers did not have calculators or computers until the '70s. Bode presented a log technique that transformed the intensely mathematical process of calculating a feedback system's stability into graphical analysis that was simple and perceptive. Feedback system design was still complicated, but it no longer was an art dominated by a few electrical engineers kept in a small dark room. Any electrical engineer could use Bode's methods find the stability of a feedback circuit, so the application of feedback to machines began to grow. There really wasn't much call for electronic feedback design until computers and transducers become of age.1945年HW伯德提出了一套系统方法，用图形化方法来分析反馈系统的稳定性。
电子信息类专业英语第二版 李白萍主编十七单元译文
电子信息类专业英语第二版李白萍主编第十七单元B译文Passage B Compression/Decompression Techniques压缩/解压缩技术Numerous methods have been developed for the compression of digital image data. One of the principal drivers for this development is the television industry where quality image data must be transferred to receivers using relatively simple equipment. The development of high definition television is further focusing the attention of industry and university scientists toward problems of data reduction and digital transmission. The principal evaluation criteria for the analysis of compressed versus uncompressed imagery is whether a person can tell the difference between the images. A more implemental measure is the Root Mean Square (RMS) error between the original image and the image that has been compressed. Compression rates may be generated by determining the size of the compressed image in terms of number of bits per image pixel for the original image.[1]数字图像数据的压缩的许多方法已经开发出来。
电子信息工程专业英语课文翻译(第3版)
电子信息工程专业英语教程第三版译者:唐亦林p32In 1945 H. W。
Bode presented a system for analyzing the stability of feedback systems by using graphical methods. Until this time, feedback analysis was done by multiplication and division，so calculation of transfer functions was a time consuming and laborious task. Remember, engineers did not have calculators or computers until the ’70s。
Bode presented a log technique that transformed the intensely mathematical process of calculating a feedback system’s stability into graphical analysis that was simple and perceptive. Feedback system design was still complicated, but it no longer was an art dominated by a few electrical engineers kept in a small dark room。
Any electrical engineer could use Bode's methods find the stability of a feedback circuit，so the application of feedback to machines began to grow。
电子信息工程专业英语翻译
Cooperative Peer-to-Peer Streaming:An Evolutionary Game-TheoreticApproachYanChen,StudentMember,IEEE,BeibeiWang,StedengMember,IEEE,W.SabrinaLin,Member,IEEE,Yongle Wu,Student Member,IEEE,and K,.J.Ray Liu,Fellow,IEEE Abstrac t—While peer-to-peer(P2P)video streaming systems have achievedpromising results,they introduce a large number of unnecessary traverse links,which consequengly leads to substantial network inefficiency.To address this problem and achieve better streaming performance,we propose to enable cooperation among “group peers,”which are geographically neighboring peers with large intra-group upload and download bandwidths.C onsidering the peers’selfish nature,we formulate the cooperative streaming problem as an evolutionary game and derive,for every peer,the evolutionarily stable strategy(ESS),which is the stable Nash equilibrium and no one will deviate from.Moreover,we propose a simple and distributed learning algorithm for the peers to converge to the ESSs. ed from the peer’sown padtWith the propo sed algorithm,each peer decides whether to be an agent who downloads data from the peers outside the group or a free rider who downloads data from the agents by simply tossing a coin,where the probability of being a head for the coin is learned from the peer’s own past payoff history.Simulation results shou to the traditional non-cooperative P2P schemes,the proposed cooperative scheme achieves much better performance in terms of social welfare,probability of real-time streaming,and video quality(source rate). IndexTerms—Coopreative streaming,distributed learning,evolutionary,game theory,peer-to-peer(P2P),replicator dynamics.ⅠIntroductionWith the rapid development of signal processing,communication, and networking technologies,video-over-IP applications become more and more popular and have attracted millions of users over the Internet.One simple solution to video streaming over Internet is the client-server service model,where the video is streamed directly from a server to clients.However with the client-server service model, the upload bandwidth of the server grows proportionally with the number of clients, whice makes the large-scale video streaming impractical.To reduce the workload of the server,peer-to-peer(P2P)service model is proposed, where a peer not only acts as a client to download data from the network,but also acts as a server to upload data for the other peers in the network.The upload bandwidth of the peers reduces the workload placed on the server dramatically,which makes large-scale video streaming possible,Recently,several industrial large-scale P2P video streaming systems have been developed,includingCoolstreaming,PPLive,PPStream,UUSee,and Sopcast. Studies show that these systems can support hundreds of thousands of users simultaneously.While P2P video streaming systems have schieved promising results, they have several drawbacks. First, there are a large number of unecessary traverse links within a provider’s network.As observed in ,each P2P bit on the Verizon network,As observed in,each P2P bit on the Verizon network traverses 1000 miles and takes 5.5 metro-hops on average,Second,there is a huge number of cross Internet service provider traffic,The studies showed that 50％-90％of the existing local pieces in active peers are downloaded externally.Third,the differences in playback time among peeers can be as high as 140s,and the lag can be greater if the source rate is higher,Fourth,most of the current P2P systems assume that all peers are willing to contribute their resources.however,this assumption may mot be true since the P2P systems are self-organizing networks and the peers are selfish by nature.Note that the selfish peers will act as free-riders if being free-riders can improve their utilities.译文：对等网络流：进化论的赛局的方法杨晨，学生；王蓓蓓，学生；塞布丽娜林，IEEE成员；永乐吴，学生；永乐刘，学生摘要：而对等网络视频流系统取得了很有前途，但这样的技术引进大量不必要的导线连接,从而导致实质性的网络无效率。
电子信息类专业英语翻译
1.This electron beam sweeps across each line at a uniform rate，then flies back to scan another line directly below the previous one and so on，until the horizontal lines into which it is desired to break or split the picture have been scannedin the desired sequence．电子束以均匀的速率扫描每一行，然后飞速返回去扫描下一行，直到把被扫描的图像按所希望的顺序分割成行。
2.The technical possibilities could well exist，therefore，of nation-wide integrated transmission network of high capacity，controlled by computers，interconnected globally by satellite and submarine cable，providing speedy and reliable communications throughout the word因此，在技术上完全可能实现全国性的集成发送网络。
这种网络容量大，由计算机控制，并能通过卫星和海底电缆实现全球互联，提供世界范围的高速、可靠的通信。
3.Transit time is the primary factor which limits the ability of a transistor to operate at high frequency．渡越时间是限制晶体管高频工作能力的主要因素4.The intensity of sound is inversely proportional to the square of the distance measured from the source of the sound.声强与到声源的距离的平方成反比。
电子信息工程专业英语翻译清华出版社EnglishforITandEE03
will experience a force (in a similar way that planets
experience a force in the gravitational field of the Sun). If
电子信息工程专业英语 翻译清华出版社
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电子信息工程专业英语翻译清华出版 社EnglishforITandEE03
Unit 3
EM Fields, Antenna and Microwaves
电子信息工程专业英语翻译清华出版 社EnglishforITandEE03
two locations. For instance, the metal atoms in a radio
transmitter appear to transfer energy continuously. This view
is useful to a certain extent (radiation of low frequency), but
Part I
Electromagnetic Field
电子信息工程专业英语翻译清华出版 社EnglishforITandEE03
New Words
vicinity 邻近，附近 charge 电荷 photon 光子 atom 原子 catastrophe 大灾难，大祸 emission 发射，散发 incident 入射的 electrodynamics 电动力学 gravitational 重力的
•随着时间的推移，人们认识到 电场和磁场是电磁场这一整体 的两个部分。
电子信息工程专业英语翻译清华出版 社EnglishforITandEE03
(完整word版)电子信息工程专业英语导论B文章英文翻译第五章(word文档良心出品)
第五章电脑类型和未来发展计算机是一种电子设备，可以得到一组指令或程序，然后通过执行数值计算或编程和其他形式相关联的信息。
微机：由微电脑智能台式机或笔记本大小的计算机设备，它使用微处理器作为中央处理器，或CPU。
微型机计算机也被称为个人电脑（PC），家用电脑，小型商用电脑，微型电脑。
最小的被称为膝笔记本电脑。
当他们第一次出现，他们被视为单一的用户设备，他们第一次能够处理只有4、8或16比特的信息。
最近微型和大型计算机的区别，大型计算机以及较小型系统称为微型计算机主机）已经变得模糊，随着新微电脑机型增加了速度和数据处理能力，是他们的CPU 变成32位，甚至64位多用户范围。
小型机：小型计算机是一种中级计算机建立用来执行复杂运算而有效率地处理运算的输入和输出的高层次用户的链接通过终端。
小型机也经常可以在网络上和其他小型机链接和分布计算在所有链接设备中。
小型机是在大量使用和在交易过程应用上和作为主机系统和局域网的接口界面。
大型机：一台大型机是一个高层次的计算机被设计为了最繁重的运算任务。
大型机通常由多个用户要通过终端计算机共享。
最强大的大型机称为巨型机，执行高度复杂和耗时的计算，并大量使用在抽象和应用科学家的研究，大型企业和军队。
超级电脑：在计算机科学，超级计算机，超级大，非常快，并且是昂贵的电脑应用复杂的计算，通常情况下机器能执行流水线指令，并提供向量指令。
超级计算机可以，例如，执行数据巨大的计算，在电影中被要求制订和被模拟运动的飞船。
超级计算机也可应用气象预报，大尺度科学建模和石油商品出口。
在计算机发展的一个持续的趋势是微型化，努力将多电路压缩成越来越小的芯片空间。
研究人员还试图加快电路功能通过使用超导减少电阻的现象被看作是将物体暴露在非常低的温度下会变得更冷。
计算机网络已将成为越来越重要的计算机的发展技术。
网络大量的计算机互联通信设施连接。
公共互联网是一个全球性的计算机网络的例子。
网络连接着计算机通讯交换信息，在某些情况下，共享的工作，使更多电脑可以开展合作，执行任务。
电子信息工程专业英语翻译清华出版社EnglishforITandEE02
Collector Emitter Base
N P N
Source
Gate
N P
Drain N
Base
Collector
Emitter BJT
Gate
Drain
Source FET
Anode P N
Cathode
Anode
Cathode Diode
图2.1给出了双极型 晶体管和场效应晶 体管的图示。
从封装内伸出以便与（使用该晶 体管的）电路其余部分连接。
电子信息工程专业英语翻译清华出版 社EnglishforITandEE02
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Once you have several discrete transistors, digital logic can be built by directly wiring these components together. The circuit will function, but any substantial amount of digital logic will be very bulky, because several transistors are required to implement each of the various types of logic gates.
二极管的作用就像一个单向阀门， 由于电流只能从P流向N。
电子信息工程专业英语翻译清华出版 社EnglishforITandEE02
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Special diodes can be created that emit light when a voltage is applied. Appropriately enough, these components are called light emitting diodes, or LEDs. These small lights are manufactured by the millions and are found in diverse applications from telephones to traffic lights.
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手持单元构成市场极大的一块，它们的 手持单元构成市场极大的一块， 设计更接近于其他射频系统。 设计更接近于其他射频系统。
7
2 Cellular system
With the limited available spectrum (e.g., 25 MHz around 900 MHz), how do hundreds of thousands of people communicate in a crowded metropolitan area? To answer this question, we first consider a simpler case: thousands of FM radio broadcasting stations may operate in a country in the 88-108 88MHz band. 数十万人如何在拥挤的城区里 相互通信？ 相互通信？ 几千个FM电台可利用 几千个FM电台可利用88-108MHz 电台可利用88 的频带在一个国家里广播
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5 Co-channel interference CoAn important issue in a cellular system is how much two cells that use the same frequency interfere with each other. Called other. coco-channel interference (CCI), this effect depends on the ratio of the distance between two co-channel cells to the cell radius coand is independent of the transmitted power. 两个使用同一频率的单元 之间的干扰有多大 这一效应依赖于两个同信道单元之间的距离 与单元半径之比，而与发射功率无关。 与单元半径之比，而与发射功率无关。
电子信息工程专业英语导论B文章英文翻译第一章
第一章电能是怎样产生的电能是电子和电荷的流动。
它是一种二次能源来源。
也就是说，我们从其他能源的转换得到它。
如煤炭，天然气，石油，核能和其他天然来源，这是所谓的主要来源。
电力发电机是一种将机械能转换成电能的能源装置。
该过程是基于磁和电之间的关系。
当电线或任何其他导电材料在磁场中移动，电线中就产生电流。
在电力工厂中使用大型发电机组有一个固定的指挥。
一附着在旋转轴端的磁铁是定位在一个固定的导电环内，是被一个长的，连续的线片包裹着。
当磁铁旋转时，它在它通过的任何部分都感应出小电流。
导线的每一个部分构成一个小的、独立的电导体。
所有各自部分的小电流加起来构成了一个颇具规模的电流。
这个电流应用于电力。
电力发电站使用的涡轮、引挚、水车或其他类似机器来驱动发电机的一个转换设备将机械能或化学能转换为电能。
蒸汽机、内燃机，燃气涡轮机，水涡轮机，风力涡轮机是最常用产生电力的方法。
大多数电力工厂的效率约35%。
这意味着没100能源只有35各单位被转换成可用电能。
美国大部分的电力汽涡轮机生产的，涡轮将流体的功能转换成机械能。
蒸汽涡轮机有一系列刀片安装在一个抵抗蒸汽压力的轴上。
从而旋转轴连接到发电机。
在化石燃料的蒸汽涡轮中燃烧加热水使其煮沸产生蒸汽。
煤炭，石油，天然气在大的燃烧炉中燃烧加热水使蒸汽反过来推动涡轮机的叶片。
在美国，煤炭是最大的单一能源的主要来源用于生成店里。
在我国，超过全国一半电力是用煤作为它的能量来源。
天然气，除了被燃烧加热产生水蒸气，也可以燃烧产生热燃烧气体直接通过涡轮旋转的涡轮叶片一发电。
当电力公司有高需求时通过使用燃烧汽轮机，一种民族的电力部分是加剧了天然气石油还可以用来制造蒸汽使涡轮机转动。
剩余燃油通常，一种从原油中提炼的产品，通常这些石油工厂被电厂用他们来制造蒸汽。
我们国家大约3%-4%的电力生产是靠石油来生产的。
核电是一种通过核裂变的过程加热水产生蒸汽的方法。
在核电厂，核反应堆包含了核心燃料，主要是浓缩铀。
专业英语（电子与信息工程类）翻译
专业英语（电子与信息工程类）翻译1.As data networks advanced…also grew more complex.由于数据网络从面向终端的系统向分组交换、计算机与计算机连接的方向发展，执行网络功能所必需的协议也变得愈来愈复杂。
2.An additional bit called a parity bit…during transmission.在每个字符的后面有时还包括一个称为奇偶校验位的附加位，它们测试数据位在传输过程中是否被意外改变。
3.As already stated，with…downlink（FDD paired bands）.如前所述，在非对称通信量应用中，TD-SCDMA利用可用频谱的效率比其他3G 标准高，因为它在只利用一个频带（TDD单一频带）而不是两个独立的频带（FDD成对频带）进行上行及下行通信。
4.Although often simpler to implement，…digital modulation.虽然光纤系统的模拟调制易于实现，但其效率较低，且要求在接收端有比数字调制高得多的信噪比。
5.At present，the bandwidth…electronics （）is possible.目前传输100km的几吉赫兹的调制信号和传输300km的几百兆赫兹的调制信号都是可能的，因此光纤系统的可用带宽并没有得到充分利用。
6.Both TD-SCDMA deployments-TSD…unpaired bands awarded.TD-SCDMA的两种部署——TSM和TDDCLR的数据速率、频谱利用率、覆盖率、移动性和可靠性等性能是一样的，并基本上为所有取得非成对TDD频段牌照的运营商所采用。
7.Crossbar switching was carried…selection for all calls.纵横制交换由一个称为标志器的特定电路控制，标志器提供整个号码的公共控制并选择所有呼叫的路由。
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果粒橙图解:译文“蓝色”Unit 6 The Principle of PCMPCM原理Pcm is dependent on three separate operations, sampling, quantizing, and coding. Many different schemes for performing these three functions have evolved during recent years, and we shall describe the main ones. In these descriptions we shall see how a speech channel of telephone quality may be conveyed as a series of amplitude values, each value being represented, that is, coded as a sequence of 8 binary digits. Furthermore, we shall prove that a minimum theoretical sampling frequency of order 6.8 kilohertz(khz) is required to convey a voice channel occupying the range 300 HZ to 3.4 Khz. Practical equipments, however, normally use3 a sampling rate of 8 khz, and if 8-digits per sample value are used, the voice channel becomes represented by a stream of pulses with a repetition rate of 64khz. Fig .1-1 illustrates the sampling, quantizing, and coding processes.PCM的构成依赖于三个环节，即采样、量化和编码。
近年来，人们对这三个环节的实现提出了许多不同的方案，我们将对其中的一些主要的方案进行讨论。
在这些讨论中，我们会看到话路中的语声信号是如何转换成幅值序列的，而每个幅值又被编码，即以8位二进制数的序列表示。
而且，我们将证明，为了转换频率范围为300HZ—3.4KHZ的话路信号，理论上最小采样频率须为6.8khz。
但是，实际设备通常用8khz的采样速率，而如果每个样值用8位码的话，则话路是由一个重复速率为64khz的脉冲流来表示的。
图1-1表示了采样、量化、编码的过程。
Reexamination of our simple example shows us that the speech signal of maximum frequency 3.4khz has been represented by a signal of frequency 64khz. However, if only 4-digits per sample value had been used, the quality of transmission would drop, and the repetition rate of the pulses would be reduced to 32khz. Thus the quality of transmission is dependent on the pulse repetition rate, and for digital communication systems these two variables may be interchanged most efficiently.让我们再研究一下上面提到的简单例子。
可以看出，最高频率为3.4khz的话音信号适用64khz的（脉冲流）信号来表示的。
但是，如果每个样值中用4位（码）表示，则传输质量会下降，而脉冲的重复速率也将减小到32khz。
因而传输质量是取决于脉冲重复速率的。
对于数字通信系统，这两个量之间极明显的互相影响着。
Digital transmission provides a powerful method for overcoming noisy environments. Noise can be introduced into transmission patch in many different ways : perhaps via a nearby lightning strike, the sparking of a car ignition system, or the thermal low-level noise within the communication equipment itself. It is the relationship of the true signal to the noise signal, known as the signal-to-noise ratio, which is of the most interest to the communication engineer.Basically, if the signal is very large compared to the noise level, then a perfect message can take place; however, this is not always the case. For example, the signal received from asatellite, located in far outer space, is very weak and is at a level only slightly above that of the noise. Alternative examples may be found within terrestrial systems where, although the message signal is strong, so is the noise power.数字传输对于克服噪声环境的影响提供了一个强有力的手段。
噪声可以以多种不同方式进入传输信道，比如说因为附近的闪电、汽车点火系统的打火或因通信设备本身低电平的热噪声所致。
正是这种被称为信噪比的东西，即真实信号与噪声的关系引起了通信工程师的极大的兴趣。
从本质上讲，如果信号比噪声电平大得多，则信息的传输是完美的。
但是，实际情况并不总是这样，例如，从位于遥远太空中的卫星接收到的信号极其微弱，其电平仅比噪声稍高一点。
地面系统则是另一类例子，尽管信号很强，噪声也很强。
If we consider binary transmission, the complete information about a particular message will always be obtained by simply detecting the presence or absence of the pulse. By comparison, most other forms of transmission systems convey the message information using the shape, or level of the transmitted signal; parameters that are most easily affected by the noise and attenuation introduced by the transmission path. Consequently there is an inherent advantage for overcoming noisy environments by choosing digital transmission.研究二进制信号的传输可见，只要简单的区判别脉冲的有和无，完美就获得了一条消息的全部信息。
相比之下，许多其他形式的传输系统是利用被传信号的波形或电平的高低来传送信息的，而这些参数又极易受到传输途径中的噪声和衰耗的影响。
因此选择数字传输系统在克服噪声环境的影响方面有其固有的优势。
So far in this discussion we have assumed that each voice channel has a separate coder, the unit that converts sampled amplitude values to a set of pulses; and decoder, the unit that performs the reverse operation. This need not be so, and systems are in operation where a single codec (i.e., coder and its associated decoder) is shared between 24, 30, or even 120 separate channels.A high-sped electronic switch is used to present the analog information signal of each channel, taken in turn, to the codec. The codec is then arranged to sequentially sample the amplitude value, and code this value into the 8-digit sequence. Thus the output to the codec may be seen as a sequence of 8 pulses relating to channel 1, then channel 2, and so on. This unit is called a time division multiplexer (TDM), and is illustrated in fig. 1-2. The multiplexing principle that is used is known as work interleaving. Since the words, or 8-digit sequences, are interleaved in time.到目前为止，在这个讨论中，我们一直假定每个话路各有一个编码器和解码器。