通信专业英语复习资料

1、Unit【中译英】(1) 信号:signal (2) 波特率:the baud rate (3) 单工:simplex (4) 同步:synchronous (5) 信道:communications channel(6) 模拟:analog (7) 数字:digital (8) 电磁的:electromagnetic (9) 串行口:serial port (10) 带宽:bandwidth【英译中】(1) baud:波特(2) asynchronous:异步的(3) full duplex:全双工(4) parallel:并行 (5) electromagnetic:电磁的(6) disc

2、rete:离散的(7) simultaneously:同时发生地(8) parity:奇偶校验【句子翻译（英译中）】1. Since transmitted data can be assigned to different frequencies,the wider the bandwidth,the more the frequencies,and the more data can be transmitted at the same time.因为传输的数据能被分配到不同频率，所以带宽越宽频率越多，同一时间能被传输的数据就越多。2. To distinguish where one c

3、haracter stops and another starts,the asynchronous communication mode uses a start and a stop bit.为了辨别一个字符在什么地方结束而另一个字符在什么地方开始，异步通信模式使用一个起始位和一个结束位。3. More technical manes for the serial port are RS-232C connector and asynchronous communication port.串行端口技术上又叫做RS-232C连接器和异步通信接口。【段落翻译（英译中）】v The third

4、is the transmission mode. Transmission modes include the asynchronous mode and the synchronous mode. In the asynchronous transmission mode, individual characters (made up of bits) are transmitted at irregular intervals, for example. When a user enters data. To distinguish where one character stops a

5、nd another starts, the asynchronous communication mode uses a start and a stop bit. An additional bit called a parity bit is sometimes included at the end of each character. Parity bits are used for error checking. The asynchronous transmission mode is used for lower speed data transmission and is u

6、sed with most communication equipment designed for personal computers. 第三是传输模式。传输模式包括异步和同步。在异步传输模式中，单独的字符(由比特组成)以不规则的时间间隔传输，例如当用户输入数据时。为了辨别一个字符在什么地方停止而另一个字符在什么地方开始，异步通信模式使用一个起始位和一个停止位。一个称为奇偶位的附加位有时包含在每个字符的末端。奇偶位用于错误校验。异步传输模式用于低速数据传输以及用在设计适合个人计算机的大多数的通信设备中。Unit3【中译英】（1）载波：Carrier Frequencies（2）多路复用：M

7、ultiplexing（3）载波振荡频率：the frequency at which the stations carrier oscillates （4）频分复用：Frequency Division Multiplexing （5）旋转开关：round-robin scheme （6）时分复用：Time Division Multiplexing【缩写翻译】 FDM：Frequency Division Multiplexing 频分复用 TDM：Time Division Multiplexing 时分复用【句子翻译（英译中）】（1） In fact，a channel number

8、is merely shorthand for the frequency at which the stations carrier oscillates. 实际上，频道号码就是电视台载波用的振荡频率的速记。（2） A receiver configured to accept a carrier at a given frequency will not be affected by signal sent at other frequencies. 一个接收器被设置成接收给定频率的载波，它将不会受其他频率信号的影响（或干扰）。（3） Frequency Division Multiple

9、xing(FDM) is the technical term applied to a network system that uses multiple carrier frequencies to allow independent signals to travel through a medium.频分复用（FDM）是使用多个载波频率在一个介质中同时传输多个独立信号的计算机网络系统术语。（4） In practice, however, two carriers operating at almost the same frequency or at exact multiples

10、of a frequency can interfere with one another.实际上，两个频率相近或频率成整数倍的载波会彼此干扰。（5） The mandate for large gape between the frequencies assigned to carriers means that underlying hardware used with FDM can tolerate a wide range of frequencies.在各载波的频率之间的大间隔意味着FDM所用的硬件能容纳很宽的频率范围。（6） The general alternative to

11、FDM is time division multiplexing(TDM), in which sources sharing a medium take turns.与FDM不同的另一种复用形式是时分多路复用（TDM），按这种方式各发送源轮流使用共享的通信介质。【段落翻译（英译中）】v Dividing data into small packets ensures that all sources receive prompt service because it prohibits one source from gaining exclusive access for an arbi

12、trarily long time. In particular, if one source has a few packets to send and the other has many, allowing both sources to take turns sending packets which guarantees that the source with a small amount of data will finish promptly.将数据分成小包以确保所有的信源都能得到及时服务，因为这时是禁止一个信源获取一个独占的长时服务。尤其是，如果一个信源需要发送的数据包数量较

13、少，而另一个信源需要发送的数据包较多时，采用时间片轮转方式使两个信源轮流发送数据包以确保数据包较少的信源的数据发送能及时完成。Unit4【中译英】(1) 电磁波:Electromagnetic wave (2) 同轴电缆:Coaxial cable (3) 双绞线:twisted-pair wire(4) 微波系统:Microwave system (5) 同步卫星:Satellite system (6) 无线电波饱和度:the saturation of the airwaves【英译中】(1) unsheathed:无覆盖的 (2) insulator:绝缘体 (3) susceptib

14、le:易受影响的 (4) vicinity:邻近地区 (5) curvature:曲度(6) antenna:天线 (7) gigahertz:千兆赫 (8) nonconductive:不传导的【句子翻译（英译中）】（1） The form or method of communications affects the maximum rate at which data can be moved through the channel and the level of noise that will exist.通信的形式或方法决定着数据可以通过信道传输的最大速度以及会出现的噪声等级.（2

15、） Obviously，some situations require that data be moved as fast as possible, others dont.显然，有时要求数据传输得越快越好，有时则不然。（3） Understanding how these media function will help you sort out the various rates and charges for them and determine which is the most appropriate in a given situation.理解这些媒介的性能将帮助你区别不同的速

16、率和费用并决定在一个特定的情况下哪一种是最适合的。（4） . which limits the practical distance that data can be transmitted without being garbled.这限制了数据不失真传输的实际距离。（5） To be received intact, digital signals must be “refreshed” every one to two miles through the use of an amplifier and related circuits, which together are called

17、 repeaters.数字信号想要完整接收，必须每12英里用放大器及相关电路重新放大，这种放大装置称为增音器。（6） The distance between the towers depends on the curvature of the surface terrain in the vicinity.两座塔之间的距离取决于附近地表的弯曲程度。（7） Each tower facility receives incoming traffic, boots the signal strength, and sends the signal to the next station.每个塔上的

18、设备接收过来的信号，加以放大，并把信号发送到下一个基站。（8） However. The saturation of the airwaves with microwave transmissions has reached the point where future needs will have to be satisfied by other communications methods, such as fiber optic cables or satellite systems.但是，当传输微波的空气波达到饱和状态时，必须要有其他方式来满足将来的需要，例如光纤和卫星系统。【段落翻

19、译（英译中）】Instead of using wire or cables, microwave systems can use the atmosphere as the medium through which to transmit signals. These systems are extensively used for high-volume as well as long-distance communication of both data and voice in the form of electromagnetic waves similar to radio wav

20、es but in a higher frequency range. Microwave signals are often referred to as “line of sight” signals because they cannot bend around the curvature of the earth. Instead, they must be relayed from point to point by microwave towers, or relay stations, placed 20 to 30 miles apart. The distance betwe

21、en the towers depends on the curvature of the surface terrain in the vicinity. The surface of the earth typically curves about 8 inches every mile. The towers have either a dish or a horn-shaped antenna. The size of the antenna varies according to the distance signals must cover. A long-distance ant

22、enna could easily be 10 feet or larger in size and a dish of 2 to 4 feet in diameter, which you often see on city buildings, is large enough for small distances. Each tower facility receives incoming traffic, boots the signal strength, and sends the signal to the next station. 和用导线及电缆不同，微波系统用大气作为媒介，

23、据此传输信号。这些系统主要用于大批量及长距离的数据和话音通信，类似于无线电波，但频率范围更高。微波信号通常是直线信号，因为它们不能随地球的弯曲而弯曲；相反，它们必须由微波塔或每2030英里设置的中继站实现点到点的转发。两座塔之间的距离取决于附近地表的弯曲程度。地球表面一般说来每英里弯曲8英寸。微波塔有一个截抛物面天线或一个圆锥形天线。天线的长度随信号需要覆盖的范围而变化。一个长距离天线可达10英尺或更长；直径在2-4英尺的截抛物面天线对于短距离的转发也就足够了，这种天线在城市建筑物顶上能经常看到。每个塔上的设备接收过来的信号，加以放大，并把信号发送到下一个基站。Unit7【中译英】(1) 光纤

24、：Fiber optic (2)光脉冲：The pulses of light (3)单模光纤：single mode Optical Fiber (4) 多模光纤：multimode Optical Fiber (5)塑料光纤：Plastic Optical Fiber (POF)【句子翻译（英译中）】(1)A fiber looks like a common glass cylinder consisting of core and cladding regions.光纤看上去像一普通玻璃圆柱体，由纤芯和包层组成。(2) A single mode cable is made up of

25、 one or a number of quartz fibers with a diameter of 8.3 m to 10 m that has one mode of transmission.单模光缆由直径为8.3微米至10微米的一条或若干条光线组成，并且只以一种模式进行传输 (3) The step index multimode was the first fiber designed but is too slow for most uses,due to the dispersion caused by the different path lengths of the va

26、rious modes.阶跃型多模光纤是首先光线产品，但由于存在多个不同路径长度引起的模式色散从而使得它在大多数的使用中传输速率太低。 (4) The graded index multimode fiber, as the name implies, the refractive index of this fiber gradually decreases from the core out through the cladding to compensate for the different path lengths of the modes.渐变型多模光纤正如其名，它的折射率从纤芯到

27、包层逐渐减小，以弥补不同路径长度造车你给的模式色散。【段落翻译（英译中）】By contrast, a multimode fiber has a core diameter that is much large than the wavelength of light transmitted. (The most common size is 62.5 m). Light waves are dispersed into numerous paths, or modes, as they travel through the cables core typically 850 nm or 1

28、300 nm. However, in long cable runs( greater than 3000 m), multiple paths of light can cause signal distortion at the receiving end, resulting in an unclear and incomplete data transmission.与单模光纤相反，多模光纤的纤芯直径远大于传输光波的波长(常用的芯径为625gm)。光波在光缆纤芯中传输时的典型波长为850nm或1300nm并被分散成众多的路径和模式。然而，在长距离光缆(超过3000m)传输时，多个路径

29、的光波会在接收端造成信号扭曲、失真，并导致传输数据的不清晰和不完整。Unit8【中译英】(1) 数字同步系列：SDH (Synchronous Digital Hierarchy) (2)光纤通信网络：optical telecommunication network(3) 同步复用器：synchronous multiplexers (4)网络节点接口：Network Node Interface (NNI)(5) 线路终端复用器：Line Terminal Multiplexer (LTM) (6)分插复用器：Add-drop Multiplexer (ADM)【缩写翻译】SDH：Sync

30、hronous Digital Hierarchy 数字同步系列 | LTM：Line Terminal Multiplexer 线路终端复用器ADM：Add-drop Multiplexer 分插复用器【句子翻译（英译中）】(1) It brings out a revolution in telecommunications transmission system.它是电信传输体制的一次革命。 (2) The objective was to produce a worldwide standard for synchronous transmission systems which pr

31、ovides network operators with a flexible and economic network.他们的目标是为同步传输系统制定一个世界通用的标准，以期向网络运营者提供更具灵活性和经济性的网络。 (3) In addition to defining standards covering the NNI, CCITT also embarked on series of standards governing the operation of synchronous multiplexers(G.781,G.782 and G.783) and SDH network

32、 management (G.784).除定义了NNI有关的标准外，CCITT还着手制定了决定着同步复用设备的运行(G.781,G.782 和 G.783)以及SDH网络管理（G.784）的一系列标准。(4) The SDH standards are based on the principles of direct synchronous multiplexing which is the key to cost-effective and flexible telecommunication networking.SDH标准的基础是直接同步复用，这是低价高效和灵活组网的关键。 (5) A

33、pproximately 5% of the SDH signal structure is allocated to supporting advanced network management procedures and practices.SDH信号结构中有近5%被用于支持先进的网络管理程序和操作规程。 (6) Line Terminal Multiplexer (LTM): LTM can accept a number of tributary signals and multiplex them to the appropriate optical SDH rate carrie

34、r, i. e STM-1, STM-4 or STM-16.线路终端复用器（LTM）：LTM可接受一批支路信号并将它们复用至适当的SDH速率的光载体上，即STM-1,STM-4或STM-16。(7) Add-drop Multiplexer (ADM): a particular type of terminal multiplexer designed to operate in a through mode fashion.分插复用器（ADM）：一种特殊类型的终端复用单元，它是以“贯通”模式运行的。 (8) Almost all new fiber-transmission system

35、s now being installed in public networks use SDH or SONET.目前几乎所有应用在公众网上的新的光纤传输系统都使用了数字同步系列或同步光纤网。Unit9【中译英】 1光纤到家： Fiber To The Home (FTTH)2可靠的语音服务和高质量的视频服务：dependable voice and high-quality video service. 3光电转换器：Electrical Converter (OEC) 4双绞线：Twisted pair5电影品质的视频会议和电视电话：picture-quality videoconfer

36、encing, and videophones6用户数字线路：Digital Subscriber Line (DSL)7互动式电视：interactive television 8高速互联网接入：high-speed Internet access9互动双向视频服务：interactive two-way video-based services 10直播卫星电视Direct Broadcast Satellite (DBS) television【英译中】1High-speed data service:高速数据传输服务 2Signal fiber:单芯光缆3Broadcast cable

37、 television:直播有线电视4Coax and Hybird Fiber/Coax (HFC) networks：同轴电缆和混合光纤同轴网络5Cable modems:电缆调制解调器6DC power network:直流电源网络.7Public Switched Telephone Network(PSTN): 公共交换电话网8Standard user interfaces:标准用户接口【缩写翻译】 FTTH：Fiber to the Home 光纤到家 WDM：Wavelength Division Multiplexing 波分复用器【句子翻译】（书P43，有点多）Unit10

38、【中译英】(1)全球通信骨干网：The global telecommunications and networking backbone(2)波分复用：Wavelength Division Multiplexing(3)光脉冲：Pulses of light on fiber(4) 调频无线信道：FM radio channels(5) 多模畸变：multimode distortion.(6) 单模玻璃光纤：single-mode glass fiber【句子翻译（英译中）】(1) One reason is that a single converter from electrical

39、 to optical signals can only make use of a small amount of optic spectrum, limiting the achievable bandwidth to about 2.5 gigabits per second.一个主要的原因是一台从电信号到光信号的单项转换器只利用很少的光谱就可以把可达到的带宽限制到大约每秒2.5兆位 (2) With the use of WDM, the capacity of a single strand of fiber, 250 micros in diameter, can carry be

40、tween 10 and 80 Gbps.使用WDM，直径为250微米的单股光线的信息载量可在10至80Gpbs之间,. (3) . while repeaters on a fiber-optic cable can be spaced up to 30 km.光缆上的中继器（转发器）可以每隔最多30公里放一只。 (4) .often made of plastic, that can be driven by cheap light-emitting diodes, while long distance connections use the more expensive single-

41、mode glass fiber, driven by lasers.这些光纤通常由塑料做成，可由便宜的发光二极管驱动；而长距离的链接使用更为昂贵的单模玻璃光纤，由激光驱动。Unit23【中译英】(1) 局域网协议：Local Area Networks Protocols (2)令牌总线：Token Bus (3)以太网：Ethernet(4)冲突：Collision (5)令牌环：Token ring【缩写翻译】 LAN:Local Area Networks 局域网 LLC: Logical link Control 逻辑链路控制层 MAC: Media Access Control 媒

42、体访问控制层 FDDI: Fiber distributed data interface 光纤分布式数据接口【句子翻译（英译中）】(1) Although 802.3 is widely used in offices, during the development of the 802 standard, people from General Motors and other companies interested in factory automation had serious reservations about it.虽然802.3被广泛应用于办公室，但在802标准发展期间，来

43、自通用汽车和其他公司的对工厂自动化感兴趣的人们严重地限制了它的使用。 (2) In other words, it is easy to calculate the maximum time that will pass before a device has the opportunity to send data.换句话说，它容易计算一个设备在有机会传送数据之前所经过的最大限度的时间。Unit24 TCP/IP：Transmission Control Protocol/Internet Protocol 因特网协议（传输控制协议/网际协议）【句子翻译（英译中）】(1) The Inter

44、net is closely tied with a communications protocol system called TCP/IP, which stands for Transmission Control Protocol/Internet Protocol.因特网与TCP/IP通信协议组密切相关，TCP/IP指的是传输控制协议/网际协议。 (2) The purpose of the network layer is to send source packets from any network on the inter-network and have them arriv

45、e at the destination independent of the path and networks they took to get there.互联层的目的是由互联网络上任意网络发出源数据包并将它们送至信宿，而与到信宿所走的路由和网络无关。 (3) In contrast, networks typically arent built with the OSI protocols, although the OSI model is used as a guide.与之相反，尽管OSI模型是一个典范，但以OSI协议所建设的网络却不典范。Unit25 WAP：Wireless

46、Application Protocol 无线应用协议【句子翻译（英译中）】(1) WAP, short for Wireless Application Protocol, is a series of standard combinations similar to Internet application in developing mobile network.WAP是无线应用协议的简称，它是开发移动网络上类似互联网应用的一系列规范的组合。 (2) .but its specifical for the optimization of small screen, narrowband

47、users of devices(such as mobile phones).但专为小屏幕、窄带的用户装置（如移动电话）进行优化。 (3) The past few years have witnessed a radical shift in the way we work, play, and communication.过去几年已表明，我们工作、消遣和通信的方式已发生了根本改变。 (4) At the same time, people around the world have jumped to wireless communications at a frenzied pace.

48、同时，全世界的人们转向到对无线通信疯狂的地步。 (5) In addition, services geared to the mobile environment can push critical information such as news and stock price alerts asynchronously to the user.另外，与移动环境相适应的服务可以将新闻、股票等关键信息异步推送给用户。 (6) A failure to do so could eventually translate into the loss of a significant percent

49、age or available traffic. 不这样做的话，最终可能会失去大量的可用信息。(7) Conversely, exploitation of the mobile Internet(as enabled by WAP) creates opportunities to reach new customers, provide more personalized service, and sell new applications.相反，移动互联网的开发（WAP使之能实现）给新用户创造各种机会，提供更加个性化的服务和销售心的应用程序。 附录1：第一单元课文翻译通信是人类固有需求

50、的一部分，人类一开始就使用不同的技术和方式进行交流，而环境 和可利用的技术也限定了人类通信的方法和方式。数据通信涉及到在通信双方传递信息.现在我们共同来学习关于数据通信的基本知识.l 信号1信号和0信号不能这样通过网络链路传送。它们必须进一步被转换成传输介质能够接受的形式。传输介质通过沿着一条物理线路传输能量来工作。所以，一个1信号和0信号的数据流必须被转换为电磁信号形式的能量。l 模拟和数字数据和代表它们的信号都能够采用模拟的或者数字的形式。模拟涉及连续的某些事物一一一组特殊点的数据以及各点之间所有可能的点。数字涉及离散的某些事物。信息能够是模拟的或数字的。模拟信息是连续的。数字信息是离散的。信号可以是模拟的或数字的。模拟信号在一个范围内可以有任何值：而数字信号仅有有限数量的值。l 信道的特性首先是传输率。一个信道的传输率是由它的带宽和速度决定的。带宽是一个通道能够支持的频率范围。因为传输的数据能被分配到不同频率，所以带宽越宽频率越多，同一时间能被传输的数据就越多。传输数据的速度通常以每秒多少比特或以波特率来表示。每秒比特(bps)是在一秒内能被传输的比特数。波特率是被传输的信号每秒变化的次数。一般地，仅当1比特以一个信号变化被传输时，每秒比特和波特率才是相同的。第二是传输方向。数据传输方向被分为单