通信專業(yè)英語復(fù)習(xí)資料

1、Unit【中譯英】(1) 信號:signal (2) 波特率:the baud rate (3) 單工:simplex (4) 同步:synchronous (5) 信道:communications channel(6) 模擬:analog (7) 數(shù)字:digital (8) 電磁的:electromagnetic (9) 串行口:serial port (10) 帶寬:bandwidth【英譯中】(1) baud:波特(2) asynchronous:異步的(3) full duplex:全雙工(4) parallel:并行 (5) electromagnetic:電磁的(6) disc

2、rete:離散的(7) simultaneously:同時發(fā)生地(8) parity:奇偶校驗【句子翻譯（英譯中）】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.因為傳輸?shù)臄?shù)據(jù)能被分配到不同頻率，所以帶寬越寬頻率越多，同一時間能被傳輸?shù)臄?shù)據(jù)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.為了辨別一個字符在什么地方結(jié)束而另一個字符在什么地方開始，異步通信模式使用一個起始位和一個結(jié)束位。3. More technical manes for the serial port are RS-232C connector and asynchronous communication port.串行端口技術(shù)上又叫做RS-232C連接器和異步通信接口?！径温浞g（英譯中）】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. 第三是傳輸模式。傳輸模式包括異步和同步。在異步傳輸模式中，單獨的字符(由比特組成)以不規(guī)則的時間間隔傳輸，例如當(dāng)用戶輸入數(shù)據(jù)時。為了辨別一個字符在什么地方停止而另一個字符在什么地方開始，異步通信模式使用一個起始位和一個停止位。一個稱為奇偶位的附加位有時包含在每個字符的末端。奇偶位用于錯誤校驗。異步傳輸模式用于低速數(shù)據(jù)傳輸以及用在設(shè)計適合個人計算機的大多數(shù)的通信設(shè)備中。Unit3【中譯英】（1）載波：Carrier Frequencies（2）多路復(fù)用：M

7、ultiplexing（3）載波振蕩頻率：the frequency at which the stations carrier oscillates （4）頻分復(fù)用：Frequency Division Multiplexing （5）旋轉(zhuǎn)開關(guān)：round-robin scheme （6）時分復(fù)用：Time Division Multiplexing【縮寫翻譯】 FDM：Frequency Division Multiplexing 頻分復(fù)用 TDM：Time Division Multiplexing 時分復(fù)用【句子翻譯（英譯中）】（1） In fact，a channel number

8、is merely shorthand for the frequency at which the stations carrier oscillates. 實際上，頻道號碼就是電視臺載波用的振蕩頻率的速記。（2） A receiver configured to accept a carrier at a given frequency will not be affected by signal sent at other frequencies. 一個接收器被設(shè)置成接收給定頻率的載波，它將不會受其他頻率信號的影響（或干擾）。（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.頻分復(fù)用（FDM）是使用多個載波頻率在一個介質(zhì)中同時傳輸多個獨立信號的計算機網(wǎng)絡(luò)系統(tǒng)術(shù)語。（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.實際上，兩個頻率相近或頻率成整數(shù)倍的載波會彼此干擾。（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.在各載波的頻率之間的大間隔意味著FDM所用的硬件能容納很寬的頻率范圍。（6） The general alternative to

11、FDM is time division multiplexing(TDM), in which sources sharing a medium take turns.與FDM不同的另一種復(fù)用形式是時分多路復(fù)用（TDM），按這種方式各發(fā)送源輪流使用共享的通信介質(zhì)。【段落翻譯（英譯中）】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.將數(shù)據(jù)分成小包以確保所有的信源都能得到及時服務(wù)，因為這時是禁止一個信源獲取一個獨占的長時服務(wù)。尤其是，如果一個信源需要發(fā)送的數(shù)據(jù)包數(shù)量較

13、少，而另一個信源需要發(fā)送的數(shù)據(jù)包較多時，采用時間片輪轉(zhuǎn)方式使兩個信源輪流發(fā)送數(shù)據(jù)包以確保數(shù)據(jù)包較少的信源的數(shù)據(jù)發(fā)送能及時完成。Unit4【中譯英】(1) 電磁波:Electromagnetic wave (2) 同軸電纜:Coaxial cable (3) 雙絞線:twisted-pair wire(4) 微波系統(tǒng):Microwave system (5) 同步衛(wèi)星:Satellite system (6) 無線電波飽和度:the saturation of the airwaves【英譯中】(1) unsheathed:無覆蓋的 (2) insulator:絕緣體 (3) susceptib

14、le:易受影響的 (4) vicinity:鄰近地區(qū) (5) curvature:曲度(6) antenna:天線 (7) gigahertz:千兆赫 (8) nonconductive:不傳導(dǎo)的【句子翻譯（英譯中）】（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.通信的形式或方法決定著數(shù)據(jù)可以通過信道傳輸?shù)淖畲笏俣纫约皶霈F(xiàn)的噪聲等級.（2

15、） Obviously，some situations require that data be moved as fast as possible, others dont.顯然，有時要求數(shù)據(jù)傳輸?shù)迷娇煸胶?，有時則不然。（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.理解這些媒介的性能將幫助你區(qū)別不同的速

16、率和費用并決定在一個特定的情況下哪一種是最適合的。（4） . which limits the practical distance that data can be transmitted without being garbled.這限制了數(shù)據(jù)不失真?zhèn)鬏數(shù)膶嶋H距離。（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.數(shù)字信號想要完整接收，必須每12英里用放大器及相關(guān)電路重新放大，這種放大裝置稱為增音器。（6） The distance between the towers depends on the curvature of the surface terrain in the vicinity.兩座塔之間的距離取決于附近地表的彎曲程度。（7） Each tower facility receives incoming traffic, boots the signal strength, and sends the signal to the next station.每個塔上的

18、設(shè)備接收過來的信號，加以放大，并把信號發(fā)送到下一個基站。（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，當(dāng)傳輸微波的空氣波達(dá)到飽和狀態(tài)時，必須要有其他方式來滿足將來的需要，例如光纖和衛(wèi)星系統(tǒng)?！径温浞?/p>

19、譯（英譯中）】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 “l(fā)ine 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. 和用導(dǎo)線及電纜不同，微波系統(tǒng)用大氣作為媒介，

23、據(jù)此傳輸信號。這些系統(tǒng)主要用于大批量及長距離的數(shù)據(jù)和話音通信，類似于無線電波，但頻率范圍更高。微波信號通常是直線信號，因為它們不能隨地球的彎曲而彎曲；相反，它們必須由微波塔或每2030英里設(shè)置的中繼站實現(xiàn)點到點的轉(zhuǎn)發(fā)。兩座塔之間的距離取決于附近地表的彎曲程度。地球表面一般說來每英里彎曲8英寸。微波塔有一個截拋物面天線或一個圓錐形天線。天線的長度隨信號需要覆蓋的范圍而變化。一個長距離天線可達(dá)10英尺或更長；直徑在2-4英尺的截拋物面天線對于短距離的轉(zhuǎn)發(fā)也就足夠了，這種天線在城市建筑物頂上能經(jīng)?？吹健Ｃ總€塔上的設(shè)備接收過來的信號，加以放大，并把信號發(fā)送到下一個基站。Unit7【中譯英】(1) 光纖

24、：Fiber optic (2)光脈沖：The pulses of light (3)單模光纖：single mode Optical Fiber (4) 多模光纖：multimode Optical Fiber (5)塑料光纖：Plastic Optical Fiber (POF)【句子翻譯（英譯中）】(1)A fiber looks like a common glass cylinder consisting of core and cladding regions.光纖看上去像一普通玻璃圓柱體，由纖芯和包層組成。(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.單模光纜由直徑為8.3微米至10微米的一條或若干條光線組成，并且只以一種模式進(jìn)行傳輸 (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.階躍型多模光纖是首先光線產(chǎn)品，但由于存在多個不同路徑長度引起的模式色散從而使得它在大多數(shù)的使用中傳輸速率太低。 (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.漸變型多模光纖正如其名，它的折射率從纖芯到

27、包層逐漸減小，以彌補不同路徑長度造車你給的模式色散?！径温浞g（英譯中）】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.與單模光纖相反，多模光纖的纖芯直徑遠(yuǎn)大于傳輸光波的波長(常用的芯徑為625gm)。光波在光纜纖芯中傳輸時的典型波長為850nm或1300nm并被分散成眾多的路徑和模式。然而，在長距離光纜(超過3000m)傳輸時，多個路徑

29、的光波會在接收端造成信號扭曲、失真，并導(dǎo)致傳輸數(shù)據(jù)的不清晰和不完整。Unit8【中譯英】(1) 數(shù)字同步系列：SDH (Synchronous Digital Hierarchy) (2)光纖通信網(wǎng)絡(luò)：optical telecommunication network(3) 同步復(fù)用器：synchronous multiplexers (4)網(wǎng)絡(luò)節(jié)點接口：Network Node Interface (NNI)(5) 線路終端復(fù)用器：Line Terminal Multiplexer (LTM) (6)分插復(fù)用器：Add-drop Multiplexer (ADM)【縮寫翻譯】SDH：Sync

30、hronous Digital Hierarchy 數(shù)字同步系列 | LTM：Line Terminal Multiplexer 線路終端復(fù)用器ADM：Add-drop Multiplexer 分插復(fù)用器【句子翻譯（英譯中）】(1) It brings out a revolution in telecommunications transmission system.它是電信傳輸體制的一次革命。 (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.他們的目標(biāo)是為同步傳輸系統(tǒng)制定一個世界通用的標(biāo)準(zhǔn)，以期向網(wǎng)絡(luò)運營者提供更具靈活性和經(jīng)濟性的網(wǎng)絡(luò)。 (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).除定義了NNI有關(guān)的標(biāo)準(zhǔn)外，CCITT還著手制定了決定著同步復(fù)用設(shè)備的運行(G.781,G.782 和 G.783)以及SDH網(wǎng)絡(luò)管理（G.784）的一系列標(biāo)準(zhǔn)。(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標(biāo)準(zhǔn)的基礎(chǔ)是直接同步復(fù)用，這是低價高效和靈活組網(wǎng)的關(guān)鍵。 (5) A

33、pproximately 5% of the SDH signal structure is allocated to supporting advanced network management procedures and practices.SDH信號結(jié)構(gòu)中有近5%被用于支持先進(jìn)的網(wǎng)絡(luò)管理程序和操作規(guī)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.線路終端復(fù)用器（LTM）：LTM可接受一批支路信號并將它們復(fù)用至適當(dāng)?shù)腟DH速率的光載體上，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.分插復(fù)用器（ADM）：一種特殊類型的終端復(fù)用單元，它是以“貫通”模式運行的。 (8) Almost all new fiber-transmission system

35、s now being installed in public networks use SDH or SONET.目前幾乎所有應(yīng)用在公眾網(wǎng)上的新的光纖傳輸系統(tǒng)都使用了數(shù)字同步系列或同步光纖網(wǎng)。Unit9【中譯英】 1光纖到家： Fiber To The Home (FTTH)2可靠的語音服務(wù)和高質(zhì)量的視頻服務(wù)：dependable voice and high-quality video service. 3光電轉(zhuǎn)換器：Electrical Converter (OEC) 4雙絞線：Twisted pair5電影品質(zhì)的視頻會議和電視電話：picture-quality videoconfer

36、encing, and videophones6用戶數(shù)字線路：Digital Subscriber Line (DSL)7互動式電視：interactive television 8高速互聯(lián)網(wǎng)接入：high-speed Internet access9互動雙向視頻服務(wù)：interactive two-way video-based services 10直播衛(wèi)星電視Direct Broadcast Satellite (DBS) television【英譯中】1High-speed data service:高速數(shù)據(jù)傳輸服務(wù) 2Signal fiber:單芯光纜3Broadcast cable

37、 television:直播有線電視4Coax and Hybird Fiber/Coax (HFC) networks：同軸電纜和混合光纖同軸網(wǎng)絡(luò)5Cable modems:電纜調(diào)制解調(diào)器6DC power network:直流電源網(wǎng)絡(luò).7Public Switched Telephone Network(PSTN): 公共交換電話網(wǎng)8Standard user interfaces:標(biāo)準(zhǔn)用戶接口【縮寫翻譯】 FTTH：Fiber to the Home 光纖到家 WDM：Wavelength Division Multiplexing 波分復(fù)用器【句子翻譯】（書P43，有點多）Unit10

38、【中譯英】(1)全球通信骨干網(wǎng)：The global telecommunications and networking backbone(2)波分復(fù)用：Wavelength Division Multiplexing(3)光脈沖：Pulses of light on fiber(4) 調(diào)頻無線信道：FM radio channels(5) 多?；儯簃ultimode distortion.(6) 單模玻璃光纖：single-mode glass fiber【句子翻譯（英譯中）】(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.一個主要的原因是一臺從電信號到光信號的單項轉(zhuǎn)換器只利用很少的光譜就可以把可達(dá)到的帶寬限制到大約每秒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，直徑為250微米的單股光線的信息載量可在10至80Gpbs之間,. (3) . while repeaters on a fiber-optic cable can be spaced up to 30 km.光纜上的中繼器（轉(zhuǎn)發(fā)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.這些光纖通常由塑料做成，可由便宜的發(fā)光二極管驅(qū)動；而長距離的鏈接使用更為昂貴的單模玻璃光纖，由激光驅(qū)動。Unit23【中譯英】(1) 局域網(wǎng)協(xié)議：Local Area Networks Protocols (2)令牌總線：Token Bus (3)以太網(wǎng)：Ethernet(4)沖突：Collision (5)令牌環(huán)：Token ring【縮寫翻譯】 LAN:Local Area Networks 局域網(wǎng) LLC: Logical link Control 邏輯鏈路控制層 MAC: Media Access Control 媒

42、體訪問控制層 FDDI: Fiber distributed data interface 光纖分布式數(shù)據(jù)接口【句子翻譯（英譯中）】(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.雖然802.3被廣泛應(yīng)用于辦公室，但在802標(biāo)準(zhǔn)發(fā)展期間，來

43、自通用汽車和其他公司的對工廠自動化感興趣的人們嚴(yán)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.換句話說，它容易計算一個設(shè)備在有機會傳送數(shù)據(jù)之前所經(jīng)過的最大限度的時間。Unit24 TCP/IP：Transmission Control Protocol/Internet Protocol 因特網(wǎng)協(xié)議（傳輸控制協(xié)議/網(wǎng)際協(xié)議）【句子翻譯（英譯中）】(1) The Inter

44、net is closely tied with a communications protocol system called TCP/IP, which stands for Transmission Control Protocol/Internet Protocol.因特網(wǎng)與TCP/IP通信協(xié)議組密切相關(guān)，TCP/IP指的是傳輸控制協(xié)議/網(wǎng)際協(xié)議。 (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.互聯(lián)層的目的是由互聯(lián)網(wǎng)絡(luò)上任意網(wǎng)絡(luò)發(fā)出源數(shù)據(jù)包并將它們送至信宿，而與到信宿所走的路由和網(wǎng)絡(luò)無關(guān)。 (3) In contrast, networks typically arent built with the OSI protocols, although the OSI model is used as a guide.與之相反，盡管OSI模型是一個典范，但以O(shè)SI協(xié)議所建設(shè)的網(wǎng)絡(luò)卻不典范。Unit25 WAP：Wireless

46、Application Protocol 無線應(yīng)用協(xié)議【句子翻譯（英譯中）】(1) WAP, short for Wireless Application Protocol, is a series of standard combinations similar to Internet application in developing mobile network.WAP是無線應(yīng)用協(xié)議的簡稱，它是開發(fā)移動網(wǎng)絡(luò)上類似互聯(lián)網(wǎng)應(yīng)用的一系列規(guī)范的組合。 (2) .but its specifical for the optimization of small screen, narrowband

47、users of devices(such as mobile phones).但專為小屏幕、窄帶的用戶裝置（如移動電話）進(jìn)行優(yōu)化。 (3) The past few years have witnessed a radical shift in the way we work, play, and communication.過去幾年已表明，我們工作、消遣和通信的方式已發(fā)生了根本改變。 (4) At the same time, people around the world have jumped to wireless communications at a frenzied pace.

48、同時，全世界的人們轉(zhuǎn)向到對無線通信瘋狂的地步。 (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，與移動環(huán)境相適應(yīng)的服務(wù)可以將新聞、股票等關(guān)鍵信息異步推送給用戶。 (6) A failure to do so could eventually translate into the loss of a significant percent

49、age or available traffic. 不這樣做的話，最終可能會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，移動互聯(lián)網(wǎng)的開發(fā)（WAP使之能實現(xiàn)）給新用戶創(chuàng)造各種機會，提供更加個性化的服務(wù)和銷售心的應(yīng)用程序。 附錄1：第一單元課文翻譯通信是人類固有需求

50、的一部分，人類一開始就使用不同的技術(shù)和方式進(jìn)行交流，而環(huán)境 和可利用的技術(shù)也限定了人類通信的方法和方式。數(shù)據(jù)通信涉及到在通信雙方傳遞信息.現(xiàn)在我們共同來學(xué)習(xí)關(guān)于數(shù)據(jù)通信的基本知識.l 信號1信號和0信號不能這樣通過網(wǎng)絡(luò)鏈路傳送。它們必須進(jìn)一步被轉(zhuǎn)換成傳輸介質(zhì)能夠接受的形式。傳輸介質(zhì)通過沿著一條物理線路傳輸能量來工作。所以，一個1信號和0信號的數(shù)據(jù)流必須被轉(zhuǎn)換為電磁信號形式的能量。l 模擬和數(shù)字?jǐn)?shù)據(jù)和代表它們的信號都能夠采用模擬的或者數(shù)字的形式。模擬涉及連續(xù)的某些事物一一一組特殊點的數(shù)據(jù)以及各點之間所有可能的點。數(shù)字涉及離散的某些事物。信息能夠是模擬的或數(shù)字的。模擬信息是連續(xù)的。數(shù)字信息是離散的。信號可以是模擬的或數(shù)字的。模擬信號在一個范圍內(nèi)可以有任何值：而數(shù)字信號僅有有限數(shù)量的值。l 信道的特性首先是傳輸率。一個信道的傳輸率是由它的帶寬和速度決定的。帶寬是一個通道能夠支持的頻率范圍。因為傳輸?shù)臄?shù)據(jù)能被分配到不同頻率，所以帶寬越寬頻率越多，同一時間能被傳輸?shù)臄?shù)據(jù)就越多。傳輸數(shù)據(jù)的速度通常以每秒多少比特或以波特率來表示。每秒比特(bps)是在一秒內(nèi)能被傳輸?shù)谋忍財?shù)。波特率是被傳輸?shù)男盘柮棵胱兓拇螖?shù)。一般地，僅當(dāng)1比特以一個信號變化被傳輸時，每秒比特和波特率才是相同的。第二是傳輸方向。數(shù)據(jù)傳輸方向被分為單