通信英语训练试题测试题综合测试二

1、PAGE PAGE 9模拟试卷一 分值题号 TOTAL SCORE单项选择题（每题只有一个正确答案，每题1分，共10分）1. The switch, circuit switches, have no capability of _ users data on their way to the destination. A. calling, stored B. called, storing C. to call, to store D. be called, be stored2. The switching element is a computer a message processo

2、r, with processing and storage capabilities. Message travels independently and asynchronously, their own way from source to destination. A. be referred to as; finding B. referred to as, finding C. be referred to as, to find D. referred to, finding3. The telephone contains a transmitter and receiver

3、for_ back and forth analog voice and analog electrical signals. A. convert, in B. converting, between C. conversion, to D. converted, into4. The trunks are designed multiple voice-frequency circuits either FDM or synchronous TDM. A. carry, use B. carried, used C. to carry, to use D. to carry, using5

4、. Designers have found it convenient these nodes into a hierarchy or tree topology, five classes of switching centers or nodes. A. organization, consist B. organize, consisting C. to organize, consisting of D. organizing, to consist6. The term ISDN was first defined within the CCITT in 1972. It refe

5、rred to a network end-to-end digital connectivity _a range of services.A. providing, for B. provision, to C. provided, with D. provide, into7. In fact, ISDN conceived a quarter of a century ago and is only now to reach maturity. A. is, begin B. was, beginning C. be, to begin D. will be, began8. As r

6、egards economy, early studies suggested that digital services _significant advantages since a substantial quantity of interface equipment in the telephone exchange could . A. offered, be eliminated B. offer, eliminate C. offers, is eliminated D. to offer, to eliminate9. The enhanced quality is achie

7、ved when a signal is digitally encoded degradation the transmission medium. A. overcome, to B. overcame, with C. overcoming, over D. to overcome, due to10. Similarly, the introduction of voice encoding techniques_ pulse code modulation contributed the ISDNs concept evolution. A. usage, on B. using,

8、to C. use, with D. used, so as to二、英译汉短语（每题1分，共15分）1. the capability of storing or manipulating users data 2. the information regarding the source and destination addresses 3. the overall transmission delay of the message 4. packet switching 5. transmission unit 6. low channel utilization 7. the swi

9、tching nodes called tandem switches 8. architectural components 9. full duplex 10. multiple voice-frequency circuits 11. isolated subnetworks 12. two subscribers attached to different end offices 13. degradation due to the transmission medium 14. digital communication 15.public communication carrier

10、s 16. bandwidth limitations 17.basic access signaling rate 三、汉译英短语（每题1分，共15分）1、电路交换 .2、双绞线 3、存储转发方式 4、交换技术 5、信息转换 6、公众电信网 7、本地环路 8、收费中心 9、中间交换节点 10、拓扑 11、灵活性 12、综合业务数字网 13、接口设备 14、语音编码 15、基本接入 四、阅读理解（每题2分，共20分），根据文章内容判断（）（X）PASSAGE ONEBy far the largest circuit-switched network is the public telecom

11、munications networkthe telephone network. This is actually a collection of national networks interconnected to form an international service. Although originally designed and implemented to service analog telephone subscribers, it handles substantial data traffic via modem, and is gradually being co

12、nverted to a digital network.The public telecommunication network, as with any communications network, can be described using four generic architectural components. Stations: generally denoted as subscribers, these are the devices that attach to the network. Interfaces: the interface between the sta

13、tions and the network, referred to in the phone system as the local loop. Nodes: the switching centers in the network. Links: the branches between nodes, referred to as trunks.Most of the subscribers on the network are telephones. The telephone contains a transmitter and receiver for converting back

14、 and forth between analog voice and analog electrical signals. With the introduction of the digital data system, some subscribers that transmit digital signals have been incorporated into the network.The local loop is a pair of wires, generally twisted pair, That connects a subscriber to one of the

15、nodes in the network. The local loop generally covers a distance of a few kilometers to a few tens of kilometers at most.1) The largest circuit-switched network is referred to as the public telecommunications network-the telephone network.( )2) The telephone network originally designed and implement

16、ed to serve a digital network. ( )3) We can describe the public telecommunications network with Stations, Nodes and Links. ( )4) The telephone only contains a receiver for converting back and forth between analog voice and anolog electrical signals. ( )5) The local loop is a pair of wires, generally

17、 twisted pair, that connects a subscriber to one of the nodes in the network . ( )6) The local loop generally covers a distance of a few meters to a few kilometers. ( )PASSAGE TWO The term ISDN was first defined within the CCITT in 1972. It referred to a network providing end-to-end digital connecti

18、vity for a range of services. It also used the idea of a totally open network with universally available and standardized “ports” that can plug in everywhere. The concept has since then evolved from the existing telephone networks of countries undergoing changes due to the introduction of totally ne

19、w digital technology in the switching and transmission equipment. Similarly, the introduction of voice encoding techniques using pulse code modulation contributed to the concepts evolution. Initially, voice encoding was based upon a 64 kbit/s transmission rate. Today two 64 kbit/s, or 2B-channels co

20、upled with a basic access signaling rate of 16 kbit/s, that is, the D-channel, constitute the essential ISDN transmission rate of 144 kbit/s. Currently PSTN, available in almost 200 countries and territories around the world, offers universal voice access to almost 750 million telephones around the

21、world. ISDN is the network which will progressively provide a similar universal access for not only voice but data, facsimile, video, text, and other services as well. In the industrialized countries, the evolutionary nature of the ISDN concept has been a matter of economic practicality considering

22、the vast telephone infrastructure already in place. The primary emphasis, however, has been the enhancement of the services rather than a single replacement of the services rather than a single replacement of existing equipment. This evolutionary approach has also merit for most of the developing co

23、untries, although in some instances where analog facilities do not exist presently or where they are very limited, the direct installation of digital facilities could allow a direct leapfrog to ISDN capabilities.Many planners believe that the transition form experimental ISDN technology to operation

24、al system will be convincingly made in the next few years. Certainly the 1990s will be the time of rapid operational growth. If true, a lot of issues will have to be resolved in coming months rather than in coming years . The current study period of the CCITT (19891992) will, of necessity, resolve v

25、irtually all standards issues on ISDN including even wideband ISDN for transmission rates up to 155 Mbit/s.ISDN is not a four-letter work. It is a blueprint to the electronic communications system of the future.7) The term ISDN was first defined with the CCITT in 1982. ( )8) ISDN referred to a netwo

26、rk providing end-to-end digital connectivity for a range of services. ( )9) Today two 64 kbit/s, or 2 B-channels coupled with a basic access signaling rate of 16 kbit/s, that is ,the D-channel, constitute the essential ISDN transmission rate of 144 kbit/s (2B+D).( )10) ISDN is the network which will

27、 progressively provide a similar universal access for only voice, facsimile and video. ( )11) ISDN is a blueprint to the electronic communications system of the future. ( )12) The author thinks that a lot of issues on ISDN will have to be resolved in a few months. ( )五、英译汉短文（每题10分，共40分）1. Each subsc

28、riber connects via local loop to a switching center, known as an end office. Typically, an end office will support many thousands of subscribers in a localized area. There are over 19,000 end offices in the United States, so it is clearly impractical for each end office to have a direct link to each

29、 end other office. Rather, intermediate switching nodes are used.2. By far the largest circuit-switched network is the public telecommunications networkthe telephone network. This is actually a collection of national networks interconnected to form an international service. Although originally designed and implemented to service analog telephone subscribers, it handles substantial data traffic via modem, and is gradually being converted to a digital network.3. The local loop is a pair of wires, generally twisted pair, that connects a subscriber to one of the nodes in the network. The