Microwave communication uses high-frequency(56)waves that travel in straightlines through the air. Because the waves cannot(57)with the curvature of the earth, they can be(58)only over short distance. Thus, microwave is a good(59)for sending data between

题目

Microwave communication uses high-frequency(56)waves that travel in straightlines through the air. Because the waves cannot(57)with the curvature of the earth, they can be(58)only over short distance. Thus, microwave is a good(59)for sending data between buildings in a city or on a large college campus. For longer distances, the waves must be relayed by means of "dishes" or(60).These can be installed on towers, high buildings, and mountain tops.

A．optical

B．radio

C．electrical

D．magnetic

相似考题

1.Communication through writing emancipates man from the constraints imposed by the face－to－face distance and the () of time.A、spontaneityB、responsibilityC、complexityD、confusion

2.【An overall cellular network contains a number of different elements from the base transceiver station (BTS) itself with its antenna back through a base station controller (BSC), and a mobile switching centre (MSC) to the location registers (HLR and VLR) and the link to the public switched telephone network (PSTN). Of the units within the cellular network, the BTS provides the direct communication with the mobile phones. There may be a small number of base stations then linked to a base station controller. This unit acts as a small centre to route calls to the required base station, and it also makes some decisions about which of the base station is best suited to a particular call. The links between the BTS and the BSC may use either land lines of even microwave links. Often the BTS antenna towers also support a small microwave dish antenna used for the link to the BSC. The BSC is often co-located with a BTS. The BSC interfaces with the mobile switching centre. This makes more widespread choices about the routing of calls and interfaces to the land line based PSTN as well as the HLR and VLR.】 From the paragraph above, in a cellular network, the （98） can provide direct communication with a mobile phone, the （99） acts as a small centre to route calls to the required base station, and it also makes some decisions about which of the base station is best suited to a particular call.（100） can be used to link the BSC with related BTS。A. BSC B. BTS C. MSC D. VLR A. BSC B. BTS C. MSC D. HLR A. Land lines B. Microwave links C. Microwave dish antenna D. Land lines or microwave links

3.Wireless telecommunications networks are generally implemented and administered using（）communication.This implementation takes place at the （）level of OSI model network structure.A．microwave B．radio C．FM D．AMA．physical B．link C．network D．transport

4.根据下面的文字资料回答 71～75 题In the following essay，each blank has fourchoices．Choose the best answer and write down on thean，swer sheet．Microwave communication uses（ 1 ）frequency radio waves that travel instraighdine sthroughthe air．Because the waves cannot（ 2 ）with the curvature of the earth，they can be （ 3 ）onlyover short distance．Thus，microwave is a good（ 4 ）for sending data between bulldingsin a city or on a large college campus．For longer distances，the waves must berelayed by means of“dishes”or（ 5 ）．These can be installed on towers，highbuildings，and mountain tops．第71题：文中（ 1 ）处正确的答案是（ ）。A．highB．10wC．1ongD．short

更多“Microwave communication uses high－frequency(56)waves that travel in straightlines through ”相关问题

  • 第1题：

    Communication through writing emancipates man from the constraints imposed by the face-to-face___and the spontaneity of time.

    A. confusion

    B. responsibility

    C. complexity

    D. distance


    参考答案D

  • 第2题：

    Which two statements about Oracle Direct Network File System (NFS) are true?()

    A. It bypasses the OS file system cache.

    B. A separate NFS interface is required for use across Linux, UNIX, and Windows platforms.

    C. It uses the operating system kernel NFS layer for user tasks and network communication modules.

    D. File systems need not be mounted by the kernel NFS system when being served through Direct NFS.

    E. Oracle Disk Manager can manage NFS on its own, without using the operating system kernel NFS driver.


    参考答案：A, E

  • 第3题：

    Most IP layer-based proxy mechanisms，such as network address translation (NAT)，only supportuni-directional proxy，from the internal network to external network(the Interned．The proxvestablishes the communication channel by (71) IP addresses．The IP addresses must be (72) ．These proxy mechanisms prevent applications that must establish return data channels from establishing their data channels，such as，multimedia applications．IP layer-based proxy mechanisms need additional software (73) for each application that uses (74) channels． SOCKS identifies communication targets through domain names，overcoming the restriction of Usina private IP addresses．SOCKS can use domain names to establish communication between separate LANs，with (75) IP addresses．

    (66)

    A．manufacturing

    B．manipulating

    C．conduct

    D．implement


    正确答案：B

  • 第4题：

    ● When a large packet wants to travel through a network whose MTU is too small, one solution is to allow routers to break up the packet into （）. （）A. messages B. frames C. fragments D. bits


    正确答案：C
    当一个很大的数据包要通过网络传输时，但链路层的MTU，很小，将采用一种方法是这些数据包分片。MTU是Maximum Transmission Unit的缩写。意思是网络上传送的最大数据包。MTU的单位是字节。
    　　大部分网络设备的MTU都是1500。如果本机的MTU比网关的MTU大，大的数据包就会被拆开来传送，这样会产生很多数据包碎片，增加丢包率，降低网络速度。把本机的MTU设成比网关的MTU小或相同，就可以减少丢包。

  • 第5题：

    What kind of pressure systems travel in easterly waves ________．

    A.High pressure

    B.Low pressure

    C.Subsurface pressure

    D.Terrastatic pressure


    正确答案：B

  • 第6题：

    Which of the following communication methods will provide the maximum bandwidth for video streaming through a media extender？（）

    • A、100BaseT Ethernet
    • B、802.11g
    • C、Z-Wave
    • D、Bluetooth

    正确答案:A

  • 第7题：

    多选题
    Which two statements about Oracle Direct Network File System (NFS) are true?（）
    A

    It bypasses the OS file system cache.

    B

    A separate NFS interface is required for use across Linux, UNIX, and Windows platforms.

    C

    It uses the operating system kernel NFS layer for user tasks and network communication modules.

    D

    File systems need not be mounted by the kernel NFS system when being served through Direct NFS.

    E

    Oracle Disk Manager can manage NFS on its own, without using the operating system kernel NFS driver.


    正确答案： E,A
    解析： 暂无解析

  • 第8题：

    单选题
    According to the passage, why are people more likely to tell the truth through certain mesa of communication?
    A

    They are afraid of leaving behind traces of their lies.

    B

    They believe that honesty is the best policy.

    C

    They tend to be relaxed when using those mesa.

    D

    They almost practiced at those forms of communication


    正确答案： D
    解析：
    细节题。根据第四段前两句，如果对一个人的交流内容进行记录，而且日后可以拿来与之对证的话，他就比较倾向于讲真话。A项“leaving behind traces of their lies”指文中的“conversation is being recorded and could be reread”，故选A。

  • 第9题：

    单选题
    Which statement is correct regarding NBAR and NetFlow？（）
    A

    NetFlow uses five key fields for the flow

    B

    NBAR examines data in Layers 3 and 4

    C

    NetFlow examines data in Layers 3 and 4

    D

    NBAR examines data in Layers 2 through 4

    E

    NetFlow examines data in Layers 2 through 4


    正确答案： E
    解析： 暂无解析

  • 第10题：

    单选题
    Wlse uses snmp communication with an ethernet switch for what purpose？（）
    A

    shut down rogue access points

    B

    configure access points

    C

    discover access points

    D

    inventory access points


    正确答案： A
    解析： 暂无解析

  • 第11题：

    多选题
    What are two examples of RE exception traffic?（）
    A

    BGP updates that travel through the local router and are destined for a remote router.

    B

    OSPF hello packets that are sent from a remote router and are destined for the local router.

    C

    Telnet traffic that is sent from a remote host and is destined for the local router.

    D

    Telnet traffic that travels through the local router and is destined for a remote end host.


    正确答案： D,C
    解析： 暂无解析

  • 第12题：

    单选题
    What kind of pressure systems travel in easterly waves（）.
    A

    High pressure

    B

    Low pressure

    C

    Subsurface pressure

    D

    Terrastatic pressure


    正确答案： A
    解析： 暂无解析

  • 第13题：

    microwave sterilization


    正确答案：microwave sterilization：微波灭菌法是用微波(频率在300兆赫到300千兆赫之间的高频电磁波)照射而产生的热量杀灭微生物的方法。
    microwavesterilization：微波灭菌法,是用微波(频率在300兆赫到300千兆赫之间的高频电磁波)照射而产生的热量杀灭微生物的方法。

  • 第14题：

    In the following essay, each blank has four choices. Choose the best answer and write-down on the answer sheet.

    Microwave communication uses high-frequency(71)waves that travel in straightlines through the air. Because the waves cannot(72)with the curvature of the earth, they can be(73)only over short distance. Thus, microwave is a good(74)for sending data between buildings in a city or on a large college campus. For longer distances, the waves must be relayed by means of "dishes" or(75). These can be installed on towers, highbuildings, and mountain tops.

    A．optical

    B．radio

    C．electrical

    D．magnetic


    正确答案：B

  • 第15题：

    In 8011 terminology．all communication was to go through the base station, called an(75)

    A．Access Channel

    B．Access System

    C．Access Point

    D．Network Access Point


    正确答案：C
    解析：在802.11的术语中，所有的通信都经过一个被称作AP(访问点)的基站。

  • 第16题：

    （75） ● means the conducting of business communication and transaction over network and through computers.

    （75）

    A. E-Mail

    B. E-Government

    C. E-text

    D. E-Commerce


    正确答案：D
    答案分析：试题（75）分析
    参考译文
        电子商务就是通过计算机在网上进行商务通信和交易。
    参考答案
          （75）D

  • 第17题：

    work performance information is circulated through（）processes.

    A.planning
    B.change
    C.improvement
    D.communication

    答案：D
    解析：
    翻译：工作绩效信息通过（）流程传播。
    A.规划
    B.变更
    C.改进
    D.沟通
    工作绩效信息通过沟通过程进行传递。

  • 第18题：

    单选题
    An electronic depth finder operates on the principle that（）.
    A

    radio signals reflect from a solid surface

    B

    sound waves travel at a constant speed through water

    C

    radar signals travel at a constant speed through water

    D

    pressure increases with depth


    正确答案： D
    解析： 暂无解析

  • 第19题：

    单选题
    Barely able to speak because of the cold, the communication among the two explorers had to be done through gestures.
    A

    the communication among the two explorers had to be done through gestures

    B

    the communication between the two explorers had to be done through gestures

    C

    the two explorers had to communicate through gestures

    D

    the two explorers had to communicate between themselves from gestures

    E

    gestures were used to communicate between the two explorers


    正确答案： E
    解析：
    原句修饰词组的位置不正确，C纠正了这个错误。

  • 第20题：

    单选题
    During steering gear test should be moved through its full travel in both directions（）
    A

    pump

    B

    the cylinder

    C

    the hunting gear

    D

    the rudder


    正确答案： D
    解析： 暂无解析

  • 第21题：

    单选题
    In the COSPAS-SARSAT system distress signals are processed by（）and the resulting data are forwarded to（）through（）communication network.
    A

    MCC/LUT/RCC

    B

    LUT/MCC/RCC

    C

    LUT/RCC/MCC

    D

    LUT/RCC/LUT


    正确答案： B
    解析： 暂无解析

  • 第22题：

    名词解释题
    高频噪声high-frequency noise

    正确答案： 主要噪声成分的频率高于1000Hz的噪声。
    解析： 暂无解析

  • 第23题：

    单选题
    The car will be guided by a differential GPS system that corrects errors arising in global positioning satellite signals（）they travel through the ionosphere and troposphere.
    A

    as

    B

    that

    C

    what

    D

    where


    正确答案： C
    解析： 暂无解析

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