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1、2022年考博英语-西南政法大学考试题库及模拟押密卷（含答案解析）1. 单选题If you want to see the future of broadband communications, look to the stars. The heavens could soon be filled with more than 400 satellites providing internet users with low cost, direct-to-the-home connections that are hundreds of times faster than todays dia
2、l-up modems. With unobstructed views of virtually the entire world, satellites are poised to deliver interactive broadband services in ways even advanced ground-based networks will be hard-pressed to match.The new breed of satellites will act as powerful signal repeaters in the sky, receiving and re
3、sending radio transmissions from ground-based antennas. Costing far less per unit capacity than most satellites now in service, they will employ new digital technologies that will improve the capacity, reliability and security of data communications. Moreover, because the systems will operate at ext
4、remely high radio frequencies, they will use narrow radio beams capable of communicating with ultra small antennas that can be easily mounted on most homes.Two types of satellite systems have been proposed. Geostationary satellites will orbit 36, 000 kilometers 22, 000 miles above the equator at the
5、 same speed as the earths rotation and thus appear from the ground to be stationary. They will communicate with fixed orientation dish antennas attached to customers homes and use advanced signal processing to compensate for transmission delays caused by the great distances their radio signals must
6、travel. Lowearth orbit (LEO) satellites, in contrast, will circle the globe once every two hours at altitudes under 1,500 kilometers, reducing the time needed to beam signals to and from the earths surface. But they will require sophisticated subscriber antennas able to track and communicate with th
7、e fast-moving LEO satellites.Both types of satellites will avoid many of the complications that plague ground-based networks. Specific advantages include the following.The dirty little secret of broadband is that the technical limitations of ground based networks will severely restrict availability.
8、 Digital subscriber line (DSL) signals decay on long telephone lines or on those of poor quality. Local multipoint distribution service (LMDS) signals cannot penetrate leafy trees, buildings or other obstructions. Cable performance deteriorates if too many households in a neighborhood log on at the
9、same time. Fiber-to-the-home is so costly as a retrofit that is usually considered economically viable only for new housing construction. For up to one third of the population in the U. S. and an even greater portion worldwide, satellite technology will not simply be a choice, it will be the choice.
10、1.Which of the following is not true according to the passage?2.All of the following is mentioned as the new type of satellites is described EXCEPT（ ）.3.Why does a geostationary satellite appear to be immobile?4.What advantage does the last paragraph intend to focus on?问题1选项A.Satellites will make th
11、e access to the Internet cheaper and more convenient.B.Satellites cost less than todays dial-up modems.C.Satellites will be superior to ground-based networks to deliver interactive broad-band services.D.Ground-based antennas can send radio transmissions.问题2选项A.narrow radio beams will be usedB.new di
12、gital technologies will be takenC.the systems of them will work at extremely high radio frequencies.D.their signals can be easily mounted on most homes.问题3选项A.Because it is fixed all the time.B.Because its orbit speed is the same as the earths rotation.C.Because its position is above the equator.D.B
13、ecause it can communicate with fixed-orientation dish antennas.问题4选项A.Satellites can improve the availability of the Internet.B.To transmit the DSL signals without delay.C.Their signals can penetrate obstructions.D.Low cost【答案】第1题:B第2题:D第3题:B第4题:A【解析】1.细节事实题。根据第一段第二句“providing internet users with lo
14、w cost”可知选项A正确；根据第一段最后一句“.satellites are poised to deliver interactive broadband services in ways even advanced ground-based networks will be hard-pressed to match.卫星静止不动的以先进的地面网络也难以匹敌的方式提供交互式宽带服务。”选项C符合原文。根据第二段第一句“receiving and resending radio transmissions from ground-based antennas.接收和重新发送来自地面天线的
15、无线电传输。”选项D符合原文。只有选项B在文中没有提及，所以不正确。2.细节事实题。根据第二段倒数第二句“they will employ new digital technologies.”可知选项B正确；以及最后一句“the systems will operate at extremely high radio frequencies, they will use narrow radio beams capable of communicating with ultra small antennas that can be easily mounted on most homes. 该
16、系统将在极高的无线电频率下运行，它们将使用能够与超小型天线通信的窄无线电波束，这种天线可以很容易地安装在大多数家庭中。”选项A和C符合原文；选项D中的“signals”与原文中的“antennas”不符，所以不正确。3.细节事实题。根据关键词“geostationary satellite”定位到第三段第二句“Geostationary satellites will orbit 36, 000 kilometers 22, 000 miles above the equator at the same speed as the earths rotation and thus appear from the ground to be stationary. 地球同步卫星将以与地球自转相同的速
