Chapter 10: Wireless Communications Key
1. The VLF and MF bands are both frequency bands within the radio spectrum.
2. The EHF band is comprised of lower frequency radio waves compared to the VLF band.
3. AM and FM are analog broadcasting technologies whereas DAB and DVB are digital.
4. AM and FM radio broadcasting offer better audio quality compared to DAB.
5. DAB is a digital broadcasting technology.
6. DAB offers near CD-quality audio broadcasting.
7. Satellite radio is a technology that offers radio broadcasting over a wider coverage area compared to AM and
FM radio broadcasting.
8. The radio spectrum’s VHF and UHF bands are used for TV broadcasting, among other applications.
9. DTV is a digital television broadcasting technology.
10. Bluetooth is a technology that employs radio waves and provides short distance communication between
devices such as computers and other related devices.
11. The communication between a base station within a cellular telephone network and a cellular phone is
implemented via radio waves.
12. Satellite telephones communicate directly with satellites.
13. One example of a remote sensing technique that employs radio waves is RADAR.
14. RADAR is based on emitting radio waves by a source towards an object and analyzing the waves reflected
by the object.
15. Passive RFID tags can emit radio waves through their antenna using energy from the battery when prompted
by the tag reader.
16. The main advantage of RFID tags compared to bar codes is that they can be read remotely, without
requiring a direct line of site between the tag and the reader.
17. Amateur radio is also called ham radio.
18. Wi-fi is a technology that utilizes radio waves with frequencies of 10 GHz.
19. FM radio broadcasting utilizes the 535 kHz-1605 kHz frequency range of the electromagnetic spectrum.
20. The first satellite successfully launched into space was called INMARSAT.
22. An antenna’s size depends on the area of coverage as well as the wavelength of the electromagnetic wave
used for communications.
23. Solar panels are comprised of transducers that are used to convert electricity into light.
24. The term uplink used within the context of satellite technology refers to the transmission of radio waves
from the satellite to an earth station.
25. Satellites occasionally drift from their designated orbits and have to be repositioned back to their orbit
through command signals issued by ground stations.
26. A MEO satellite resides at a higher altitude compared to a GEO satellite.
27. A GEO satellite has a greater area of coverage compared to a LEO satellite.
28. Absorption and scattering are two effects that act to attenuate radio waves as they travel through the
atmosphere.
29. GPS is based on a concept called triangulation.
30. GPS satellites are equipped with quartz clocks whereas GPS receivers are equipped with atomic clocks.
31. A satmodem is a piece of equipment used to achieve satellite Internet connectivity.
32. An approach called wide area augmentation system (WAAS) is used to provide better precision to aircraft
and civilian users compared to GPS.
33. Which of the following are bands found within the radio spectrum?
34. Which of the following audio broadcasting technologies offer near-CD quality audio?
35. Which of the following is a technology that offers very high fidelity television broadcasting?
36. Which of the following offers more TV channels to users?
37. Which of the following satellite systems is specifically designed to support maritime communications?
38. Which of the following technologies is considered an alternative to DSL and cable modems for providing
metropolitan wireless connectivity between users and Internet service providers?
39. Which of the following is the name of the robots used by NASA’s recent exploration of Mars?
40. Which of the following is a remote sensing technique that employs radio waves?
41. Which of the following are types of RFID tags?
42. Which of the following types of RFID tags emit radio waves through their antenna using energy from the
battery when prompted by the tag reader?
43. Which of the following is a frequency employed by Wi-Fi?
44. Which of the following is an alternative name for amateur radio?
45. Which of the following is/are component(s) of a satellite?
46. Which of the following satellite components is responsible for converting light into electricity?
47. Which of the following are types of satellite antennae?
48. Which of the following terms denotes the communications taking place from the satellite to the earth
station?
49. Which of the following effects may cause a satellite to shift from its designated orbit?
50. Which of the following are possible orbital shapes?
51. Which of the following are types of satellite orbits?
52. Which of the following orbits is closest to the surface of the earth?
53. A satellite in which orbit would be associated with the highest latency?
54. A satellite in which orbit would complete a single revolution around the earth in 24 hours?
55. A satellite in which orbit would complete one revolution around the earth the fastest?
56. What is the approximate orbital altitude of GEO satellites?
57. What is the speed of electromagnetic waves within a vacuum?
58. How much time would it take for a radio wave signal to be transmitted from one satellite to another satellite
if the two satellites were spaced at a distance of 100 km?
59. Which of the following are effects that act upon a radio wave as it travels through the atmosphere?
60. At least how many satellite measurements are needed by a GPS receiver for triangulating its position?
61. Which of the following is a piece of equipment used for satellite Internet connectivity?
62. Ever since ____________________ first demonstrated how to communicate using long-distance radio
waves, people have used them for information exchange.
63. The ____________________ that radio waves provide, combined with the long distances they can travel
and their capacity for carrying large amounts of information, make them indispensable to most information
applications.
64. Analog radio is vulnerable to unwanted effects such as ____________________ from other sources, which
cannot be removed effectively.
65. Because terrestrial radio broadcasting has a limited reach, ____________________ radio has become an
attractive alternative.
66. The electromagnetic spectrum’s ____________________ and ____________________ bands are
designated for TV broadcasting, among many other applications.
67. Confining radio waves within a coaxial cable enables better picture and sound quality by reducing
____________________ and provides hundreds of channels to the consumer.
68. Numerous maritime satellite systems such as____________________ are specifically designed to provide
maritime communications.
69. One popular wireless networking technology is ____________________ which uses radio waves at
frequencies of 2.4 GHz and 5 GHz.
70. ____________________ is considered an alternative to DSL and cable modems for providing metropolitan
wireless connectivity between users and Internet service providers.
71. ____________________ is a technology used to provide wireless connectivity between mobile telephones
and their earpieces, which gives users hands-free access to mobile phones.
72. Satellite telephones communicate directly with ____________________, unlike cellular telephones, which
communicate directly with terrestrial base stations.
73. ____________________ telephones are useful in places where no landline phones or base stations are
available, such as in mountainous or desert regions.
74. The ____________________ system uses a combination of numerous satellites, receivers, and ground
stations to give positional information in three dimensions.
75. NASA’s recent exploration of Mars used robots called rovers to analyze the planet’s surface and send the
information to the antennas of the ____________________ network on Earth.
76. ____________________ radar is primarily used to map the surface of the Earth; it is also used for
geographical applications that involve large stationary objects.
77. ____________________ is an innovative approach for identifying and tracking shipping containers, pets,
and sometimes even people.
78. RFID tags are classified as either ____________________ or ____________________.
active, passive or
79. ____________________ tags have a longer range than their passive counterparts and can store and transmit
a greater amount of information.
80. In many applications, RFID tags compete with another type of tag called a ____________________.
81. Although RFID technology is increasing in popularity for many applications, the lower
____________________ of bar code systems and their wide deployment in existing applications will probably
make them the preferred choice for the near future for numerous applications.
82. Stores can install special equipment called ________________________________________ for
communicating directly with credit card companies and banks via satellites.
83. Beginning with the launch of Sputnik in ____________________ the space race between the former Soviet
Union and the United States spurred rapid advances in satellite technology and significant developments in
space travel and exploration.
84. An antenna’s size depends on the area of coverage as well as the ____________________ of the
electromagnetic wave used for communications.
85. When the satellite is in the path of the sun’s rays, its ____________________ receive solar energy and
convert them into electricity.
86. The communications system, sometimes called the _________________________ of a satellite consists of
various modulators and demodulators, transponders, encoders and decoders, multiplexers and demultiplexers,
amplifiers, and other circuits.
87. The ____________________ system on the satellite constantly communicates with the control station to
keep the satellite in good working condition.
88. A ____________________ satellite is positioned approximately hundreds of kilometers to a few thousand
kilometers above the Earth’s surface, and completes one revolution within its orbit about once every few hours
or so, depending on altitude.
89. Because a satellite’s maximum field of view, or area of coverage, is a function of its
____________________ LEO satellites tend to cover only a small portion of the Earth’s surface.
90. Interestingly, not all radio wavelengths encounter the same effects in the atmosphere. Some
____________________ are more susceptible to its detrimental effects than others.
91. The GPS is a network of about ____________________ MEO satellites and numerous earth stations that
constantly monitor these satellites.
92. The basis of GPS is called ____________________.
93. GPS was initially intended for military applications, but later became available to civilians. The system is
currently controlled by the ____________________ in the United States.
94. In theory, the distance between the GPS receiver and at least ____________________ satellites must be
known by the GPS receiver.
95. A recent approach called ____________________ is used to provide better precision to aircraft and civilian
users compared to traditional GPS. It employs a combination of ground-based stations and satellites rotating
96. List the various applications of radio waves.
97. List the main components of a satellite.
98. List the main satellite orbits in order of increasing altitude.
99. Discuss the various effects of the atmospheric channel on radio waves.
100. Discuss the difference between GPS and DGPS.