SNSU

Test Details :

Test Name CHAPTER 7: SATELLITE COMMUNICATIONS

Test Id 240407133500

Generate 2024-05-17 07:07:56 (IST)

Q1. There were many limitations that caused problems on the first communications satellites. Of the following
problems, which one was considered the most severe?

1. he excessive size

2. the excessive weight

3. the too low orbit altitude

4. the lack of a suitable power source

Right Answer : 4

Q2. The longitude is a:

1. horizontal line that runs from west to east

2. vertical line that runs from north to south

3. line parallel to the equator

4. line perpendicular to the equator

Right Answer : 4

Q3. A receiver for frequency-hopping spread-spectrum would be:

1. a narrowband receiver

2. a wideband receiver

3. a direct-conversion receiver

4. a CDMA receiver

Right Answer : 1

Q4. What is the purpose of a thermal control subsystem in a satellite?

1. it is for the optimization control of the antennas

2. it is for protection purposes such as the radiation from the sun

3. it is for the power supply of the satellite

4. it is for the temperature control inside the satellite

Right Answer : 4
Q5. What is super-synchronous orbit?

1. positioning of the satellite for optimum performance

2. the process of firing the rockets under ground control to maintain or adjust the orbit

3. is an orbit significantly above synchronous orbit, where spacecraft are intentionally placed at the end of their
operational life

4. the process of stopping the thruster of a satellite and letting it fall through the ground

Right Answer : 3

Q6. In satellite systems, a bent-pipe architecture:

1. have inter-satellite communication

2. have components and subsystem tasks modularized and divided into separate spacecraft

3. is the most commonly used satellite network architecture

4. all of these

Right Answer : 3

Q7. As the height of a satellite orbit gets lower, the speed of the satellite

1. increases

2. decreases

3. remains the same

4. none of the above

Right Answer : 1

Q8. In satellite history, the Echo:

1. accomplished the first transatlantic transmission using satellite

2. is the first artificial satellite used for relaying terrestrial communications

3. is the first transponder type satellite

4. is the first space craft to detect the Van Allen Radiation Belt

Right Answer : 1

Q9. Which of the following power sources is/are considered a practical choice for satellites?

1. solar cells only

2. storage batteries only

3. a combination of solar cells and storage batteries

4. sunlight and leclanche cells

Right Answer : 3
Q10. A receiver for direct-sequence spread-spectrum would be:

1. a narrowband receiver

2. a wideband receiver

3. a direct-conversion receiver

4. a "chip-rate" receiver

Right Answer : 2

Q11. Describe a hemispherical beam:

1. typically target up to 20% of the earth's surface

2. concentrate their power to very small geographical areas

3. radiation patterns of earth coverage antennas have a beamwidth of approximately 17°

4. all of these

Right Answer : 1

Q12. What is attitude control?

1. positioning of the satellite for optimum performance

2. the process of firing the rockets under ground control to maintain or adjust the orbit

3. is an orbit significantly above synchronous orbit, where spacecraft are intentionally placed at the end of their
operational life

4. the process of stopping the thruster of a satellite and letting it fall through the ground

Right Answer : 1

Q13. The main function of a communications satellite is as a(n):

1. repeater

2. reflector

3. beacon

4. observation platform

Right Answer : 1

Q14. What is Sputnik I?

1. the first active earth satellite

2. the first satellite to carry a living animal, a dog named Laika

3. the first active satellite to simultaneously receive and transmit radio signals

4. the first satellite to accomplish a successful transatlantic video transmission

Right Answer : 1
Q15. What development in satellite communications improved back-up power during eclipses?

1. the installation of a battery back-up

2. the installation of a nuclear power source

3. the continuous exposure of solar cells to the sun

4. the increase in solar cells mounted on the surface of the satellite

Right Answer : 4

Q16. CDMA:

1. cannot be used with frequency-hopping spread-spectrum

2. cannot be used with direct-sequence spread-spectrum

3. cannot be used on an RF channel

4. allows many transmitters to use a band simultaneously

Right Answer : 4

Q17. What is the purpose of a telemetry subsystem in a satellite?

1. it is for the wireless link of the earth station and satellite

2. it is for protection purposes such as the radiation from the sun

3. it is for the power supply of the satellite

4. it is for the temperature control inside the satellite

Right Answer : 1

Q18. The key electronic component in a communications satellite is the:

1. telemetry

2. on-board computer

3. command and control system

4. transponder

Right Answer : 4

Q19. Why is satellite orientation in space so important?

1. because it is a necessity for back-up power

2. to meet the requirements of spin stabilization

3. to ensure that sunlight converging on the solar cells is converted to electrical power

4. because it is essential for maximum solar cell exposure to the sun and satellite antenna visibility to earth terminals

Right Answer : 4
Q20. Which of the following characterizes a highly elliptical orbit?

1. an orbit which is circular in shape and inclined with respect to the equator of the earth

2. an orbit with a circular shape and has no inclination, thus it is in line with equator

3. an orbit with a circular shape that has a 90° inclination

4. the apogee and the perigee have large differences

Right Answer : 4

Q21. What is a jet thruster?

1. simply the satellite's engine used to fly

2. removal of satellite from service

3. fired to place the satellite to its final orbit

4. all of these

Right Answer : 1

Q22. Which of the following characteristics is a requirement for a satellite earth terminal antenna?

1. it must be omnidirectional

2. it must be of the franklin collinear type

3. it must have low gain and be highly directional

4. it must be capable of transmitting and receiving signals simultaneously

Right Answer : 4

Q23. Which of the following characterizes a circular inclined orbit?

1. an orbit which is circular in shape and inclined with respect to. the equator of the earth

2. an orbit with a circular shape and has no inclination, thus it is in line with equator

3. an orbit with a circular shape that has a 90° inclination

4. the apogee and the perigee have large differences

Right Answer : 1

Q24. In satellite terminologies, what is a boresight?

1. the term generally associated with a table showing the position of a heavenly body on a number of dates in a
regular sequence

2. it is the geographical representation of a satellite antenna's radiation pattern

3. the direction of maximum gain of an earth station antenna

4. a point on the surface of the earth directly below the satellite

Right Answer : 3
Q25. A satellite stays in orbit because the following two factors are balanced:

1. satellite weight and speed

2. gravitational pull and inertia

3. centripetal force and speed

4. satellite weight and the pull of the moon and sun

Right Answer : 2

Q26. In satellite history, the SCORE:

1. accomplished the first transatlantic transmission using satellite

2. is the first artificial satellite used for relaying terrestrial

3. is the first transponder type satellite

4. is the first space craft to detect the Van Allen radiation belt

Right Answer : 2

Q27. Why do satellite earth terminals require highly sensitive receivers?

1. to overcome the down-link power losses

2. to permit extraction of the desired communications information from the received signal

3. both A and B above

4. because of the signal scatter effect of the antennas

Right Answer : 3

Q28. A LEO satellite system Teledesić:

1. compromises of 66 LEO satellites

2. it consists of 288 satellites

3. it consists of 48 LEO satellite

4. originally consisted of 35 satellites

Right Answer : 2

Q29. What is de-orbit?

1. positioning of the satellite for optimum performance

2. the process of firing the rockets under ground control to maintain or adjust the orbit

3. is an orbit significantly above synchronous orbit, where spacecraft are intentionally placed at the end of their
operational life

4. the process of stopping the thruster of a satellite and letting it fall through the ground

Right Answer : 4
Q30. To a conventional narrowband receiver, an SS signal appears to be like:

1. noise

2. fading

3. a jamming signal

4. an intermittent connection

Right Answer : 1

Q31. What is Telstar I?

1. the first satellite to carry a living animal, a dog named Laika

2. the first active earth satellite

3. the first satellite to accomplish a successful transatlantic video transmission

4. the first active satellite to simultaneously receive and transmit radio signals

Right Answer : 4

Q32. Telemetery equipment used in satellite communications systems performs which of the following functions?

1. they furnish high-capacity wide-band TTY trunks

2. they provide local control for satellite operations

3. they monitor the operating conditions within the satellite

4. they measure ambient weather conditions

Right Answer : 3

Q33. The velocity required to stay in orbit:

1. is higher close to the earth than far from the earth

2. is lower close to the earth than far from the earth

3. is zero (freefall)

4. is constant

Right Answer : 1

Q34. In satellite systems, a space-based architecture:

1. have inter-satellite communication

2. have components and subsystem tasks modularized and divided into separate spacecraft

3. is the most commonly used satellite network architecture

4. all of these

Right Answer : 1
Q35. Which of the following is not a benefit of SS?

1. jam-proof

2. noise proof

3. immunity to fading

4. security

Right Answer : 2

Q36. Which of the following describes the satellite Echo:

1. this is a delayed repeater satellite

2. a passive reflector which is made up of plastic balloon with aluminum coating

3. transmitted telemetry information for nearly 5 months

4. lasted only for 17 days with 3 Watts of transmitted power

Right Answer : 2

Q37. Locating a near-synchronous satellite is rather simple for which of the following reasons?

1. it is stationary

2. it is moving north to south

3. it has a fast relative motion

4. it has a slow relative motion

Right Answer : 4

Q38. An antenna is aimed by adjusting the two "look angles" called:

1. azimuth and declination

2. azimuth and elevation

3. declination and elevation

4. apogee and perigee

Right Answer : 2

Q39. What is the purpose of a power subsystem in a satellite?

1. it is for the optimization control of the antennas

2. it is for protection purposes such as the radiation from the sun

3. it is for the temperature control inside the satellite

4. it is for the power supply of the satellite

Right Answer : 4
Q40. The most critical and difficult part of receiving a direct-sequence SS
signal is:

1. synchronism

2. frequency synthesis

3. PSN code generation

4. carrier recovery

Right Answer : 1

Q41. In an elliptical orbit, when the distance of the satellite to the primary body decreases, satellite's velocity:

1. decreases

2. increases

3. increases by 50%

4. remain unchanged

Right Answer : 2

Q42. Describe a global beam:

1. typically target up to 20% of the earth's surface

2. oncentrate their power to very small geographical areas

3. they are more reliable and flexible

4. radiation patterns of earth coverage antennas have a beamwidth of approximately 17°

Right Answer : 4

Q43. When compared to HF communications, which of the following advantages are unique to satellite
communications links?

1. they are more reliable and flexible

2. they are unaffected by propagation variations affecting HF

3. they do not require repeater stations or troposcatter links

4. each of the above

Right Answer : 4

Q44. What is decommission?

1. fired to place the satellite to its final orbit

2. simply the satellite's engine used to fly

3. removal of satellite from service

4. all of these

Right Answer : 3
Q45. Which of the following factors limits the reliability of active satellite communications system?

1. the reliability of the equipment used

2. the skill of the operating and maintenance personnel

3. the reflection or refraction of signals

4. all of the choices except A

Right Answer : 4

Q46. What is station keeping:

1. the process of firing the rockets under ground control to maintain or adjust the orbit

2. positioning of the satellite for optimum performance

3. is an orbit significantly above synchronous orbit, where spacecraft are intentionally placed at the end of their
operational life

4. the process of stopping the thruster of a satellite and letting it fall through the ground

Right Answer : 1

Q47. The main power sources for a satellite are:

1. batteries

2. fuel cells

3. solar cells

4. thermoelectric generators

Right Answer : 3

Q48. In satellite history, the Courier:

1. accomplished the first transatlantic transmission using satellite

2. is the first artificial satellite used for relaying terrestrial communications

3. is the first space craft to detect the Van Allen radiation belt

4. is the first transponder type satellite

Right Answer : 4

Q49. Which of the following statements best describes the advantage of satellite communications in terms of
flexibility?

1. the antenna group of any earth terminal can be mounted on the weather deck of a ship

2. military satellite communications are capable of handling hundreds of voice channels

3. a high degree of protection from jamming is afforded by the highly directional antennas at earth terminals

4. certain earth terminals are housed in vans and can be

Right Answer : 4
Q50. The minimum number of satellite with polar orbit to cover or to sweep all places around the world:

1. 0

2. 1

3. 2

4. 3

Right Answer : 2

Q51. "Station-keeping" refers to:

1. antenna maintenance

2. power-level adjustments

3. the signal will be more attenuated

4. orbital adjustments

Right Answer : 4

Q52. The satellite subsystem that monitors and controls the satellite is the:

1. propulsion subsystem

2. telemetry, tracking, and command subsystem

3. communications subsystem

4. power subsystem

Right Answer : 2

Q53. The basic technique used to stabilize a satellite is:

1. spin

2. gravity-forward motion balance

3. thruster control

4. solar panel orientation

Right Answer : 1

Q54. Kepler's 3rd Law:

1. it states that the square of the periodic time of orbit is proportional to the cube of the mean distance between the
primary and the satellite

2. it states that for equal intervals of time a satellite will sweep out equal areas in the orbital plane, focused at the
barycenter

3. it states that a satellite will orbit a primary body following an elliptical path

4. none of these

Right Answer : 1
Q55. The jet thrusters are usually fired to:

1. bring the satellite back to earth

2. inject the satellite into, the geosynchronous orbit

3. put the satellite into the transfer orbit

4. maintain attitude

Right Answer : 4

Q56. In an elliptical orbit, when the distance of the satellite to the primary body decreases, satellite's velocity:

1. decreases

2. increases

3. decreases by 50%

4. remain unchanged

Right Answer : 2

Q57. What is a descending node?

1. a point on the circular orbit where the satellite crosses the equator and its move from east to west

2. a point on the circular orbit where the satellite crosses the equator and its move from west to east

3. a point on the circular orbit where the satellite crosses the equator and its move from north to south

4. a point on the circular orbit where the satellite crosses the equator and its move from south to north

Right Answer : 3

Q58. Most commercial satellite activity occurs in which band(s)?

1. C and Ku

2. L

3. S and P

4. X

Right Answer : 1

Q59. Which orbit has the highest altitude?

1. HEO

2. LEO

3. MEO

4. GEO

Right Answer : 4
Q60. Which of the following characterizes an equatorial orbit?

1. an orbit with a circular shape and has no inclination, thus it is in line with equator

2. an orbit which is circular in shape and inclined with respect to the équator of the earth

3. an orbit with a circular shape that has a 90° inclination

4. the apogee and the perigee have large differences

Right Answer : 1

Q61. How can multiple earth stations share a satellite on the same frequencies?

1. frequency reuse

2. multiplexing

3. Mixing

4. They can’t

Right Answer : 1

Q62. A MEO satellite system Ellipso:

1. an orbit with a circular shape that has a 90° inclination

2. a constellation of 21 working satellites and 6 spares orbiting approximately 9500 miles above earth

3. it consists of 10 satellites

4. it initially includes 6 satellites in circular orbit and 8 satellites in elliptical orbit

Right Answer : 4

Q63. MEO satellites orbit___Van Allen belts.

1. between the

2. in the

3. above both

4. below both

Right Answer : 1

Q64. The type of modulation most often used with direct sequence SS is:

1. PSK

2. QAM

3. SSB

4. FSK

Right Answer : 1
Q65. What is an ascending node?

1. a point on the circular orbit where the satellite crosses the equator and its move from east to west

2. a point on the circular orbit where the satellite crosses the equator and its move from west to east

3. a point on the circular orbit where the satellite crosses the equator and its move from north to south

4. a point on the circular orbit where the satellite crosses the equator and its move from south to north

Right Answer : 4

Q66. Which of the following characterizes a polar orbit?

1. an orbit with a circular shape that has a 90° inclination

2. an orbit which is circular in shape and inclined with respect to the equator of the earth

3. an orbit with a circular shape and has no inclination, thus it is in line with equator

4. the apogee and the perigee have large differences,

Right Answer : 1

Q67. In satellite communications, the type of modulation used on voice and video signals is:

1. FM

2. AM

3. SSB

4. QPSK

Right Answer : 1

Q68. One advantage of LEO & MEO satellites is that:

1. it has longer delay times

2. they are available at all times

3. signals are not too attenuated

4. low cost of production

Right Answer : 3

Q69. The ______________is not used for voice communication.

1. IS-95 system

2. GPS

3. Globalstar system

4. Iridium system

Right Answer : 2
Q70. In satellite communications, the modulation normally used with digital data is:

1. AM

2. FM

3. QPSK

4. SSB

Right Answer : 3

Q71. The equator is a:

1. line perpendicular to the equator

2. line parallel to the equator

3. vertical line that runs from north to south

4. horizontal line that runs from west to east

Right Answer : 4

Q72. ___________is often used for navigation purposes.

1. GPS

2. Iridium

3. IS-95

4. AMPS

Right Answer : 1

Q73. Which of the following is not a typical output from a GPS receiver?

1. latitude

2. altitude

3. speed

4. longitude

Right Answer : 3

Q74. Kepler's 2nd Law:

1. it is for protection purposes such as the radiation from the sun

2. it states that the square of the periodic time of orbit is proportional to the cube of the mean distance between the
primary and the satellite

3. it states that a satellite will orbit a primary body following an elliptical path

4. it states that for equal intervals of time a satellite will sweep out equal areas in the orbital plane, focused at the
barycenter

Right Answer : 4
Q75. TDMA is used instead of TDM when:

1. the signals come from different sources

2. TDM is used in RF communications

3. all the signals come from the same source

4. they mean the same thing

Right Answer : 1

Q76. What is the purpose of a structural subsystem in a satellite?

1. it is for the temperature control inside the satellite

2. it is for the power supply of the satellite

3. it is for the wireless link of the earth station and satellite

4. it is for protection purposes such as the radiation from the sun

Right Answer : 4

Q77. Transmission of information to a satellite is done on what frequency?

1. termination

2. transponder

3. down-link

4. up-link

Right Answer : 4

Q78. Which of the following describes a prograde orbit?

1. orbits rotating in the opposite direction as earth's rotation and having an angular velocity less than of the earth

2. orbits having an angular velocity less than of the earth

3. orbits rotating in the opposite direction as earth's rotation

4. orbits rotating in the same direction as earth's rotation

Right Answer : 4

Q79. A LEO satellite has___orbit.

1. an inclined

2. an equatorial

3. a polar

4. all of the above

Right Answer : 1
Q80. Which of the following is not usually a part of a transponder?

1. LNA

2. modulator

3. mixer

4. HPA

Right Answer : 2

Q81. An earth terminal receives signals on what frequency?

1. down-link

2. termination

3. transmit

4. up-link

Right Answer : 1

Q82. Spread-spectrum can be done by using:

1. crosspoint switch

2. computerized Strowger switch

3. frequency-hopping

4. computer-controlled frequency reuse

Right Answer : 1

Q83. Describe a spot beam:

1. concentrate their power to very small geographical areas

2. typically target up to 20% of the earth's surface

3. radiation patterns of earth coverage antennas have a beamwidth of approximately 17°

4. all of these

Right Answer : 1

Q84. In satellite terminologies, what is a footprint?

1. a point on the surface of the earth directly below the satellite

2. the direction of maximum gain of an earth station antenna

3. the term generally associated with a table showing the position of a heavenly body on a number of dates in a
regular sequence

4. it is the geographical representation of a satellite antenna's radiation pattern

Right Answer : 4
Q85. The satellite communications channels in a transponder are defined by the:

1. input signals

2. mixer

3. bandpass filter

4. LNA

Right Answer : 3

Q86. The satellite SYNCOM I:

1. concentrate their power to very small geographical areas

2. was used to telecast the 1964 Summer Olympics in Tokyo

3. is the first geosynchronous satellite

4. lost on the way to geosynchronous orbit due to an electronics failure

Right Answer : 4

Q87. In order to cover most of the earth except the polar regions, what is the minimum number of satellites that
mast be orbited?

1. 3

2. 4

3. 5

4. 6

Right Answer : 1

Q88. For a given data rate, direct-sequence systems, compared to standard RF systems, use:

1. much less bandwidth

2. about the same bandwidth

3. much more bandwidth

4. approximately double the bandwidth

Right Answer : 3

Q89. What is an apogee kick motor?

1. simply the satellite's engine used to fly

2. fired to place the satellite to its final orbit

3. removal of satellite from service

4. all of these

Right Answer : 2
Q90. In satellite terminologies, what is an ephemeris?

1. a point on the surface of the earth directly below the satellite

2. the direction of maximum gain of an earth station antenna

3. it is the geographical representation of a satellite antenna's radiation pattern

4. the term generally associated with a table showing the position of a heavenly body on a number of dates in a
regular sequence

Right Answer : 4

Q91. The HPAs in most satellites are:

1. magnetrons

2. vacuum tubes

3. klystrons

4. TWTs

Right Answer : 3

Q92. Why does the downlink frequency appear to vary by several kHz during a low earth orbit satellite pass?

1. the distance between the satellite and ground station is changing, causing the Boyle's law effect

2. the distance between the satellite and ground station is changing, causing the Bernoulli effect

3. the distance between the satellite and ground station is changing, causing the Doppler effect

4. the distance between the satellite and ground station is changing, causing the Kepler effect

Right Answer : 3

Q93. The Agila Il consists of:

1. 24 C-band transponders at 27 Watts and 40 Ku-band transponders at 110 Watts

2. 24 C-band transponders at 27 Watts and 30 Ku-band transponders at 110 Watts

3. 40 C-band transponders at 27 Watts and 24 Ku-band transponders at 110 Watts

4. 30 C-band transponders at 27 Watts and 24 Ku-band transponders at 110 Watts

Right Answer : 4

Q94. A satellite communications system is limited by which of the following characteristics?

1. the attitude of the satellite repeater

2. the immobility of the satellite

3. the mobility of the satellite

4. the technical design of the satellite

Right Answer : 4
Q95. Which of the following does not hold true for a Geostationary satellite?

1. travel in the same direction as earth's rotation at 6840 m/s

2. located directly above the equator

3. have an altitude of 22300 miles above the earth

4. complete one revolution in 24 hours

Right Answer : 1

Q96. In satellite terminologies, what is an SSP?

1. a point on the surface of the earth directly below the satellite

2. the direction of maximum gain of an earth station antenna

3. it is the geographical representation of a satellite antenna's radiation pattern

4. the term generally associated with a table showing the position .of a heavenly body on a number of dates in a
regular sequence

Right Answer : 1

Q97. Batteries are used to power all satellite subsystems:

1. at all times

2. only during emergencies

3. to give the solar arrays a rest

4. during eclipse periods

Right Answer : 4

Q98. The satellite SYNCOM II:

1. lost on the way to geosynchronous orbit due to an electronics

2. was used to telecast the 1964 Summer Olympics in Tokyo

3. is the first geosynchronous satellite

4. all of these

Right Answer : 3

Q99. Active communications satellite systems have two major limitations. What are they?

1. down-link transmitter power and uplink receiver sensitivity

2. up-link transmitter power and earth terminal antenna size

3. complex preamplifiers and high gain antennas

4. down-link receiver sensitivity and external atmospheric noise

Right Answer : 1
Q100. Disadvantage of using GEO satellites:

1. it has to be maintained all the time

2. signals are less attenuated

3. shorter delay times

4. they are not available at all times

Right Answer : 1

Q101. A reduction in TWT power for linearity is called:

1. backdown

2. power down

3. backoff

4. EIRP drop

Right Answer : 3

Q102. Which microwave tube is used for satellites?

1. travelling wave tube

2. magnetron'

3. reflex klystron

4. klystron

Right Answer : 1

Q103. The physical location of a satellite is determined by its:

1. distance from the earth

2. reference to the stars

3. latitude and longitude

4. position relative to the sun

Right Answer : 3

Q104. The RF power output of a satellite communications system is severely limited due to which of the following
factors?

1. a lack of adequate jamming capabilities

2. a requirement for large antenna-farm earth-terminal systems

3. an unstable satellite orientation with respect to the horizon

4. an inefficient solar-cell package aboard the satellite

Right Answer : 4
Q105. The angle of inclination required to have a rotation of line of apsides equal to zero:

1. 63.4 degrees

2. 36.4 degrees

3. 33.4 degrees

4. 66.4 degrees

Right Answer : 1

Q106. At least____GEO satellites are needed to cover almost the surface of the earth except for the poles.

1. 3

2. 2

3. 1

4. 0

Right Answer : 1

Q107. The receive GCE system in an earth station-performs what function(s)?

1. demodulation and demultiplexing

2. modulation and multiplexing

3. up conversion

4. down conversion

Right Answer : 1

Q108. The Agila II is a __________satellite.

1. MEO

2. GEO

3. HEO

4. LEO

Right Answer : 2

Q109. The availability of a satellite to act as a relay station between two earth terminals depends upon which of the
following considerations?

1. the mobility of the satellite

2. the location of the earth terminals

3. the operating frequencies of the satellite

4. the electronic design of the earth terminals

Right Answer : 2
Q110. In satellite systems, a fractionated satellite:

1. have inter-satellite communication

2. have components and subsystem tasks modularized and divided into separate spacecraft

3. is the most commonly used satellite network architecture

4. all of these

Right Answer : 2

Q111. Which of the following types of HPA is not used in earth stations?

1. TWT

2. transistor

3. klystron

4. magnetron

Right Answer : 4

Q112. In satellite history, the Explorer I:

1. accomplished the first transatlantic transmission using satellite

2. is the first artificial satellite used for relaying terrestrial communications

3. is the first transponder type satellite

4. is the first space craft to detect the Van Allen Radiation Belt

Right Answer : 4

Q113. What determines the length of time that a nonsynchronous satellite in a circular orbit will be in the zone of
mutual visibility?

1. height of the orbit

2. earth terminal antenna size

3. down-link transmitter power

4. up-link receiver sensitivity

Right Answer : 1

Q114. The latitude is a:

1. horizontal line that runs from west to east

2. vertical line that runs from north to south

3. line parallel to the equator

4. line perpendicular to the equator

Right Answer : 3
Q115. For real-time communication, LEO systems require:

1. line parallel to the equator

2. very high power

3. tracking dish antennas

4. a constellation of satellites

Right Answer : 4

Q116. Kepler's 1st Law:

1. it states that for equal intervals of time a satellite will sweep out equal areas in the orbital plane, focused at the
barycenter

2. it states that the square of the periodic time of orbit is proportional to the cube of the mean distance between the
primary and the satellite

3. proportional to the cube of the mean distance between the primary and the satellite

4. it states that a satellite will orbit a primary body following an elliptical path

Right Answer : 4

Q117. A common up-converter and down-converter IF is:

1. 36 MHz

2. 70 MHz

3. 40 MHz

4. 500 MHz

Right Answer : 3

Q118. One disadvantage of LEO & MEO satellites is that:

1. they have longer delay times

2. signals are too attenuated

3. they are available at all times

4. high cost of production

Right Answer : 4

Q119. Which of the following describes a retrograde orbit?

1. orbits rotating in the same direction as earth's rotation and having an angular velocity greater than of the earth

2. orbits rotating in the opposite direction as earth's rotation

3. orbits having an angular velocity greater than of the earth

4. orbits rotating in the opposite direction as earth's rotation and having an angular velocity greater than of the earth

Right Answer : 2
Q120. What is the purpose of an attitude and orbit controlled control subsystem in a satellite?

1. it is for the optimization control of the antennas

2. it is for protection purposes such as the radiation from the sun

3. it is for the power supply of the satellite

4. it is for the temperature control inside the satellite

Right Answer : 1

Q121. Which of the following is the first active satellite?

1. Echo I

2. Telstar I

3. Early Bird

4. Sputnik I

Right Answer : 4

Q122. Which of the following is the first commercial satellite?

1. Early Bird

2. Explorer

3. Courier View

4. Telstar

Right Answer : 4

Q123. What is the first passive satellite transponder?

1. Sun

2. Early Bird

3. Score

4. Moon

Right Answer : 2

Q124. The first satellite to receive and transmit simultaneously

1. Intelsat I

2. Agila I

3. Telstar I

4. Syncorn I

Right Answer : 3
Q125. A helical antenna is used for satellite tracking because of

1. gain

2. beamwidth

3. maneuverability

4. circular polarization

Right Answer : 4

Q126. Repeaters inside communications satellites are known as

1. Trancievers

2. Transponders

3. Transducers

4. TWT

Right Answer : 2

Q127. Considered as the unsolved problem in satellite system

1. Coverage

2. Cost

3. Privacy

4. Access

Right Answer : 3

Q128. ________________ is a satellite that rotates around the earth in a low-altitude elliptical or circular pattern.

1. Geosynchronous satellite

2. Prograde satellite

3. Retrograde satellite

4. Nonsynchronous satellite

Right Answer : 4

Q129. Is the geographical representation of a satellite antenna radiation pattern.

1. Spot

2. Earth

3. Region

4. Footprint

Right Answer : 4
Q130. The smallest beam of a satellite antenna radiation pattern

1. Zone beam

2. Hemispheric beam

3. Global beam

4. Spot beam

Right Answer : 4

Q131. The main function of a communications satellite is a/ an

1. observation platform

2. beacon

3. reflector

4. repeater

Right Answer : 4

Q132. The key electronic component in a communications satellite is the ___________.

1. telemetry equipment

2. on-board computer

3. transponder

4. command and control system

Right Answer : 3

Q133. A circular orbit around the equator with a 24-h period is called a/an _____________.

1. elliptical orbit

2. polar orbit

3. transfer orbit

4. geostationary orbit

Right Answer : 4

Q134. A satellite stay in orbit because the following two factors are balanced

1. Satellite weight and speed

2. Centripetal force and speed

3. Gravitational force and centrifugal force

4. Satellite weight and the pull of the moon and sun

Right Answer : 3
Q135. What is the basic technique used to stabilize a satellite?

1. Spin

2. Gravity-forward motion balance

3. Thruster control

4. Solar panel orientation

Right Answer : 1

Q136. Which of the following is not usually a part of a transponder are defined by the ____________.

1. LNA

2. Mixer

3. Modulator

4. HPA

Right Answer : 3

Q137. The receive GCE system in an earth station performs what function(s)?

1. Modulation and multiplexing

2. Up conversion

3. Demodulation and demultiplexing

4. Down conversion

Right Answer : 3

Q138. The maximum propagation delay of a geostationary satellite is ___________.

1. 250 ms

2. 300 ms

3. 239 ms

4. 278 ms

Right Answer : 4

Q139. The total propagation delay time from transmission to reception of signals from a ground transmitter to
ground receiver with angle of elevation at 10 degrees respectively is ___________.

1. 260 ms

2. 275 ms

3. 239 ms

4. 273 ms

Right Answer : 4
Q140. It is a celestial body that orbits around a planet.

1. Primary body

2. Heavenly bodies

3. Quasars View

4. Satellite

Right Answer : 4

Q141. The geometric shape of a non-circular orbit of a satellite is_______________.

1. Paraboloid

2. Hyperbolic

3. Parabolic

4. Ellipse

Right Answer : 4

Q142. The circuit that provides channelization in a transponder is the ____________.

1. Mixer

2. Bandpass filter

3. Local oscillator

4. HPA

Right Answer : 2

Q143. The three axes referred to the three-axis attitude stabilization are; except______________.

1. Speed

2. Roll

3. Yaw

4. Pitch

Right Answer : 1

Q144. The escape velocity of the earth is approximately _____________________.

1. 25,000 mi/hr

2. 30,000 km/hr

3. 35,000 m/s

4. 25,000 km/hr

Right Answer : 1
Q145. It is caused by the inertia of the satellite balanced by the earth’s gravitational pull.

1. Centripetal force

2. Centrifugal force

3. Speed

4. Earth’s rotation

Right Answer : 1

Q146. The law that states that a satellite will orbit a primary body following an elliptical path.

1. 4th law of Kepler

2. 3rd law of Kepler

3. 2nd law of Kepler

4. 1st law of Kepler

Right Answer : 4

Q147. Kepler’s 2nd law is known as ___________________.

1. Newton’s law of motion

2. Law of gravity

3. Law of areas

4. Harmonic law

Right Answer : 3

Q148. A common up-converter and down-converter IF in satellite communications is _________.

1. 36 MHz

2. 40 MHz

3. 50 MHz

4. 70 MHz

Right Answer : 4

Q149. It is the angle between the earth’s equatorial plane and the orbital plane of the satellite measured
counterclockwise.

1. Angle of inclination

2. Angle of tetrahedron

3. Angle of azimuth

4. Angle of elevation

Right Answer : 1
Q150. Which of the following types of HPA is not used in earth stations?

1. TWT

2. Klystron

3. Transistors

4. Magnetron

Right Answer : 4

Q151. The point where a polar or inclined orbit crosses the equatorial plane traveling from north to south.

1. Ascending node

2. Line of nodes

3. Descending node

4. Diagonal nodes

Right Answer : 3

Q152. The receive GCE system in an earth station performs what function/s _________.

1. Modulation and multiplexing

2. Up conversion

3. Demodulation and demultiplexing

4. Down conversion

Right Answer : 3

Q153. The term generally associated with the table showing the position of a heavenly body on the number of dates
in a regular sequence.

1. Astronomical almanac

2. Ephemeris

3. Smith

4. Space reporting

Right Answer : 2

Q154. The point where a polar or inclined orbit crosses the equatorial plane traveling from south to north.

1. Ascending node

2. Descending node

3. Diagonal node

4. Inclined node

Right Answer : 1
Q155.
When the satellite rotates in an orbit directly above the equator, usually in circular pattern. This type of orbit is called
____________________.

1. Equatorial orbit

2. Geosynchronous satellite

3. Synchronous orbit

4. Polar orbit

Right Answer : 1

Q156. The HPAs in most satellites are _________________.

1. Vacuum tubes

2. TWTs

3. Klystrons

4. Magnetrons

Right Answer : 2

Q157. The azimuth angles and the angle of elevation is collectively known as ________________.

1. Antennas satellite angles

2. Antennas keep angles

3. Antennas see angles

4. Antennas look angles

Right Answer : 4

Q158. The point on the surface of the Earth directly below the satellite.

1. Satellite point

2. Latitude

3. Longitude

4. Subsatellite point

Right Answer : 4

Q159. It is the vertical angle formed between the direction of travel of an electromagnetic wave radiated from an
earth station antenna pointing directly toward a satellite and the horizontal plane.

1. Angle of depression

2. Angle of

3. Angle of elevation

4. Angle of azimuth

Right Answer : 3
Q160. Navstar GPS satellite grouping capable of detecting certain error conditions, then automatically transmitting a
coded message indicating that it is out of service.

1. Block I

2. Block IIa

3. Block II

4. Block IIR

Right Answer : 3

Q161. Galileo Satellites has a lifespan of _____________________.

1. greater than 25 years

2. greater than 20 years

3. greater than 15 years

4. greater than 12 years

Right Answer : 4

Q162. The height of a satellite in a synchronous equatorial orbit is ______________.

1. 100 mi

2. 6800 mi

3. 22,300 mi

4. 35,860 mi

Right Answer : 3

Q163. An orbit that is 36,000 km away from the geocenter of the earth is called _____________.

1. Geosynchronous orbit

2. Clarke orbit

3. Geostationary orbit

4. Any of these

Right Answer : 4

Q164. A circular orbit around the equator with 24-h period is called

1. Elliptical orbit

2. Geostationary orbit

3. Polar orbit

4. Transfer orbit

Right Answer : 2
Q165. A classification of satellite that uses the angular momentum of its spinning body to provide roll and yaw
stabilization.

1. Roll stabilizer satellite

2. Yaw stabilizer satellite

3. Spinner stabilizer satellite

4. Three-axis stabilizer satellite

Right Answer : 3

Q166. The main power sources for a satellite are _____________.

1. Batteries

2. Solar cells

3. Fuel cells

4. Thermoelectric generators

Right Answer : 2

Q167. A type of satellite’s multiple-accessing method that allows all users continuous and equal access of the entire
transponder bandwidth by assigning carrier frequencies on a temporary basis using statistical assignment process.

1. TDMA

2. FDMA

3. DAMA

4. CDMA

Right Answer : 3

Q168. Galileo satellite system is positioned in ___________________.

1. 6 circular orbits

2. 2 circular orbits

3. 3 circular orbits

4. 5 circular orbits

Right Answer : 3

Q169. A navigation technique that determines position by extrapolating a series of measured velocity increments.

1. Piloting

2. Wandering

3. Radio navigation

4. Dead reckoning

Right Answer : 4
Q170. A geostationary satellite _________________________.

1. Is motionless in space (except for its gain)

2. Is not really stationary at all, but orbits the Earth within a 24-hr period

3. Appears stationary over the Earth’s magnetic pole

4. Is located at a height of 35,800 km to ensure global coverage

Right Answer : 2

Q171. The GPS satellites has an angle of elevation at the ascending node of with respect to the equatorial plane.

1. 30 degrees

2. 55 degrees

3. 50 degrees

4. 45 degrees

Right Answer : 2

Q172. Who is the oldest man in space?

1. Neil Armstrong

2. Yuri Gagarin

3. John Glenn

4. Edwin Aldrin

Right Answer : 3

Q173. What kind of battery panels are used in some advance satellites?

1. Gallium Phosphate solar panel

2. Germanium based panels

3. Silicon based panels

4. Gallium Arsenide solar panel

Right Answer : 4

Q174. Footprint refers to coverage area in the globe ¬_____________________.

1. Satellite navigation

2. Satellite radiation pattern

3. Satellite coverage

4. Satellite radiation polarization

Right Answer : 2
Q175. The first passive satellite transponder ____________________.

1. Early bird

2. Score

3. Star

4. Moon

Right Answer : 4

Q176. Satellite used for intercontinental communications are known as _____________________.

1. Marisat

2. Intelsat

3. Domsat

4. Comsat

Right Answer : 2

Q177. Refers to the man-made body sent into continuous orbit around the earth, which provides propagation paths
for radio waves between terrestrial transmitters and receivers.

1. Communication satellite

2. Space shuttle

3. Allotter relay

4. Rocket

Right Answer : 1

Q178. What is the basic function of a communications satellite?

1. To act as a receiving antenna for broadcast FM

2. To compensate for the antenna limitations

3. To eliminate aerodynamic drag

4. To acts as receiving antenna for broadcast AM

Right Answer : 2

Q179. Which of the following is not an advantage of geosynchronous orbit?

1. No need to switch from one satellite to another as satellites orbit overhead, therefore, no breaks of transmission
due to switching times.

2. High-altitude geosynchronous satellites can cover a much larger area

3. Satellite remains almost stationary in respect to a given earth station, therefore, expensive tracking equipment is
not required at the earth stations.

4. Geosynchronous satellites require higher transmit powers and more sensitive receivers because of the longer
distances and greater path loss.

Right Answer : 4
Q180. There are two primary classifications of communications satellite; one uses the angular momentum of its
spinning body to provide roll and yaw relative to earth’s surface while an internal subsystem provides roll and yaw
stabilization. What are they?

1. spinners and three-axis stabilizer satellites

2. passive and active satellites

3. delayed repeater satellites

4. gyroscopic satellites

Right Answer : 1

Q181. A ________________________ satellite with an orbital period of one sidereal day or nominally, 24 h

1. Bent-pipe satellite

2. Processing satellite

3. Geostationary satellite

4. ANIK-D communications satellite

Right Answer : 3

Q182. Polar and inclined orbits refer to what?

1. Any other orbital path, and rotation above the equator, respectively

2. Any other orbital path, and rotation that takes over the north and south poles, respectively

3. Rotation above the equator, and rotation that takes over the north and south poles, respectively

4. Rotation that takes over the north and south poles, and any other orbital path, respectively

Right Answer : 4

Q183.
__________________ means the farthest distance from earth a satellite orbit reaches while ___________________
is the minimum distance.

1. a. Apogee and perigee, respectively

2. b. Perigee and apogee, respectively

3. c. A and B are the same

4. d. None of these

Right Answer : 1

Q184. Refers to the line joining the perigee and apogee through the center of the earth

1. Line of sight

2. Line of nodes

3. Equatorial nelt

4. Line of apsides

Right Answer : 4
Q185. The point where the orbit crosses the equatorial plane going from north to south; and the point where the
orbit crosses the equatorial plane going from south to north refer to ____________.

1. Descending node and ascending node, respectively

2. Ascending node and descending node, respectively

3. Descending node

4. Ascending node

Right Answer : 1

Q186. Refers to the horizontal pointing of an antenna.

1. Look angle

2. Azimuth

3. Elevation

4. Spot

Right Answer : 2

Q187. What is meant by the angle of elevation?

1. a. The angle formed between the direction of travel of a wave radiated from an earth station antenna and the
horizontal.

2. b. The horizontal pointing of an antenna

3. c. The angle subtended at the earth station antenna between the satellite and the horizontal

4. d. A or C is right

Right Answer : 4

Q188. The range of frequencies used by communications satellites?

1. From 1 GHz up to 30 GHz

2. From 1 GHz up to 3 GHz

3. From 30 GHz up to 300 GHz

4. From 300 GHz up to 350 GHz

Right Answer : 1

Q189. Otherwise considered as radio repeater in the sky.

1. Courier

2. Sputnik

3. Transponder

4. Satellite

Right Answer : 3
Q190. What do you call of the signal path from the transmitter to satellite and from the satellite to earth-based
receiver?

1. Downlink and uplink, respectively

2. Downlink

3. Uplink and downlink, respectively

4. Uplink

Right Answer : 3

Q191. What is meant by link budget?

1. a. The sum of all the signal gains and losses along the way.

2. b. The difference of the signal gains and losses along the way

3. c. Identifies the system parameters and is used to determine the projected C/N and Eb/No ratios at both the
satellite and earth stations receivers for a given modulation scheme and desired Pq.

4. d. A or C is right

Right Answer : 4

Q192. A satellite consists of any subsystem functions incorporated into a single system. What is the subsystem
responsible for providing the primary dc power and the regulated, secondary supply voltages for the satellite
circuits?

1. Communication channel subsystem

2. Telemetry subsystem

3. Power subsystem

4. Antennas

Right Answer : 3

Q193. How do communications satellites powered?

1. AC power View

2. Nuclear

3. Liquid fuel

4. By a bank of batteries whose charge is maintained by an array of solar cells

Right Answer : 4

Q194. ____________________ is the total power consumption for the satellite operation?

1. About 10 W

2. About 150 W

3. About 2000 W

4. About 25000 W

Right Answer : 2
Q195. As the height of a satellite orbits gets lower, the speed of the satellite _________________.

1. None

2. Remains the same

3. Decreases

4. Increases

Right Answer : 4

Q196. A satellite stays in orbit because the following two factors are balanced.

1. Satellite weight and speed

2. Centripetal force and speed

3. Satellite weight and the pull of the moon and sun

4. Gravitational pull and inertia

Right Answer : 4

Q197. The height of a satellite in a synchronous equatorial orbit is __________________.

1. 100 mi

2. 6800 mi

3. 22,300 mi

4. 35, 860 mi

Right Answer : 3

Q198. The satellite subsystems that monitors and controls the satellite is the ___________________.

1. Propulsion subsystem

2. Communications subsystem

3. Telemetry, tracking, and command subsystem

4. Propulsion subsystem

Right Answer : 3

Q199. Most commercial satellite activity occurs in which band(s)?

1. L

2. S and P View

3. X

4. C and Ku

Right Answer : 4
Q200. It is caused by the inertia of the satellite balanced by the earth’s gravitational pull.

1. Centripetal force

2. Speed

3. Earth’s rotation

4. Centrifugal force

Right Answer : 1

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