Blake: MCQ in Satellite Communications

This is the Multiple Choice Questions in Chapter 20: Satellite Communications from the book Electronic Communication Systems by Roy Blake. If you are looking for a reviewer in Communications Engineering this will definitely help. I can assure you that this will be a great help in reviewing the book in preparation for your Board Exam. Make sure to familiarize each and every questions to increase the chance of passing the ECE Board Exam.

See also: MCQ in Electronic Communication Systems by George Kennedy

Start Practice Exam Test Questions

Choose the letter of the best answer in each questions.

MULTIPLE CHOICE

1. The height of the geosynchronous orbit above the equator is about:

a. 3,578 km

b. 35,780 km

c. 357,800 km

d. depends on satellite velocity

2. The high and low points of a satellite’s orbit are called, respectively,:

a. apogee and perigee

b. perigee and apogee

c. uplink and downlink

d. downlink and uplink

3. The area on the earth that is “covered” by a satellite is called its:

a. earth station

b. downlink

c. footprint

d. plate

4. The velocity required to stay in orbit:

a. is constant

b. is zero (freefall)

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

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

5. An antenna is aimed by adjusting the two “look angles” called:

a. azimuth and elevation

b. azimuth and declination

c. declination and elevation

d. apogee and perigee

6. The power per transponder of a typical Ku-band satellite is in the range:

a. 5 to 25 watts

b. 50 to 250 watts

c. 500 to 2500 watts

d. depends on its orbit

7. The power level for an earth station to transmit to a satellite is on the order of:

a. 101 watts

b. 102 watts

c. 103 watts

d. 104 watts

8. The “payload” on a communications satellite consists of:

a. transponders

b. batteries

c. solar cells

d. all of the above

9. “Station-keeping” refers to:

a. antenna maintenance

b. power-level adjustments

c. orbital adjustments

d. none of the above

10. DBS stands for:

a. decibels of signal

b. down-beam signal

c. direct-broadcast system

d. direct-broadcast satellite

11. LNA stands for:

a. low-noise amplifier

b. low north angle

c. low-noise amplitude

d. low-noise array

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

a. backdown

b. backoff

c. power-down

d. EIRP drop

13. TVRO stands for:

a. television receive only

b. television repeater only

c. television remote origin

d. none of the above

14. TDMA stands for:

a. transponder-directed multiple antennas

b. television distribution master antenna

c. time-division multiple access

d. transmit delay minimum aperture

15. VSAT stands for:

a. video satellite

b. video signal antenna terminal

c. very small antenna terminal

d. very small aperture terminal

16. On the uplink from a terminal, a VSAT system uses:

a. high power to a small antenna

b. low power to a small antenna

c. low power to a large antenna

d. LEO satellites

17. A typical VSAT system is configured as a:

a. star

b. mesh

c. ring

d. repeater

18. LEO stands for:

a. long elliptic orbit

b. low-earth orbit

c. lateral earth orbit

d. longitudinal earth orbit

19. For real-time communication, LEO systems require:

a. a constellation of satellites

b. tracking dish antennas

c. very high power

d. all of the above

20. The frequency bands used by Ku-band satellites are:

a. 4 GHz and 6 GHz

b. 12 GHz and 14 GHz

c. 20 GHz and 30 GHz

d. none of the above

COMPLETION

1. A satellite in geosynchronous orbit takes ____________________ hours to complete one orbit.

2. The ____________________ is the signal path from the earth station to the satellite.

3. The ____________________ is the signal path from the satellite to the earth station.

4. A satellite in a ____________________ orbit appears to stay directly above one spot on the equator.

5. Non-geostationary satellites are sometimes called ____________________ satellites.

6. A geosynchronous orbit is about ____________________ km above the earth.

7. A ____________________ is an outline of the area on the earth’s surface that a satellite broadcasts to.

8. All satellite orbits are ____________________ in shape.

9. The ____________________ is the distance of a satellite’s closest approach to the earth.

10. The ____________________ is a satellite’s farthest distance from the earth.

11. An antenna’s ____________________ is its angular direction between east and west.

12. An antenna’s ____________________ is its vertical angle with respect to the earth’s surface.

13. An antenna’s ____________________ is the angle by which it is offset from the earth’s axis.

14. Satellites using the ____________________ band operate on 12 GHz.

15. The time for a signal to make a round trip via satellite is about ____________________ milliseconds.

16. A ____________________ is a type of repeater used on communications satellites.

17. Both the gain and the beamwidth of a dish antenna depend on its ____________________.

18. VSAT systems commonly use a ____________________ network configuration.

19. To date, LEO satellite systems have been a financial ____________________.

20. C-band antennas are ____________________ than Ku-band antennas.

SHORT ANSWER

1. A receiving antenna with a gain of 44.4 dBi looks at a sky with a noise temperature of 15 K. The loss between the output of the antenna and the input of the LNA is 0.4 dB, and the LNA has a noise temperature of 40 K. Calculate the G/T.

2. A receiver has a noise figure of 1.7 dB. Find its equivalent noise temperature.

3. A receiving antenna with a G/T of 25 dB is used to receive signals from a satellite 38,000 km away. The satellite has a 100-watt transmitter and an antenna with a gain of 30 dBi. The signal has a bandwidth of 1 MHz at a frequency of 12 GHz. Calculate the C/N at the receiver.

Complete List of MCQ in Electronic Communication Systems by Blake