Thursday, 23 November 2017

SATELLITE COMMUNICATION | INTERVIEW QUESTIONS AND ANSWERS

By Ask Biomedical


1. Which of the following is the first active satellite?
A. Echo I
B. Telstar I
C. Early Bird
D. Sputnik I

2.Which of the following is the first commercial satellite?
A. Early Bird
B. Telstar
C. Explorer
D. Courier

3. What is the first passive satellite transponder?
A. Sun
B. Early Bird
C. Score
D. Moon

4. The first satellite to receive and transmit simultaneously
A. Intelsat I
B. Agila I
C. Syncorn I
D. Telstar I

5. A helical antenna is used for satellite tracking because of
A. circular polarization
B. maneuverability
C. beamwidth
D. gain

6. Repeaters inside communications satellites are known as
A. Trancievers
B. Transponders
C. Transducers
D. TWT

7. Considered as the unsolved problem in satellite system
A. Coverage
B. Cost
C. Access
D. Privacy

8. ___________ is a satellite that rotates around the earth in a
low-altitude elliptical or circular pattern.
A. Geosynchronous satellite
B. Nonsynchronous satellite
C. Prograde satellite
D. Retrograde satellite

9. Is the geographical representation of a satellite antenna
radiation pattern
A. Footprint
B. Spot
C. Earth
D. Region

10. The smallest beam of a satellite antenna radiation pattern
A. Zone beam
B. Hemispheric beam
C. Spot beam
D. Global beam

11. A satellite beam that covers almost 42.4% of the earths
surface.
A. Zone beam
B. Hemispheric beam
C. Spot beam
D. Global beam

12. What is the frequency range of C-band?
A. 8.5 to 12.5 GHz
B. 3.4 to 6.425 GHz
C. 12.95 to 14.95 GHz
D. 27.5 to 31 GHz

13. A satellite signal transmitted from a satellite transponder to
earth’s station.
A. Uplink
B. Downlink
C. Terrestrial
D. Earthbound

14. Collects very weak signals from a broadcast satellite
A. Helical antenna
B. Satellite dish
C. LNA
D. TWT

15. What is a device that detects both vertically and horizontally
polarized signals simultaneously?
A. Orthomode transducer
B. Crystal detector
C. Optoisolator
D. Isomode detector

16. _________ detects the satellite signal relayed from the
feed and converts it to an electric current, amplifies and lower
its frequency.
A. Horn antenna
B. LNA
C. Satellite receiver
D. Satellite dish

17. Is a loss of power of a satellite downlink signal due to earth’s
atmosphere.
A. Atmospheric loss
B. Path loss
C. Radiation loss
D. RFI

18. What height must a satellite be placed above the surface of
the earth in order for its rotation to be equal to earth’s rotation?
A. 26,426.4 miles
B. 27,426.4 miles
C. 23,426.4 miles
D. 22,426.4 miles

19. Point on the satellite obits closest to the earth.
A. Apogee
B. Perigee
C. Prograde
D. Zenith

20. The earth area covered by a satellite radio beam.
A. Beamwidth
B. Bandwidth
C. Footprint
D. Zone

21. What is the local oscillator (mixer) frequency of the satellite
with an uplink frequency in GHz band?
A. 3500 MHz
B. 4500 MHz
C. 2225 MHz
D. 2555 MHz

22. What kind of battery panels are used in some advance
satellites
A. Germanium based panels
B. Silicon based panel
C. Galium Phosphate solar panel array
D. Galium Arsenide solar panel array

23. Satellite engine uses
A. jet propulsion
B. ion propulsion system
C. liquid fuel
D. solar jet

24. A satellite batter has more power but lighter.
A. Lithium
B. Leclanche
C. Hydrogen
D. Magnesium

25. What kind of battery used by older satellites?
A. Lithium
B. Leclanche
C. Hydrogen
D. Magnesium

26. VSAT was made available in
A. 1979
B. 1981
C. 1983
D. 1977

27. What band does VSAT first operate?
A. L-band
B. X-band
C. C-band
D. Ku-band

33. The owner of AsiaSat 2 is
A. Asia Satellite Telecommunications Company (ASTC)
B. Japan Satellite System (JSAT)
C. China Great Wall Industry Corporation
D. Singapore Satellite Commision

34. What is the approximate path loss from satellite-to-earth
station?
A. 100 dB
B. 150 dB
C. 175 dB
D. 200 dB

35. INTELSAT stands for
A. Intel Satellite
B. International Telephone Satellite
C. International Telecommunications Satellite
D. International Satellite

36. The frequency of Ku band for satellite communications.
A. 6/4 GHz
B. 14/11 GHz
C. 12/14 GHz
D. 4/8 GHz

37. A satellite cross-link means
A. Earth-to-satellite link
B. Satellite-to-earth link
C. Satellite-to-satellite link
D. None of these

38. Earth station uses what type of antenna
A. Despun antenna
B. Helical antenna
C. Toroidal antenna
D. Cassegrain antenna

39. What is the delay time for satellite transmission from earth
transmitter to earth receiver?
A. 0.5 s
B. 1.0 s
C. 5 ms
D. 0.25 ms

40. The bandwidth of C-band satellite frequency band in U.S.
A. 500 GHz
B. 1000 GHz
C. 1000 MHz
D. 500 MHz

41. The most common device used as an LNA is
A. zener diode
B. tunnel diode
C. IMPATT
D. Shockley diode

42. The radiation patterns of earth coverage antennas have abeamwidth of approximately
A. 21˚
B. 5˚
C. 17˚
D. 35˚

ANSWERS:-
1. Sputnik I
2. Telstar
3. Early Bird
4. Telstar I
5. circular polarization
6. Transponders
7. Privacy
8. Nonsynchronous satellite
9. Footprint
10. Spot beam
11. Global beam
12. 3.4 to 6.425 GHz
13. Downlink
14. Satellite dish
15. Orthomode transducer
16. LNA
17. Path loss
18. 22,426.4 miles
19. Perigee
20. Footprint
21. 2225 MHz
22. Galium Arsenide solar panel array
23. ion propulsion system
24. Lithium
25. Hydrogen
26. 1979
27. C-band

33. China Great Wall Industry Corporation
34. 200 dB
35. International Telecommunications Satellite
36. 14/11 GHz
37. Satellite-to-satellite link
38. Cassegrain antenna
39. 0.5 s
40. 500 MHz
41. tunnel diode
42. 17˚

0 comments:

Post a Comment