While keeping the down-link frequency constant, the diameter of a satellite ante

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Question
While keeping the down-link frequency constant, the diameter of a satellite antenna is reduced by half. To offer the same EIRP over the increased coverage area, the RF output power has to be increases by a factor of
Options
A. 2
B. 4
C. 8
D. 16

Correct Answer

1. In satellite communication, frequency modulation is used because satellite channel has
Options
A. small bandwidth and negligible noise
B. large bandwidth and severe noise
C. maximum bandwidth and minimum noise
D. high modulation index

3. The geostationary communication satellite APPLE is parked in the equatorial orbit at
Options
A. 102� E longitude over Sumatra
B. 90� E longitude over Bangladesh
C. 74� E longitude over India
D. 67� E longitude over Pakistan

5. In a stop-and-wait ARQ system, the transmitting terminal
Options
A. waits for positive or negative acknowled-gement from the receiving terminal after sending a block
B. sends another block if positive acknowledge is received through ACK character
C. resends the previous block if negative acknowledgement is received through a NAK character
D. does not wait for acknowledgement after sending a block

6. The Sun blots out the transmission of a geosynchronous satellite twice a year when satellite passes directly in front of it. This outage lasts for about
Options
A. 10 minutes on 5 consecutive days
B. 5 minutes on 10 consecutive days
C. 30 minutes for 5 consecutive days
D. one hour for 5 consecutive days

8. Which one of the following statements regarding compandor is FALSE?
Options
A. It compresses the higher-amplitude parts of a signal before modulation and expands them back to normal again after demodulation.
B. It gives preferential treatment to the weaker parts of the signal
C. For weaker signals it gives a poor ratio of signal strength to quantizing error
D. Weaker signals, traverse more quantum steps than they would do otherwise and so quantizing error is reduced.

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