Radar Engineering and Satellite Communication MCQs

Question 1

Which one of the following statement is correct?

Accepted Answer

the width of a beam in space is inversely proportional to the width of the transmitting antenna

Answer

satellite spacing is not affected by the bandwidth of the transmitting Earth station

Answer

beam-width in independent of antenna size and frequency band used

Answer

use of high-frequency bands permits less number of satellites to share the orbit

Question 2

In communication satellites, the up-link normally operates at a higher frequency than the down-link because

Accepted Answer

it gives a narrow - beam shining into space

Answer

results in lesser signal attenuation

Answer

gives better beam-shaping

Answer

iseasier to polarize a high frequency beam

Question 3

As compared to 17.340 antenna, the total increase in the signal relayed by 4.5? antenna of INTELSAT-IV is

Accepted Answer

220

Answer

14.85

Answer

78

Answer

3.85

Question 4

Power received from Sun per m2 surface area of a geosynchronous satellite is nearly watt

Accepted Answer

1000

Answer

100

Answer

500

Answer

2000

Question 5

The degradation of satellite solar cells with time is mainly due to

Accepted Answer

their bombardment by electrons

Answer

collection of meteoric dust

Answer

increase in resistivity of silicon

Answer

gradual leakage of charge carriers from the semiconductor material

Question 6

Nutation of a geosynchronous satellite means its

Accepted Answer

three-axis stabilization

Answer

drift from stationary position

Answer

wobbling

Answer

three-dimensional stabilization

Question 7

When a communication satellite passes into Earth's shadow, its temperature drops to about oK

Accepted Answer

123

Answer

273

Answer

243

Answer

170

Question 8

A typical signal strength received from a geosynchronous communication satellite is of the order of a few

Accepted Answer

watts

Answer

milliwatts

Answer

kilowatts

Answer

picowatts

Question 9

A certain sound has 10,000 times more energy than another sound. The number of times it would sound stronger to a listen& is

Accepted Answer

40

Answer

10,000

Answer

100

Answer

10