Communication Systems – Solutions

1) Which of the following frequency/frequencies will be suitable for communication beyond the horizon using sky waves?

(a) 10 kHz  (b) 10 MHz   (c) 1 GHz  (d) 1000 GHz

Solution:

Correct answer is (b).

Large antennas cannot radiate 10 kHz, while 1 GHz and 1000 GHz will penetrate them. Hence, 10 MHz is suitable for communication beyond the horizon using sky waves.

2) Frequencies in the UHF range normally propagate by means of:

(a) Ground waves (b) sky waves (c) surface waves (d) space waves

Solution:

Correct answer is (d).