Satellite Communication

Question 1

What are microwaves sent into space from?

Answer 1

Parabolic transmitter

Question 2

What are signals received by?

Answer 2

Parabolic receiver

Question 3

Why are digital signals used for satellite communications?

Answer 3

• Don’t attenuate as quickly

- Less noise

Question 4

What does the ionosphere reflect?

Answer 4

Radio waves with frequencies below 30MHz

Question 5

What happens to signals above 30GHz?

Answer 5

Absorbed and scattered, reducing signal strength

Question 6

Why does the geostationary satellite dish and the receiver dish need to be in exact alignment?

Answer 6

The size of the geostationary satellite dish is many times the microwave wavelength so there is little diffraction. It produces a narrow beam which doesn’t spread out so the receiver needs to be in exact alignment so they signal doesn’t miss the geostationary satellite.

Question 7

What do radio waves do around buildings, the Earth’s curvature and hills?

Answer 7

Diffract because they have long wavelengths in comparison.