Question

In satellite communication, Faraday rotation is caused by 
1. Plasma frequency
2. Earth’s magnetic field
3. Non-Gaussian nature of uplink noise when received in the downlink channel
4. Ionospheric reflections that occur multiple times

Answer 1

Correct Answer - Option 2 : Earth’s magnetic field

Explanation:

Faraday effect or Faraday rotation is a magneto-optical phenomenon – that is an interaction between the light and magnetic field in a medium.

• Radio waves passing through the Earth’s ionosphere are subjected to the Faraday effect, the ionosphere consists of a plasma containing free electrons which contribute to Faraday rotation.
• In conjunction with the earth’s magnetic field rotation of the polarization of radio waves occurs.
• However, the Faraday effect due to free electrons diminishes rapidly at higher frequencies.