Question
Explain ground wave propagation
✓
Answer
- When a radio wave from a transmitting antenna propagates near surface of the Earth so as to reach the receiving antenna, the wave propagation is called ground wave or surface wave propagation.
- In this mode, radio waves travel close to the surface of the Earth and move along its curved surface from transmitter to receiver.
- The radio waves induce currents in the ground and lose their energy by absorption. Therefore, the signal cannot be transmitted over large distances.
- Radio waves having frequency less than 2 MHz (in the medium frequency band) are transmitted by ground wave propagation.
- This is suitable for local broadcasting only. For TV or FM signals (very high frequency), ground wave propagation cannot be used.
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