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When microwave signals follow the curvature of the earth, this is known as -

When microwave signals follow the curvature of the earth, this is known as - Correct Answer Ducting

  • Atmospheric ducts are caused by the low refractive index of the lower atmosphere. They significantly alter the near‐surface wave propagation by trapping propagating signals.
  • In this way, atmospheric ducts behave like a waveguide, and trapped signals can even propagate more than 1000 km in the ducting layer. Therefore, communication and radar systems can be adversely affected by the presence of atmospheric ducts.

 

The duct propagation is explained with the help of the following diagram:

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