Machine-translated by Google. Questions are authored in English.
Top

Discussion

What is ducting in tropospheric propagation?

  • A.A tunnel of low pressure air that absorbs the signal along the path
  • B.The channelling of a wave along a valley between two ranges of hills
  • C.The guiding of a signal along a metal structure such as a pipeline
  • D.A layer that traps the wave and carries it far beyond the horizon

Answer: D

A strong temperature inversion or a sharp humidity gradient can create a layer in which the wave is refracted back downward repeatedly, so it travels hundreds of kilometres with little loss. It produces both unexpectedly good reception and unexpected interference, particularly over water. Absorption, terrain channelling and conducted propagation are different phenomena. An atmospheric layer behaving as a waveguide is a striking illustration of refraction carried to its extreme.

No comment is present. Be the first to comment.
Loading…

Post your comment

Please log in or register to post a comment.