A radio wave is traveling away from an antenna at an initial angle of 45 degrees
ID: 2001882 • Letter: A
Question
A radio wave is traveling away from an antenna at an initial angle of 45 degrees above the horizon.
a) Assuming that the velocity of electromagnetic radiation in the layer of atmosphere closest tothe earth’s surface is 2.83×108 m/s, what does the radio wave’s angle of travel above the horizon becomewhen it passes into an atmospheric layer where the EM velocity is 2.97×108 m/s?
b) What wave property describes this behavior and what is the resulting impact on transmission range of the radio signal?
Explanation / Answer
a) The change of speed is due the refractive index of two part of the atmosphere.
b) The wave property is scattering and diffracction, and to produce significantly different path losses for equal distances.