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4.1
Propagation of radio waves
4.1.1
Basics
Wireless technology is based on the propagation and receipt of electromagnetic waves.
These waves are not subject to wear of any kind, but respond in very different ways in terms
of propagation, dispersion, diffraction, and reflection depending on their frequency. The
propagation of waves in an area is three-dimensional and occurs at different strengths.
Numerous factors affect this propagation, however none of these factors may affect the
propagation to the extent that a signal is not safely detected at the recipient.
4.1.2
Propagation of radio waves outdoors
(Fresnel zone)
Keep Fresnel zone free from any obstacles.
Figure 4-1
The Fresnel zone