Make Wi-Fi Visible #5 – Radio Frequency Scattering

As we all know, Wi-Fi is amazing. The only thing is… it’s invisible.

So let’s start by explaining what makes Wi-Fi invisible? Wi-Fi uses radio frequencies electromagnetic waves to transfer information. These waves have wavelengths that are not within the visible space.

Light is also an electromagnetic wave. However, its wavelength is within the visible spectrum (between 330 nm and 700 nm). This is what make the light visible to the human eye. In fact, any electromagntic radiation having a wavelength between 330 nm and 700 nm is called “light” or to be precise “visible light”.

This means that we can explain Wi-Fi concepts using light analogies. In this set of articles, that is what we are going to do using simple drawings.

Episode #5 – Radio Frequency Scattering

Radio waves are sometimes scattered. It happens when the diffusion of the signal is reflected in multiples directions when hitting an uneven surface. It could be the sunlight going through a cloud or a radio wave hitting a rain drop.
Scattering is illustrated below:

If we think of sunlight going through multiple clouds, some clouds will be thicker and some others will be thinner. The light will be scattered since it will be reflected unevenly as illustrated below:

As a Wi-Fi professional, it important to remember that as the scattering of a signal continues to occur, the signal will lose its integrity and eventually die off. Scattering could happen indoor if you have a lot of inside trees. It could also happen on outdoor Wi-Fi bridges while raining as the signal hits rain drops.

Written by François Vergès

“Episode #1 – Radio Frequency Propagation” is still available!
“Episode #2 – Radio Frequency Reflection” is still available!
“Episode #3 – Radio Frequency Refraction” is still available!
“Episode #4 – Radio Frequency Diffraction” is still available!
“Episode #6 – Radio Frequency Absorption” coming next!

Leave a Reply

Your email address will not be published. Required fields are marked *