Question: How does WiFi work

Gary Munnelly answered on 5 Nov 2018: last edited 5 Nov 2018 3:45 pm

Oooh! I like this question! There is a short answer and a long answer.

The short answer is that WiFi works by making particles in the air vibrate at very specific speeds. WiFi receivers can pick up on these vibrations and decode them. What you get after decoding the vibrations is data that could be a YouTube video, or a web page or a Snapchat message, or something else.

Now the long answer. The scientific word for “vibrating” is “oscillating”. Oscillating basically means that a particle is moving quickly between two points. If you were to run between two goal posts over and over, it could be said that you are oscillating (very, very slowly relative to most other particles).

Depending on how fast particles oscillate, we get different types of waves in the air. Humans can physically hear particles that oscillate between 20 and 20,000 Hertz (that means you can hear particles which vibrate somewhere between 20 and 20,000 times per second). The human voice causes vibrations in the air that oscillate at about 85 to 180 Hertz. Your ear picks up on these vibrations and decodes them as words, sounds, songs etc.

If we make things bounce a little faster, we get radio waves that you can pick up in on your stereo. Those waves are oscillating at around 30,000 – 300,000 Hz (if you’re listening to AM radio. FM is way faster). This is much too fast for you to hear, but the arial on your stereo can detect them and translates them to sounds you can hear.

Now if we go even faster! Particles oscillating at 30,000,000,000 – 300,000,000,000 Hertz gives us WiFi. Just like the arial on your stereo, your phone or computer has an arial built in that can detect and decode these waves and also emit them in a manner that lets you download data.

So you can think of WiFi as being a bit like someone shouting information across a room at a frequency that you can’t hear. If things are in the way, then it can be a little harder to hear. If loads of things are shouting at the same time, then it gets hard to hear the voice you want to listen to.