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# How Does WiFi Work?

Have you ever stopped to consider exactly how email or streaming video gets into your smartphone or tablet so quickly, seamlessly, and in real time? That's WiFi in action. This week, Tech Talker delves into the technology behind wireless devices.

By
Eric Escobar,
April 10, 2014
Episode #119

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Do you ever have that moment where you step back and think about how something you use every day actually works? More specifically have you ever wondered how the heck computers actually communicate wirelessly?

Well, that's exactly the question we're going to be tackling in today's podcast. >

## What Is WiFi?

First, let's cover some of the basics. WiFi stands for Wireless Fidelity and is the same thing as saying WLAN which stands for "Wireless Local Area Network."

WiFi works off of the same principal as other wireless devices - it uses radio frequencies to send signals between devices. The radio frequencies are completely different say from walky talkies, car radios, cell phones, and weather radios. For example your car stereo receives frequencies in Kilohertz and Megahertz range (AM and FM stations), and WiFi transmits and receives data in the Gigahertz range.

To break it down even further, Hertz (Hz) is simply a unit of frequency. Let's say you're standing on a pier watching waves come in. As you look down at the waves you can see the crest of each wave roll on by. If you counted how many seconds between each wave crest this would be the frequency of the waves. So if the time between each crest was 1 second that would meant the wave frequency was 1 hertz or one cycle per second.

Comparing sea waves to Mhz and Ghz, these waves are moving at 1 million and 1 billion cycles per second in the air! And to receive the information found in these waves, your radio receiver needs to be set to receive waves of a certain frequency.

For WiFi this frequency happens to be 2.4Ghz and 5Ghz. These waves are very similar to the frequency found in your microwave! Your microwave uses 2.450Ghz to heat up food and your router uses 2.412 GHz to 2.472 GHz to transmit your data over WiFi. This is why some people with old or faulty microwaves experience a problem with their WiFi signal when they try to make popcorn.

Just to clear up a popular misconception: These microwaves are non-ionizing radiation. That means that they do not cause cancer. That’s right kids, microwaves will not make you radioactive and glow in the dark!

## How Does WiFi Work?

I mentioned before that WiFi uses both 2.4Ghz and 5Ghz frequencies. Generally older devices only have 2.4Ghz because that was the standard before 5Ghz came out.

But whether you are in the 2.4Ghz range or the 5Ghz range, there will be a set of channels your router will communicate on. These channels are a slightly different frequency from one another and they allow multiple routers to communicate in the same area without causing a lot of traffic. Just picture yourself driving on the freeway - if there was only one lane, it would cause a traffic jam; but with multiple lanes traffic flows smoothly.

You've probably noticed that you don’t have to worry about setting channels or anything when connecting to WiFi. That's because this is usually set up automatically when you connect your router. Your computer and router will work out the details between them.

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