WiFi 101 (In plain English) -part 1/2-

..Or "How far can my wireless router reach?"

 I used to design indoor wireless coverage systems for mobile operators, and I get asked this question a LOT. The answer was always a frustratingly vague, "It depends." My goal here is to demystify that answer by looking at the three key "ingredients" at play: Your Router, The Medium it travels through, and Your Device.

 This first infographic gives a great overview of the entire system. Think of it as our map for the journey ahead.

Ingredient #1: Your Router (The Source)

 Everything starts here. Think of your router as the one doing all the talking. How well it's heard depends on a few things.

• Output Power: This is basically how loud your router is shouting. It's measured in dBm. More power means more range, but there are legal limits.


• Frequency Range: 2.4 GHz is better at punching through walls for longer range, while 5 GHz offers much faster speeds at a shorter range. You have to trade one for the other.


• Antenna Gain: A high-gain antenna is like a torch, focusing all that energy in one direction to go much further, whereas a low-gain antenna is like a bare lightbulb, spreading the signal everywhere.

Ingredient #2: The Medium (The Journey)

 Once the signal leaves the router, it has to survive a treacherous journey through your home. This is where most of the signal strength gets lost, as you can see below.

• The Distance: Even in wide-open space, the signal naturally gets weaker the farther it goes. It's just physics.


• The Obstacles: Thick walls are WiFi's natural enemy. Concrete and stone will kill your signal, while drywall and wood are much kinder. Metal reflects the signal (why elevators are dead zones), and water absorbs it.

Ingredient #3: Your Device (The Destination)

 Finally, your phone or laptop has to be able to hear what the router is shouting. Why can't Grandma hear you, while your neighbor can? She has lower sensitivity. It's the same with electronics. Your laptop, with its larger antennas, usually has a higher sensitivity than your tiny smartphone and can pick up on a much weaker signal.

 So, the final answer is a combination of all these things! For now, just know that a weak signal isn't always the router's fault.

In case you're wondering, I made these infographics using Piktochart.