How far can a wi-fi signal travel?

Quick answer: further than you can imagine.

We’re often frustrated when our wi-fi doesn’t travel all the way from one end of the house to the other. We swear under our breath when it doesn’t go into the meeting room we’re about to enter. Yet, there is no reason that a wi-fi signal can’t travel miles, or hundreds of miles with the right equipment.

Wi-fi is just a radio transmission. Radio transmissions come thousands of light-years from space. There are two limitations to any form of transmission: broadcast power and obstruction. Wireless routers tend to use a very small amount of broadcast power, along the lines of a nightlight bulb. This is on purpose: wi-fi is designed to stay in smaller areas, so the same frequencies can be shared with millions of people and none of the signals interfere.

Up the power, or redesign the antenna, and you can get a huge difference in coverage. You have to be careful not to run afoul of the rules, though. An antenna like the one you see above can help you reach every area of your home or business while you’re operating your router at the maximum allowed power.

The other issue with any sort of radio signal is of course obstructions. Radio signals travel from faraway galaxies with nothing between them and us, through almost empty space. On the other hand, your wi-fi router has to go through walls full of wiring and possibly even metal studs. RF signals travel well through walls but nowhere near as well as they do through open space.

In the coming weeks, we’ll be showing you ways to build wi-fi networks that can serve even the largest spaces!