How to Hunt Down Wi-Fi Devices with a Directional Antenna

If you've ever wanted to track down the source of a Wi-Fi transmission, doing so can be relatively easy with the right equipment.

Using a directional Wi-Fi antenna and Wireshark, we can create a display filter to target any device in range to plot the signal strength on a graph. By sweeping the antenna back and forth, we can easily discover which direction the signal is coming from by looking for spikes in signal strength on the graph.

Uses for Wi-Fi Signal Hunting

If you've ever seen a Wi-Fi network that doesn't belong, you might wonder if there is a way to track down where it's coming from. It could be a suspicious rogue access point that appears at your place of work, a new network with a strong signal that shows up at your home, or a Wi-Fi hotspot from a smartphone that seems unusually close and strong.

Whatever it is, signal hunting can help you locate Wi-Fi client devices, meaning you can use it to track down the location of rogue devices that suddenly appear on your WI-Fi network.

The tracking of radio signals isn't new, but for a beginner looking to localize the source of a Wi-Fi network, the options may at first seem limited. By walking around with a device that can display the signal strength, like a smartphone, it's possible to observe when you get further and closer to a targeted broadcast. However, it can be pretty inaccurate due to the way Wi-Fi bounces off walls and other obstacles.

The problem with that approach is that it uses an devices directional antenna