Home » Uncategorized » Detector Can Use Wi-Fi Signals to Literally See Through Walls

Detector Can Use Wi-Fi Signals to Literally See Through Walls

Your ads will be inserted here by

Easy Plugin for AdSense.

Please go to the plugin admin page to
Paste your ad code OR
Suppress this ad slot.

It’s not quite as advanced as Superman’s X-ray vision, but this newest innovation from the world of science is particularly noteworthy, because it makes use of pre-existing Wi-Fi networks. The new detector was created by Karl Woodbridge and Kevin Chetty of University College London and it taps into the Wi-Fi signal that is emitting from a regular old wireless router.

Have a look at the image above and follow along. You have a group of police officers who need to go and rescue a hostage, but they can’t see past that wall. The moving object (1) is the bad guy and because he’s moving, he’s creating a Doppler effect with the Wi-Fi signal coming from the office router (2). Remember that the radio waves compress if an object moves toward the source of the Wi-Fi signal and they “expand” if an object moves away from the source of the signal. This is fundamentally the same way that radar works, except they’re tapping into the existing wireless network.

The detecting device has two antennas. The first (3) is used to establish a baseline radio signal inside of the room beyond the wall. The second (4) is used to detect the “shifted” signal that results from the Doppler effect of the moving object. This changes the frequency of the radio wave and by comparing the signals from the two antennas, the device is able to calculate the bad guy’s location (5) within a few feet. It can even figure out speed and direction.

This is still very much in the early stages of development, but the UK Ministry of Defence is funding more research in the area that could one day have devices that can scan buildings during urban warfare, getting so precise that they can “pick up on the subtle motions the ribcage makes during breathing, which would allow the radar to detect people who are standing or sitting still.”


About Michael Kwan

A freelance writer and tech geek from Vancouver. Find me at michaelkwan.com and follow me on Twitter @michaelkwan.

Check Also


Try Oculus Rift And Wii To Roam Around On The Back To The Future Hoverboard

Check out how you can fly in virtual space by using an Oculus Rift and a Wii Balance Board.


Amazon Appstore for Android Holiday Deals, Including Free Apps

There are tons of deals from the Amazon Appstore that will be offered starting now and throughout the holiday shopping season. They say that they will have "hundreds of titles that are eitehr free... or available between 50-90% off" the regular price.


Black Friday: Google Play Store Apps, Games and Content on Sale All Weekend

Case in point, if you head over to the Google Play Store right now, you'll find that Google is celebrating all Cyber Weekend with discounts on all sorts of content. This includes many popular apps and games


Black Friday Deal: Samsung Galaxy Tab 3 10.1-Inch for $100 Off

Your ads will be inserted here byEasy Plugin for AdSense.Please go to the plugin admin ...


Arduino Co-Creator Releases Plans for $200 DIY Mobile Phone

Mellis was one of the people who came up with the now hugely popular Arduino platform and now he has come up with plans for people to build their own cell phone for about $200 in parts.


No Discounts for Apple Black Friday, Just Free Gift Cards

If you were hoping to save yourself some cash as you brave the Black Friday shopping crowds, you'll want to go somewhere other than the official Apple Stores.