Seeing through walls with WiFi signals and USRP software defined radios

Researchers at the University College of London have found a way to use WiFi signals to see through walls, using a USRP software defined radio and software written in LabView. The researchers have shown that they are able to utilize local WiFi signals to detect and monitor moving objects such as people behind a wall in a similar fashion to how radar systems work. The advantage over traditional radar is that their system is completely passive, requiring no transmitter, other than the already ubiquitous WiFi signal.

In a demonstration the researchers showed how they were able to not only detect the presence of a person behind a wall, but also detect small hand gestures that were made.

Detecting body gestures from WiFi signals in LabView.
Detecting body gestures from WiFi signals in LabView.

It appears the researchers are patenting their work and are looking to market their technology towards military and security surveillance operators as well as towards other applications such as traffic monitoring and the monitoring of children and the elderly.

We aren’t sure what type of radio accuracy is required for a system such as this, but it may be possible that SDR’s that cost less than the USRP may also work, assuming the software technology can ever be replicated/licensed.

A proposed application of the technology: Allowing police to see through walls in a hostage situation.
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also i really wish other websites would allow anyone to post,

and i would like to thank sdr for doing that.

there were so many times that i wanted to say something i thought was really useful or important,

but alas!


this is really creepy because now anyone would now be able to see everything through any walls.

even through the walls of the skull.

Edward SDR man

Are you saying that Mr Bo Tan is the:

“NI Engineering impact awards: RF & communications winner”

sponsored by: Yes you guessed it NI.

I thought this exact same research was conducted by UCLA at least a year ago.

What’s with the ridiculous patent approach on such an infant technology…

Ever seen a carcass floating face down in a river…

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