UCL: Researchers use Wi-Fi signals to see through walls

A team of UCL researchers, assisted in commercialising their discovery by UCLB, have discovered a revolutionary new way to detect objects through walls using every-day Wi-Fi technology found in homes and businesses across the UK.

Similar to how radar works through detecting reflected radio waves, the device invented by Dr Karl Woodbridge (UCL department of Electronic and Electrical Engineering) and Dr Kevin Chetty (UCL department of Security and Crime Science) is designed to utilise these signals and enable remote location of objects through physical obstacles.

The device works through detecting the changing frequency of radio waves reflected off a moving object. Comprised of a radio receiver of two antennas and a processing unit, and about the size of a suitcase, Dr Woodbridge and Dr Chetty’s invention has been used to accurately determine a human subject’s location, speed and direction in tests. The penetration of waves emitted by wireless devices – found in a quarter of homes worldwide – means that the device can be used through walls up to one foot thick. It is also undetectable, not emitting any radiation itself.

The applications for the innovative new design range from spotting intruders to monitoring children or the elderly. Additionally, the Ministry of Defence has offered further funding to study whether it would be possible to use the device to scan buildings in closely fought urban combat situations.

“This is a significant breakthrough with all sorts of interesting applications,” says Dr Woodbridge. “With development, we could make the equipment even more sensitive; sensitive enough, perhaps, to detect the movements of someone breathing, and so whether they are standing, sitting or lying down, for example.”

Dr Vassilios Albanis, Business Manager at UCLB comments ‘the research group in collaboration with UCLB have now arranged for a prototype to be made available for a set of field trials to validate the technology. In addition, discussions with UK-based companies that operate in the radar and detection sectors are taking place to help bring this technology to the market’.