Researchers at University College London (UCL) have devised a system for detecting the Doppler shifts of ubiquitous Wi-Fi and mobile telephone signals to “see” people moving, even behind masonry walls 25 centimeters thick. 
The method, which could be useful in situations from hostage-takings to traffic control, won the 
Engineering Impact Award in the 
RF and Communications category at this National Instrument’s NI Week 2015 meeting (which convened in Austin, Tex., 3-9 August). 
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