US intelligence agencies, armed development specialists at University College London, have learned to “see” the movement of people who are in the next room for the opaque walls.
The movement of objects, which are equipped with radiation detectors, scientists have begun to monitor, using the Doppler frequency shift of the radiation resulting from the movement of objects in the Wi-Fi or mobile signals.
With this technology it is possible to track the movement of people behind a concrete wall up to 25 cm. Even today, so you can track the gestures of a person if he is holding a smart phone.
Secret services the new technology will be useful in the case of, for example, the terrorist threat, when you want to calculate and eliminate the intruders.
In the first half of August, the development of scientists won the award Engineering Impact Award, awarding ceremony took place in Austin (Texas, USA).
Previous track the movement of people for the opaque walls offered scientists at the Massachusetts Institute of Technology – then use the signals GSM and LTE. These radars can not only receive signals and transmit them.