Police officers serving a warrant or searching for a suspect hiding inside a building could soon have a new tool for protecting themselves and finding the bad guy.
A prototype device called the RADAR Flashlight, developed at the Georgia Tech Research Institute (GTRI), is said to detect the presence of a human through doors and walls up to 8 inches thick.
The device uses a narrow 16-degree radar beam and specialised signal processor to discern respiration and/or movement up to three meters behind a wall. The device can also penetrate heavy clothing to detect respiration and movements of as little as a few millimetres.
‘We believe the RADAR Flashlight potentially will be useful to police officers in ambush situations,’ said Gene Greneker, the GTRI principal research scientist who led the development of the device.
The RADAR Flashlight is undergoing further modification and testing for the next six months. The Georgia Institute of Technology has filed a provisional patent for the device, which could become commercially available to law enforcement officials within a couple of years if the university licenses the technology to a manufacturer.
‘We will be modifying the RADAR Flashlight based on what law enforcement officials told us from the tests,’ said Greneker. ‘For one thing, they said it makes too much noise when it locks onto a wall (to scan). Also, for use by SWAT teams, the RADAR Flashlight needs to be operated by remote control. So we plan to put the RADAR Flashlight on a tripod at least 25 feet away from a wall and steer it by remote control to the part of the wall we’re interested in scanning.’ In its current form, the RADAR Flashlight operates in the following manner: The user holds the device with a pistol-grip handle, pulls a trigger, and the device runs a 3-second self-test to verify that it is properly functioning.
The user sees the results as a bar graph on a small LED display built into the device. Then the user presses the device against a wall, pulls the trigger and within 3 seconds the system automatically spaces itself from the wall at a distance designed for best performance.
The RADAR Flashlight’s narrow radar beam sends out a pulse of electromagnetic energy, then detects the return signal, which is read by high-speed signal processing technology that quickly delivers bar-graph results to the user’s display. As the person on the other side of the wall breathes, the bar-graph display rises and falls with a rhythmic response.
The device does, however, have a self-defeating flaw.
‘We have one problem,’ Greneker says. ‘This instrument is so sensitive to motion that if you don’t hold it still enough, it will detect its own self-motion. If we can overcome this, it would be the Holy Grail, and interestingly enough, we think we know how to solve this problem with additional research.’