New radar can detect concealed weapons
Kaitlin ZurdoskyMay 6th, 2013
While politicians debate gun-control laws, Electrical Engineering prof. Kamal Sarabandi and colleagues have been developing a different type of solution for weapons abuse.
The team’s new radar system has the ability to detect concealed weapons hidden underneath clothing, which can help law enforcement officers in anticipating potential attacks.
Sarabandi said the radar system works by sending a calibrated radar signal at a certain polarization — a reflection of light — on a smooth surface, to detect a person’s skin. The signal is sent out and most of the signal gets reflected off of skin back to the radar. When the signal hits metal, it reflects back with a change in polarization. This will notify the system that there is something hidden underneath clothing.
Sarabandi has been working on the project for about five years. It wasn’t originally intended for detection of weapons, but the Engineering department has now received grants from the Department of Defense.
“We are working on the next generation of these radars that can be utilized for the detection of explosives,” Sarabandi said. “The technology is very promising in the sense that the radar is smaller than your credit card.”
Once the system is refined, it will have the potential to be installed in locations such as airports, school buildings and other public locations. The next step in the process involves engineers testing the system in different environments.
Engineering student Mehrnoosh Vahidpour said the current technology, which Sarabandi’s radar would replace, isn’t ideal for crowded places such as stadiums.
“The current systems for surveillance require close proximity to the subject and radiometric calibration,” Vahidpour said. “Their processing is slow, and since they are mainly imaging radars, they give low-quality blurred images in heavily cluttered environments.”
Placing the new radar system in public locations has virtually no disadvantage to the public, Sarabandi said. A benefit of the system, as compared to airport scanners, is that no image is produced, ensuring violations of privacy aren’t an issue.
The signals sent out of this radar system cause very little harm to the human body, Sarabandi said. Unlike ionizing radiation — such as X-rays — that can harm the body, the new radar doesn’t penetrate more than .1 millimeters into the skin.
Additionally, the radar hones in on the torso area of the body, where weapons are most likely to be concealed, by analyzing body movements.
“Human motion has a unique pattern. The response of human-like targets are mostly co-polarized, therefore the response of any irregular objects (like handguns) which shows a high cross-polarized response can be isolated from the human body's response,” Vahidpour said.
The system has the capacity to send out signals at far ranges. When detecting foreign objects against a person’s body, the signal virtually filters through clothing. Clothing does not produce much backscatter, or reflected electromagnetic waves, as a metal object does. In this way, the radar is able to detect a concealed weapon as opposed to other material objects against the skin from far distances.
Although there are years of work to be done and hundreds of more stages involved, the engineers hope to get the system working in the general public soon.
“Engineering is an exciting field, and it can make changes in peoples’ lives,” Sarabandi said. “It can really contribute to society.”
Printed from www.michigandaily.com on Tue, 28 May 2013 03:17:56 -0400