Earthquakes, tornados, hurricanes, and other extreme weather events cause immense destruction: Buildings crumble, houses turn to rubble, animals, and people are buried in the wreckage.
In the immediate aftermath of such destruction, first responders desperately search for any sign of life in what used to be an office or home. Unfortunately, they frequently end up digging in the wrong pile of rubble, wasting precious time. If rescuers could see through the debris to instantly spot survivors under the rubble, measure their vital signs and even generate images of the victims, it could save many lives. This is becoming possible, thanks to see-through-wall radar technology.
New Radar System
Researchers at the U.S. National Institute of Standards and Technology (NIST) have developed a new radar system that relies on microwaves with longer wavelengths to pass through solid objects like walls or floors. This unique radar system can produce accurate real-time images and video of what’s behind them, even when things are moving at hypersonic speeds!
Fabio da Silva, a researcher who led the project at NIST, explained:
“Obviously, I cannot see through those walls because the kinds of wavelengths that the human eye is sensitive to, they don’t penetrate such objects very well. However, if you go to longer wavelengths, like in the microwave regime – you should be able to ‘see’ through the walls.”
The NIST researchers published their findings on June 25 in the journal Nature Communications.
Radar Technology
See-through-wall technology was initially conceived during the Cold War to replace drilling ‘spy’ holes through walls. There are a few commercial products currently on the market, like Range-R radars used by law enforcement officers to track motion behind walls. According to their manufacturers, other radar devices such as RadarVision2 include three-dimensional displays of where people are located inside a building.
Traditional radar technology sends radio waves to a site via a transmitter. Those waves bounce off of an object in that area and are detected by a receiver. Thus, one can determine the location, size, and movement of things on the site using the data gathered by those “radar echoes.” Typically, this method involves multiple receivers and fewer transmitters.
Microwave Technology
On the contrary, NIST’s system works by sending out microwaves —the waves themselves, not the appliance— via multiple transmitters and only one powerful and sensitive receiver. The system also relies on light waves that bounce off other objects as it makes its way back to the receiver, allowing it to more quickly and accurately determine what is in a specific location. “You use the idea that light bounces off other objects and these objects then illuminate other objects from multiple bounces,” explained da Silva.
Microwaves are the shortest members of the radio wave family. Their wavelengths range from the thickness of a dime to the size of a school ruler. But, did you know – they’re already used in radar technology; the devices that track a car’s speed on the highway rely on microwaves too!
Massive Potential
While this incredible technology is still in its beginning stages, it has vast potential! For example, seeing through solid objects can assist first responders in search and rescue efforts – from locating people trapped in burning buildings to searching for survivors after an earthquake. It can also detect objects through extreme weather events such as hail, rain, and clouds.
NIST scientists claim that the new system can detect and track objects moving at hypersonic speeds, including adversarial planes, missiles, and even space junk that might prove deadly to humans and wildlife on the ground.
The U.S. Army has made it clear that it wants cutting-edge technology that can see through walls. Last year, the Army uploaded a request for information to identify commercially available technologies that could accelerate the development of “see through the wall systems” and state-of-the-art technologies that enable soldiers to be more efficient, effective, and lethal.
