3D Imaging through Walls

One thing that Joyce Gioia our author loved about being in Seoul was the presence of free Wi-Fi almost everywhere. Chances are, the fact that South Korea is the most wired country in the world had a lot to do with it.

Soon Wi-Fi will be everywhere

Wi-Fi is already almost everywhere. Imagine being able to focus Wi-Fi signals to create holograms? It sounds like science fiction, but that is just what two German researchers could accomplish. They have developed a method to use Wi-Fi signals to create 3D holographic images of objects around a network. They could even capture these images, even through solid materials, including doors and walls.

How the technology works

The technology works by recording the shapes made by errant radiation from the electromagnetic waves that bounce off of objects, as they travel through the air. Acting like a low-powered radar scanner, the method uses Wi-Fi signals to scan a room. Transmitting devices, like our phones and other electronic devices, are harnessed to act as a light source for the imaging system, which depends on two antennas.  One scanner maps a 2D plane, while the other records the signal. Once the image data is collected, the three-dimensional views of objects are put together into a digital reconstruction algorithm, which creates the holographic map of objects within the space. The more antennae doing the scanning, the faster and more accurate system could be. 

It started as an undergraduate thesis

The fascinating research behind this 3D-imaging method, started as an undergraduate thesis. Later the project was expanded into a larger study, and was first published in the Physical Review of Letters earlier this month. This remarkable technique can recreate the contents of an entire building in a large-scale simulation. Wow!  

Not new, but a definite breakthrough 

Using Wi-Fi for imaging, by itself, is not new.  However, the researchers claim that this breakthrough is the first time Wi-Fi signals have been used to produce 3D holographic representations of large spaces.

Not very detailed---for now

For now, the system isn't accurate enough to discriminate many details, but it does identify shapes and figures within the space---in fact, any object that's more than four centimeters.

Privacy issues in our future

Not surprisingly, this technology brings up significant privacy issues; and as the technology advances, these issues will become more critical. As a society, we will have to confront the importance of public safety versus personal privacy.