As if 2017 hasn’t already given us enough to be ordained The Most Stressful Year Ever. Donald Trump is president, there are terrorist attacks happening all the time, the job market sucks, finding an affordable place to live is almost impossible, everyone and their dog is hacking into everyone and everyone else’s dogs’ personal information, Net Neutrality is being threatened again, and WannaCry makes owning a computer feel like you own a time a bomb. Are you triggered yet? Well buckle up your thrift shop boots and strap into your DIY chair, because the days of “privacy” in your own home are speeding towards their retirement at light speed. Not only can a Wi-Fi enable others to snoop communications and online activity, but soon, thanks to some research coming out of Germany, it will effectively enable people to see what’s going on inside the walls of your home–no webcam necessary.
As we all know, internet routers send out a Wi-Fi signal that bounces off and goes through the walls of a room to reach a receiver such as a phone, tablet, or laptop. This signal is like a beacon trying to find anything and everything that will respond. Before, the Wi-Fi signal was just innocently bouncing around our houses. Now, there is a device that will translate the aggregated path of a Wi-Fi signal into a 3D hologram of the inside of a room. “It can basically scan a room with someone’s Wi-Fi transmission,” said Philipp Holl, an undergraduate physics student at the Technical University of Munich.
Holl initially built this device as part of his bachelor thesis, along with his academic supervisor Friedemann Reinhard, and then submitted their study to the scientific journal, Physical Review Letters. Currently, this particular technology is only in its prototype stage and has limited resolution, but the ability to see through walls using a Wi-Fi signal has actually been around for years. Some home security systems can detect intruders or track a moving object with a couple of Wi-Fi antennas. But this is the first instance where someone was able to make a 3D hologram of the inside of an entire room, as well as the objects inside.
To properly scan a room, the device needs two antennas: one that moves, and another fixed in place. Both antennae are scanning for the Wi-Fi emitter, the moving antenna doing it from multiple points. The antennae then record the intensity and the phase of the Wi-Fi signal–because the signal travels in waves, it is easier to track. Finally, both antennae collect the data into a computer, where the software slowly builds a 3D hologram by stacking a bunch of 2D images from the inside of the room on top of each other.
Again, this process is still in the prototype stage, so the images are still blurry. Holl hopes that this device will be later used for helping rescue workers find people lost under collapses; however, nobody will be surprised when this starts getting used to facilitate far less altruistic ambitions.
