No, really. You can see through walls using drones and Wi-Fi Drones can perform three-dimensional imaging of objects through walls using Wi-Fi, a team of researchers demonstrated for the first time. Chitra Karanam, a PhD student, and Yasamin Mostofi, a professor at the department of electrical and computer engineering at the University of California, Santa Barbara, presented their …
...for the majority of users there is no chance in hell of them penetrating their dwelling.
Two points concerning this: 1) the signal strength needed to form an image is not necessarily the same as that needed to create a usable image and 2) passive scanning might be more effective as most houses and businesses have wi-fi of some sort running all the time. In fact, passive scanning has the potential for clearer images in some cases as it has to go through, on average, half of what an active system would.
I'd rather have that meta-material cape that can bend microwave around me invisibly. You got any? Come on, just because your couture of choice is tin foil-based doesn't mean you don't have to keep track of what's in vogue this year...
Wifi isn't a particularly good radar frequency for imaging houses. 2-3GHz is used in aicraft surveillance typically, 5GHz for weather mapping. Better for range (at markedly higher power than typical domestic wifi equipment, obviously), less good for resolution. You want much higher frequencies in the 20GHz+ ranges really for decent resolution at ranges like that. Your car parking radar sensors are circa 75GHz to give you an accurate idea of how close you are to that car behind you.
More on this sort of stuff at radartutorial.eu
I suspect that "proper" radar kit is expensive whereas WiFi kit is everywhere - and you may not even detect that you're being scanned.
Personally, I would like to thank the University for giving me yet another reason to down a drone as soon as it comes near my property. And get a WiFi jammer.
Those higher frequencies will give you the extra resolution, but only if they can actually pass through the brick walls. (Ironically, this probably means that conventional radar wisdom is mis-leading because conventional radar depends on the opacity (or at least, the reflectivity) of materials to the chosen wavelength, not their transparency as required here.)
...a lot of problems have to be solved before drones can be used for more complex situations like search-and-rescue operations, structural modelling to monitor the state of buildings and bridges, or inspecting potential archaeological sites.
The above sound like good uses for this technology if it works. But it could also be used for spying on people in their homes. Of course, who would want to do a thing like that?
Might be an idea to keep a loaded shotgun (or other drone-stopping device of your choice) handy.
Calling it "wifi" sounds lovely and headline grabby, but it's just using a radio frequency in the wifi range. It may have well said "microwave oven drone".
Or, all they've done is stick some GPR equipment on a drone. Interestingly, GPR already uses frequencies either side of the wifi range.
https://en.wikipedia.org/wiki/Ground-penetrating_radar
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