You just need to write it smaller than the Wi-Fi wavelength (about 60 nm) and you should be fine. If someone wants to read it, they have to use smaller wavelengths (i.e. higher frequencies), which means there’s a good chance that they will be blocked by your walls.
Edit: c/2.4 GHz ≈ 125 mm
I took the first value from Wikipedia, without thinking about it enough.
It’s all about the size. You can’t use an optical microscope to look at details smaller than the wavelength of visible light. You need an electron microscope for that. Similarly, a wifi camera can’t see details smaller that the wavelength.
If you made a camera that can see in 100 MHz radio waves, you could probably see mountains, rivers and houses, but anything smaller than 3 m would be nothing but blur.
27 Comments
JazzAlien@lemm.ee · 54 pts · 2y
The tech to scan objects in a room using WiFi is not new. It's very unsettling.
Metal_Zealot@lemmy.ml · 43 pts · 2y
I spy, with my little wifi...
Wussy@lemmy.world · 32 pts · 2y
And here I am thinking that hanging my passwords on the wall as art was hack proof. I guess it's time to redecorate.
Hamartiogonic@sopuli.xyz · 7 pts · 2y
You just need to write it smaller than the Wi-Fi wavelength (
about 60 nm) and you should be fine. If someone wants to read it, they have to use smaller wavelengths (i.e. higher frequencies), which means there’s a good chance that they will be blocked by your walls.Edit: c/2.4 GHz ≈ 125 mm I took the first value from Wikipedia, without thinking about it enough.
crapwittyname@lemm.ee · 6 pts · 2y
I think your fag packet calculation has got a power of ten wrong somewhere. Wi-fi is GHz so that would be on the order of centimetres I think.
Turun@feddit.de · 4 pts · 2y
Yes. Wifi is 2.4 GHz, speed of light is 0.3 Gm/s. Therefore one wavelength is 0.3/2.4 m/s/Hz = 12.5 cm
crapwittyname@lemm.ee · 2 pts · 2y
Or 0.001 football pitches
Hamartiogonic@sopuli.xyz · 1 pts · 2y
Yeah, you’re right. Writing it smaller than 12.5 cm should do it, which is entirely reasonable.
Wussy@lemmy.world · 2 pts · 2y
What if I use an awesome font like Comic Sans and round the faces like party balloons? Still visible?
Hamartiogonic@sopuli.xyz · 1 pts · 2y
It’s all about the size. You can’t use an optical microscope to look at details smaller than the wavelength of visible light. You need an electron microscope for that. Similarly, a wifi camera can’t see details smaller that the wavelength.
If you made a camera that can see in 100 MHz radio waves, you could probably see mountains, rivers and houses, but anything smaller than 3 m would be nothing but blur.
PeleSpirit@lemmy.world · 25 pts · 2y
TheMauveAvenger@lemmy.world · 19 pts · 2y
If we're seeing it now, the government has probably been using it for years.
dot20@lemmy.world · 9 pts · 2y
https://nij.ojp.gov/library/publications/through-wall-sensors-law-enforcement-market-survey
thesmokingman@programming.dev · 11 pts · 2y
This is vaguely similar to Van Eck phreaking.
finthechat@kbin.social · 10 pts · 2y
Lucius Fox hates this
planish@sh.itjust.works · 9 pts · 2y
Nioxic@lemmy.dbzer0.com · 7 pts · 2y
This is super creepy
AlecSadler@sh.itjust.works · 6 pts · 2y
Are there ways to design a room or things to put in a room (or the walls?) that would inhibit this ability?
I suppose lead shields or something...
Sotuanduso@lemm.ee · 21 pts · 2y
No need. If you skim the article, you'll see it only works on sharp edges. The letters being read here are metal cutouts.
ComfortablyGlum@sh.itjust.works · 9 pts · 2y
Note to self: "decorate with crystal balls..." Got it!
Devjavu@lemmy.dbzer0.com · 5 pts · 2y
Lemmy is so damn salty. All you did was explain what was said in the article and some guy disliked your comment lmao
Sotuanduso@lemm.ee · 3 pts · 2y
Yeah, but it was only one person. No big deal.
Devjavu@lemmy.dbzer0.com · 1 pts · 2y
There he iiiiis
big_slap@lemmy.world · 1 pts · 2y
there's always that one person, lol
Deceptichum@kbin.social · 8 pts · 2y
Faraday cage?
shininghero@kbin.social · 4 pts · 2y
No need for lead. Just make something similar to those microwave door mesh plates and embed it in with the insulation.
fishos@lemmy.world · 0 pts · 2y
Well, if it's using WiFi, then anything you do will also kill your WiFi signal. So, bare minimum, no WiFi router, only LAN lines.
EdibleFriend@lemmy.world · 3 pts · 2y
Yeah sure why not.
roguetrick@kbin.social · 1 pts · 2y