3 ms·

I know nothing about this issue: I had to look up https://en.wikipedia.org/wiki/Extremely_high_frequency https://en.wikipedia.org/wiki/Extremely_high_frequency

I know nothing about this issue: I had to look up https://en.wikipedia.org/wiki/Extremely_high_frequency https://en.wikipedia.org/wiki/Extremely_high_frequency to learn what mm-wave electromagnetic radiation is. Other than attenuation caused by rain-drop scattering and atmospheric absorption, I couldn’t find much information about the downsides of using EHF EMR in the context of cell networks. Can you recommend any good summaries of developments in this area and its associated risks (privacy or otherwise)?

webmaven 5y ago
> Can you recommend any good summaries of developments in this area and its associated risks (privacy or otherwise)? GP is probably thinking of privacy risks like: "Using WiFi to see through walls" https://www.extremetech.com/extreme/133936-using-wifi-to-see-through-walls https://www.extremetech.com/extreme/133936-using-wifi-to-see... The frequencies GP is talking about are higher than current WiFi, but a bit lower than the frequencies used for the terahertz radar that can show exactly what you look like naked. So, mm wavelengths ought to be adequate to show size, position, movement, posture, gestures (probably including finger and jaw movement), sightlines, and so on, more than enough to create deepfake video reconstructions of the interior of almost any dwelling and their inhabitants, though probably not quite enough detail to be able to tell that you gained a couple of pounds this week, and definitely not enough to reconstruct facial expressions. Letting your own devices detect all that with active sensing would be bad enough, but being able to get the same info with passive sensing from outside is seriously creepy.
- Anthony-G 5y ago
  Thanks for the informative response. That sounds quite alarming and does not get much attention. I see your linked article is from 2012 – almost a decade ago. I imagine the technology must have progressed even further since then.
  - blurbleblurble 5y ago
    It's quite advanced and there are all kinds of different techniques that work, e.g. wavelet analysis, topological data analysis, deep learning, etc. Not much info on deployed applications, of course, not that I could find. Some keywords for Google Scholar: "Passive localization", "mm-wave antenna array", "device free localization", etc. I collected a few relevant articles in this comment here: https://news.ycombinator.com/item?id=22480444 https://news.ycombinator.com/item?id=22480444 But I'm afraid every time I look there are more I haven't seen before, using different variations on the lingo, such as "passive sensing" and all kinds of different stuff. Here's a video that really drives it home for me: https://www.youtube.com/watch?v=kBFMsY5ZP0o https://www.youtube.com/watch?v=kBFMsY5ZP0o

webmaven 5y ago

> Can you recommend any good summaries of developments in this area and its associated risks (privacy or otherwise)? GP is probably thinking of privacy risks like: "Using WiFi to see through walls" https://www.extremetech.com/extreme/133936-using-wifi-to-see-through-walls https://www.extremetech.com/extreme/133936-using-wifi-to-see... The frequencies GP is talking about are higher than current WiFi, but a bit lower than the frequencies used for the terahertz radar that can show exactly what you look like naked. So, mm wavelengths ought to be adequate to show size, position, movement, posture, gestures (probably including finger and jaw movement), sightlines, and so on, more than enough to create deepfake video reconstructions of the interior of almost any dwelling and their inhabitants, though probably not quite enough detail to be able to tell that you gained a couple of pounds this week, and definitely not enough to reconstruct facial expressions. Letting your own devices detect all that with active sensing would be bad enough, but being able to get the same info with passive sensing from outside is seriously creepy.

Anthony-G 5y ago
Thanks for the informative response. That sounds quite alarming and does not get much attention. I see your linked article is from 2012 – almost a decade ago. I imagine the technology must have progressed even further since then.
- blurbleblurble 5y ago
  It's quite advanced and there are all kinds of different techniques that work, e.g. wavelet analysis, topological data analysis, deep learning, etc. Not much info on deployed applications, of course, not that I could find. Some keywords for Google Scholar: "Passive localization", "mm-wave antenna array", "device free localization", etc. I collected a few relevant articles in this comment here: https://news.ycombinator.com/item?id=22480444 https://news.ycombinator.com/item?id=22480444 But I'm afraid every time I look there are more I haven't seen before, using different variations on the lingo, such as "passive sensing" and all kinds of different stuff. Here's a video that really drives it home for me: https://www.youtube.com/watch?v=kBFMsY5ZP0o https://www.youtube.com/watch?v=kBFMsY5ZP0o