The defense applications for this are tantalizing. However, given the staggering amount of room clearing that's been taking place in US military operations for the past 15 or so years, I'd be shocked if there wasn't already an existing capability to detect bad guys through walls in a CQB environment.
Through-Wall Human Pose Estimation Using Radio Signals
141–150 of 180 posts
Re: Through-Wall Human Pose Estimation Using Radio Signals
#142Earlier quoted context omitted.
How does that solve the problem of attracting talent?
It solves the problem of attracting American talent, not talent in general. Immigrants get "paid" more than citizens to do a PhD in the U.S. because there's a green card "stapled" to each degree, which is of no value to citizens but of significant value to immigrants. I called the argument "Devil's Advocate" because it is more than a little thankless to complain about someone working hard to obtain a privilege you we…
I see this sentiment quite often on hackernews. Despite having more than enough, we are just bitter than we don't have more and it's blinding us from enjoying what we have. Immigrants are just the scapegoats.
Re: Through-Wall Human Pose Estimation Using Radio Signals
#143The defense applications for this are tantalizing. However, given the staggering amount of room clearing that's been taking place in US military operations for the past 15 or so years, I'd be shocked if there wasn't already an existing capability to detect bad guys through walls in a CQB environment.
>I'd be shocked if there wasn't already an existing capability to detect bad guys through walls in a CQB environment.
Existing and exist in a state you can deploy are two totally different things that often happen many years apart. Usually something exists as an impractical wish list item for a long time before some other development pushes it into the realm of being practical to use.
Re: Through-Wall Human Pose Estimation Using Radio Signals
#144Earlier quoted context omitted.
Sometimes I wonder is this could be mitigated by literally covering your walls in aluminum foil. Maybe those "tinfoil hats" are on to something.
Just get aluminum siding, which was very popular before people switched to vinyl.
Having pulled some of it off to switch to vinyl I wish it was still readily available. It's orders of magnitude more durable than vinyl.
Re: Through-Wall Human Pose Estimation Using Radio Signals
#145Earlier quoted context omitted.
It solves the problem of attracting American talent, not talent in general. Immigrants get "paid" more than citizens to do a PhD in the U.S. because there's a green card "stapled" to each degree, which is of no value to citizens but of significant value to immigrants. I called the argument "Devil's Advocate" because it is more than a little thankless to complain about someone working hard to obtain a privilege you we…
I see this sentiment quite often on hackernews. Despite having more than enough, we are just bitter than we don't have more and it's blinding us from enjoying what we have. Immigrants are just the scapegoats.
Could you point at the part where I blamed immigrants? I knew when I posted that the HN crowd would likely hallucinate that I had done so no matter what precautions I took, but I want you to poke at that hallucination and watch your hand go through it.
I want you to understand that your mind created this mirage in order to protect you from the cognitive dissonance of telling someone to enjoy ruin at the hands of competition while simultaneously enjoying stringent protections from the very same kind of competition.
Re: Through-Wall Human Pose Estimation Using Radio Signals
#146Use ultra-wideband radio pulses, an array of a few thousand 3D printed UWB antennas and a phased-array scanning beam. You'll get a machine you could fit in the back of a truck that can scan a city block in real-time to mm precision. Sweet dreams, citizen.
Potentially not that simple, as there are fundamental limits on the information capacity of a MIMO system, based on the surface area of the volume occupied by the antenna array (in wavelengths squared). The capacity limits apply whether you use the array for communications or radar, as both are governed by Information Theory. Not to say that it can't be done, but the maths exists to definitively prove whether it can…
Yeah this is why you'd use UWB -- the capacity is insane. Also the raw information theory calculation makes sense only if you have zero prior information about the sample you're reconstructing. But 'people in buildings' is a pretty strong prior. And it's not like you have to do any extra work, just put a simulated raw signal through a neural net and regress to groundtruth data.
But let's do the math, I'm curious!
Re: Through-Wall Human Pose Estimation Using Radio Signals
#147Use ultra-wideband radio pulses, an array of a few thousand 3D printed UWB antennas and a phased-array scanning beam. You'll get a machine you could fit in the back of a truck that can scan a city block in real-time to mm precision. Sweet dreams, citizen.
So Dark Knight style imagery, all from 1 truck? What's the range?
Depends on UWB bandwidth+power, how good your processing is + how many antennas you have... You could also get way better with a fleet of trucks spaced over a large area, or a city-sized swarm of drones, or satellites...
Re: Through-Wall Human Pose Estimation Using Radio Signals
#148I've noticed, recently, that literally every major chain store I go into blocks my cell signal. I get full bars outside, perfect LTE, and about 5 ft past the glass doors, I'm suddenly cut off. Specifically, Meijer grocery stores and Home Depot are the worst offenders. Coincidentally they offer free in store WiFi to track me with, so I turn off my wifi radio on both smartphone and smartwatch before walking in the door…
You could wrap your house in chicken wire and ground it. I think that's about as cheap and easy as it can get. Might make the HOA mad, though.
Re: Through-Wall Human Pose Estimation Using Radio Signals
#149I've noticed, recently, that literally every major chain store I go into blocks my cell signal. I get full bars outside, perfect LTE, and about 5 ft past the glass doors, I'm suddenly cut off. Specifically, Meijer grocery stores and Home Depot are the worst offenders. Coincidentally they offer free in store WiFi to track me with, so I turn off my wifi radio on both smartphone and smartwatch before walking in the door…
In terms of passive signal blocking, I wonder if the chickenwire mesh that holds exterior stucco in place could serve as an effective Faraday cage? Or aluminum siding? I'm sure the metal roof and walls of a modular storage building would. Most businesses use metal studs to support interior walls, though I doubt their ~2 foot spacing would block wifi or cellular RF. In terms of active cellular jamming, that should be…
Your idea of mesh inside the stucco is way better than my idea of simply wrapping chicken wire all over the outside. Ha.
It should work, as long as it all has electrical continuity and is grounded. I think that's where a lot of normal mesh in stucco or plaster falls short; nobody is going to bother to connect it all up with copper strips or whatever if that's not their explicit goal.
Even if it's not, it should attenuate radio waves somewhat. Just not as a full-coverage Faraday cage.
Re: Through-Wall Human Pose Estimation Using Radio Signals
#150I've noticed, recently, that literally every major chain store I go into blocks my cell signal. I get full bars outside, perfect LTE, and about 5 ft past the glass doors, I'm suddenly cut off. Specifically, Meijer grocery stores and Home Depot are the worst offenders. Coincidentally they offer free in store WiFi to track me with, so I turn off my wifi radio on both smartphone and smartwatch before walking in the door…
Could it be that they had repeater antennas before, but after the LTE upgrades, they either declined to renew the repeater leases in favor of wifi+tracking or perhaps the carriers didn't want to pay for hosting repeaters?
Or a previously good cell radio nearby was moved, decommissioned, broke down, blocked by something else.