QuadRF can spot drones and see WiFi through my wall
jeffgeerling.com
jeffgeerling.com
We have a quick demo video as well: https://m.youtube.com/watch?v=QvniJk3uNyA
Along with a deeper dive video: https://m.youtube.com/watch?v=zdJ9Tbm8ALg
We didn't give Jeff great direction on camera alignment calibration or setting the radio gain but he seemed to mostly figure it out. We're improving the UI based on his suggestions (it's open source so you can customize it too)
The RF augmented reality is just one of many applications of this brand new 4x4 MIMO software-defined radio built from the ground up. The AR uses a web app to stream RF points that your phone/laptop browser then live-merges with your local camera in the browser. I've been obsessed with low latency and high frame rate to make it a truly AR experience. More technical details at https://QuadRF.com/
Do you have a demo for that 240 elements assembly?
Neat way to reduce cost and pin-count? But I think the typical FPGA clock tree has poor jitter performance. Not using the internal PLL(s) might help with spurs but the clock buffers are unavoidable.
The documentation mentions it's likely further degraded by noise from switching regulators. Oh the joys of hunting RF noise sources.
I have very little experience with MIMO / phased-arrays, this application likely doesn't need ultra high SFDR.
As I mostly deal with single channel applications, I get to use double superhet and avoid runtime calibration. Not an option here, Zero-IF has too much in the Pros column for multichannel.
I think that's why a lot of EEs and developers wind up getting an amateur radio license, or at least running a few fun RF projects.
Reading these comments first, I assumed you were using a variant of Spartan 6 LVDS TDC trick which allows up to 200 Msps rates. (https://sps.ewi.tudelft.nl/pubs/Homulle15fpga.pdf)
But this is a really interesting use case as well, and something that could be used for a 16 channel logic analyzer with analog recording support like the Saleae Logic 16 Pro, but without expensive ADC from Analog Devices.
For a deeper dive, check out any of Richard Schreier's lectures.
I'd kinda like something like this that could do 2.4GHz, 850-950MHz and even down as low as 400MHz.
Would by uneducated guess that 2.4GHz antennas would be twice the size, 900MHz about 6 times the size, and 400MHz about 10 times the size?
And cool to see you guys are from Santa Barbara. Lots of relevant talent there :)
Is a 2.4Ghz version mostly about the larger physical size? Or are there other technical limitations to overcome as well?
And cost wise - would it be 2x this version ($499) - or higher?
did I misunderstand the question?
The occupied ones, presumably. But why is Ukraine broken up? Surely, you will be dealing with a government, and they'll know what to do/ where there current borders are.
Rx/TX isolation?
Typical image rejection (dB)?
Does it support hardware level timestamping to align tx and rx samples through soapy?
[0] https://www.prnewswire.com/news-releases/the-future-takes-fl...
Future networks using millimeter-wave (mmWave) and sub-terahertz (THz) frequencies may collect or infer detailed information about people, devices, bystanders, passive objects, and environments in a sixth-generation (6G) deployment area. It may detect breathing and heart rate of biological bodies.
I'm not a conspiracy theorist but I'd say all the people working on that shit got hired.
Sorry not sorry for the run on sentence.
You only need to apologise to yourself really.
This could be both for small scale things (e.g. which part of this is squeaking?) or large scale (e.g. is that booming noise coming from the construction a few blocks away?)
https://www.fluke.com/en-us/product/industrial-imaging/fluke...
I think a few people have made homebrew versions too, like this one mentioned on HN: https://news.ycombinator.com/item?id=45137584
fluke $25k
flir $10k
td2 $1k
These are the kinds of things you look at and think - maybe I DO need night-vision, or a soldering iron with a cpu, or a thermal imager, or a steerable endoscope or now an acoustic imager....
https://x.com/ThermoInstagram/status/909356506059026432
Also for checking if microwaved food is ready.
Priceless on one occasion for finding leaks in the ceiling, which are notoriously hard to pinpoint.
oooh my. My studfinder is always a little uncertain. I would love a second opinion.
Could one of these tools help map water pipe routes and trace a leak, or are they only going to be useful for air and gas leaks?
You should definitely try a thermal camera. Any moisture will create small temperature differences which are easily picked up by a thermal camera.
A leak only turns invisible if the water has the exact same temperature as the wall and there is no meaningful evaporation happening (as that cools the affected area).
Of course don't let me stop you from actively probing your all using RF. Though also there you might have good chances with IR, since wet $stuff should behave differently than dry $stuff ;-)
There is a man call leak detective, who hunts for leaks in the UK. one tool he has is shutting off the water and filling the pipes with gas and using either sound or gas detector to pin down leaks.
A lot of the time he just listens though.
Our ears and eyes are very high bandwidth sensors.
Very cool stuff, can be used for drone detection at up to 200m. Accuracy is not super good, unless you make mic spacing a bit large.
You need really high clock rate sensing to differentiate the arrival time for sound from microphone arrays where they are all less than a nanosecond separated from each other.
Sensors around 12.5 inches apart will be a millisecond separated. The actual device was from a fuzzy recollection of a picture I saw, was probably 700 microseconds across. But it was a sphere with many sensor so adjacent sensors were less than .1 ms of separation. They would have all the time in the world to calibrate such a thing.
My guess is rather than triangulation, they probably just find the two microphones with the widest phase separarion between their signals and draw a line back between them. I don’t actually know how much 3D sonic math they’re doing.
What I do recall is that it was tech that had recently reached the Cheap Enough to Use status at the time, which is about 20 years ago now?
On balance, I would say this RF version was 200x harder.
Making the hardware is fairly achievable without having to do fancy things. but if you want >8 channels you'll need to make some custom interface hardware.
How are they planning on distributing a shared, highly precise clock for that purpose? That's already a PITA if you do QO-100 modes that need high precision, but usually there it's enough to have one good clock that you feed to the LNA... but here? Every single one of these modules needs a very precisely identical timing signal and the kind of chips you can use to multiplex a reference clock signal are pretty expensive.
I have heard claims of devices (mostly TVs) supposedly coming with secret 5G cell uplinks built in [never heard a specific model mentioned though].
If there were more variants covering more commonly-used RF bands, people could walk around and literally check for once.
(incidentally i'm sure three letter agencies have had this sort of tech in their bug-detecting toolkit for a LONG time)
Not all mobile data APNs go to the Internet. You can't resell an IP service that lands on an RFC1918 network with exactly one IP:port available; the API endpoint.
Not saying I've seen this in devices, but I have built and run mobile data networks with private APNs.
I've seen so many random industrial devices and parts come into our plant that have their own cellular it's wild.
In a television it's an added cost and it's unclear if serving ads really can offset that extra $25-100 of hardware (and included data) you ship on a $200-1000 television.
It's also unclear to me if the low data packages they come with would be enough to serve meaningful ads to begin with. Those devices usually come with a fixed plan of 100MB/month for 5yrs (or along those lines). Modern smart tv ads are very often video or at least hi res images.
Amazon seems to have done the math and found that it makes sense to give a $20 discount on a $180 device if it lets them display very unobtrusive ads on the lockscreen. So I don't think you are correct.
> extra $25-100
Your estimated costs are off by at least one order of magnitude, probably two.
Of course none of this makes much sense in a world where smart TVs have ubiquitous wifi, most consumers have one, most consumers run the stock OS, and most consumers connect it to the public internet. It would be entirely viable if not for that status quo.
Well... most TVs already have a WiFi/BT chipset for stuff like advertisements or, especially with Apple, high-bandwidth video streaming. There is already a radio module present, but (IIRC) you don't have to disclose what exactly that module is capable of.
This is occasionally mentioned on HN, but I have not yet seen a specific instance of this. Please share if you know something about secret 5G cell modems used to spy on people.
It's going to been pretty wild to see QuadRF being applied for things. I can only imagine there are weapons-technologists who will bolt this onto hunter/killer drones at some point. A lynchpin technology for the inevitable drone wars.
From documentation, QuadRF: Operating frequency range of 4.9 - 6.0 GHz (C-Band).
It would be great to have a wider range like other SDRs but of course the cost will increase exponentially.
RF drone detection has been a challenging problem for quite a while. Lots of solid state radar/RF detection products have emerged in the space, but it is not a trivial problem. And that is for drones with active RF comms, anything flying autonomously is even harder to detect at a far enough range to actually do something about.
Correct, there is no bullet proof cuas system to this date.
> anything flying autonomously is even harder to detect
Not just autonomously, because even in autonomous mode you would still need other RF like gnss, but you can fly drones without any rf signature at all and utilize a pre captured images saved on board to navigate the drone accurately using its cameras (normal or thermal). In this case, rf interference won’t work, it won’t be detected based on rf signature either, you will have to rely solely on visuals and acoustic, fly at night, and only left with acoustics.. it is a very hard task from technical standpoint.
I had a friend who'd just gotten out of EE school as a non-traditional student who was working for a company that was making radars for tracking drones maybe five years before the 2022 Russian invasion.
That was an active system, similar in concept to the radars used in air defense system just scaled down and faster acting.
The one in this article is a passive system that sees the transmitter on the drone. The comm link is the obvious weak spot on the drone as it can be detected and jammed, it is fairly inevitable that lethal attack drones that work anonymously will be widespread as a result.
Isn't most drones run by fiber optic nowadays around the front-lines though? Can't really jam those, but maybe still detect it somehow?
There are some more advanced anti-drone measures at work: Like blasting them with directed high-energy microwaves to destroy the circuits.
Both can be used for targeting.
So I’m pretty sure avoiding jamming by a military adversary is not trivial, even with frequency hopping and suchlike.
However, as pointed out elsewhere in the thread a lot of these jamming arguments are academic because drones are either tethered with a fiberoptic cable and/or navigating autonomously.
This is a bog-standard phased-array RDF calibrated for WiFi freqs; that stuff is already in every single defense show.
Also, that's why there's jamming everywhere (to blind that kind of things) and why many UAVs are now tethered to optical fibers instead of being RF-controlled.
Really depends; there you can see both Lockmart exhibiting multi-billions project, and 150m after some Serbian company selling jet engines for UAVs for a couple hundreds.
The first phased array systems date back to 1905.
We have had some time to productionize this.
Hell, the "PA" in "PATRIOT missile" stands for "Phased Array".
The new thing is that it's available for purchase for a reasonable price.
Phased arrays are nice when you want to scan a large angular surface very fast; when it comes down to optimizing RF radiation toward your ground station, a gimbal is cheaper, simpler, and works fine.
Being able to do local soft-run testing on-site to be sure that you eliminate the easy 90% of issues before you get to the lab would be a huge win.
This seems more useful for finding unknown or hidden RF sources, for instance looking thorugh an entire building to find unknown RF sources, or maybe a whole complex assembly like a car or aircraft.
Sure, maybe this isn't the device for that... but the idea that what I said was objectionable is just bizarre.
This seems more like a tool for checking across entire large assemblies like an entire building, car, aircraft, etc, for unknown sources. If you have an individual discrete device that you're already testing, just using traditional instrumentation seems reasonable, but on a large, complex assembly, I can see it being useful. Also useful for things like detecting if a particular antenna is working without actually going up there to measure near it; if you have a MIMO setup with multiple antennas, this might make it easier to check if all of them are working correctly when mounted in inconvenient areas.
[1] https://en.wikipedia.org/wiki/List_of_software-defined_radio...
They came out at $500
Being off by a bit is fine. Being off by 5x to 10x is.. Yikes.
Point still stands that they initially said it would be $50-$100. And its going for $500.
[1] https://www.reddit.com/r/homelab/comments/1uso8u1/insanity/
[0] https://www.microcenter.com/product/702590/raspberry-pi-5?rd...
See the 6-pack: https://www.crowdsupply.com/scale-rf/quadrf#products
I don't understand what this is trying to say. Everyone who has ever used wi-fi knows that it works through walls. You try to connect to a wi-fi in an apartment, and there are dozens of other networks showing up.
So this headline just seems...meaningless?
Odd, because export controls don't generally apply to published material (like open source software), but maybe they were worried that because they were also selling the hardware they could have issues due to the combo being export controlled.
Ah, found discussion of what exactly it was they pulled, it was the passive radar code: https://www.reddit.com/r/RTLSDR/comments/yu9rei/krakenrf_pul...
And indeed, they confirmed that they believe the open source software should be OK, but they had concerns because they also sell the compatible hardware: https://nitter.net/rtlsdrblog/status/1591657740229046274
Not always, but pgp wasn't exported that way until not long before there was good demand for for encryption in e-commerce anyway
> Direction finding equipment for determining bearings to specific electromagnetic sources or terrain characteristics specially designed for defense articles in paragraph (a)(1) of USML Category IV or paragraphs (a)(5), (a)(6), or (a)
ITAR part 121.
The "specifically designed for defense" probably makes this OK, but IANAL.
Title 22 Chapter I Subchapter M Part 121 - The United States Munitions List - Category XI Paragraph b
Electronic systems, equipment or software, not elsewhere enumerated in this subchapter, specially designed for intelligence purposes that collect, survey, monitor, or exploit, or analyze and produce information from, the electromagnetic spectrum (regardless of transmission medium), or for counteracting such activities.
Wouldn't that apply to every spectrum analyzer?
Since ~2022 and accelerated by the Russian aggression against Ukraine, governments are now behind both private and open source for frontier technology.
The companies that captured government contracts in the last century can’t move fast enough to bring tech into the government and national technology policy and funding is collapsing compared to the private sector
That’s new in history
Open source doesn't mean the end of competition, since we are a competitive species.
I think the future economy is going to be some sort of UBI + large open source projects
It's a really neat device, but people should realize that it has a very narrow visibility.
The lower the frequency, the bigger the antennae need to be (more or less) so a 2.4gig array would most likely be 2x the size of a 6ghz array.
Drawing a splodge in roughly the location (not sure if there's range info either? I doubt it if it's passive) overlaid on the video likely won't cut it...
One big issue with radar is that it has the same problem pilots and human observers do: it struggles to distinguish drones from anything else in the sky (birds, balloons, planes, etc.). This is an active and improving research space, but by and large with radar, when your pilots report a drone, you still don't know how to figure out if it's the typical mis-identification or something real.
And I've read about airport shutdowns in UK and US without a single arrest which is why it keeps happening
So whatever system exists, apparently not good enough
* Pilots are very concerned about life and safety and are heavily exposed to drone “incident” related anecdotes, so they err far on the side of caution with drone sightings. Which is to say a very low percentage of them are real.
* Poorly implemented cUAS systems, especially ones based on passive or active RF locating (radar) can actually make the problem worse: they hallucinate everything into drones, pilots hallucinate everything into drones, and now everything is a drone. This also happens frequently when people try to repurpose military systems (which are usually designed to operate in significantly less crowded environments and trigger at the slightest hint of an issue, due to mostly orthogonal-to-airports threat models people discuss at length on this thread like “dark drones”) into urban use.
This type of array based directionfinding system is cool and it could work as a small ingredient in a drone detection system, but it’s not anywhere near the state of the art in the space and most airports are probably already ahead of this to some extent.
It does become a bit more difficult with consumer grade off the shelf drones because it's built in. Still defeatable by the determined of course.
This gizmo is primarily interesting that it's pre-packaged at a price that hobbyists can afford.
Why so bullish on government? The department of motor vehicles is capable of being better, but they aren't.
I work primarily in sub-GHz radio. Please wake me up when they launch their LoRa version, that would be an instant purchase for me.