“Following the 12-day war with Israel in June, Iranian authorities learned that Israel could easily locate their radar systems and take them out, leaving Tehran’s forces blind to the skies above, Avivi said. Unlike the radar installations, the cameras don't transmit a signal that Israel can use to locate them, he added.”
Ukraine has a sound-based version of this, supposedly using cell phones as the primary hardware element. The idea is to scatter hundreds of sensors along the front in some depth, then use simple on-device models to classify sounds and send an alert when a sound matching a known drone signature is detected.
You can use ESP32 with GPS modules and their PPS signals. The PPS signal from the module often has has a roughly precision around 60ns against the global GPS standard.
With that signal you can PID-control an internal timer of the ESP32 - which then can be used to timestamp audio frames. Send that to a central host over Wifi and you can use your standard localization math.
The trick is to use the internal ESP32 10MHz hardware which automatically kicks timestamps into a register if a GPIO does something. Not using high-level C constructs that must eat their way through x API layers.
I've been interested in deploying something like this around my property to localize sounds that I hear just for fun.
IMO having the on-device model to pre-filter to the signals of suspected drones is potentially a good idea in a wartime environment. Not only does it conserve bandwidth (which might be a limited resource), but it also reduces airtime and thus makes the devices harder to spot.
GPS is also unreliable in Ukraine, especially near the front line.
It's unclear which approach would be better from a power budget point of view. One requires substantially more local processing power but much less radio time, while the other requires continuous radio transmission.
> GPS is also unreliable in Ukraine, especially near the front line.
There are GPS antennas that physically can block out signals that are not coming from the sky with a huge amount of decibels. Maybe Aliexpress has some of them in stock? This was heavily ITAR-ed but this ban was lifted recently.
Other option: try to sync against the DCF77 signal from Germany. Not only the beep-beep-beep time signal but also the integrated phase modulation. Jamming VLF is difficult. 77KHz is in the range of ADCs.
Then make a voter: if GPS/GLONASS/Galileo/Beidou is available prefer them, if not fall-back to DCF77. If this fails: free-running.
They claimed this bolsters defenses, but the United States and Israel have run thousands upon thousands of sorties and they’ve hit one old aircraft 30 year old aircraft?
It might, but I'm not sure how much of an issue a false positive is. It's not like Iran has an airforce and it's not like there a bunch of civilian planes flying over head.
Also, modern radar can't always tell the difference between a bird and a plane. Especially when dealing with stealth vehicles.
It's not that hard. Planes and birds act pretty differently, even when pixel sized. Doubly so when you've multiple cameras networked all over the area.
“Following the 12-day war with Israel in June, Iranian authorities learned that Israel could easily locate their radar systems and take them out, leaving Tehran’s forces blind to the skies above, Avivi said. Unlike the radar installations, the cameras don't transmit a signal that Israel can use to locate them, he added.”
Damn innovative.
It's a pretty old idea, too.
https://en.wikipedia.org/wiki/Acoustic_mirror
https://www.cnn.com/style/article/war-sound-locators-before-...
Might be good for early detection, but unfortunately doesn't provide any defense on its own.
Early detection lets you prepare the defenses.
Like getting some MANPADS teams in the route of an oncoming helicopter assault.
Huh. Reminds me of this video "tracking faint objects like stealth fighters with cheap cameras" [1] and HN post [2].
[1] https://www.youtube.com/watch?v=m-b51C82-UE
[2] https://news.ycombinator.com/item?id=43643207
Ukraine has a sound-based version of this, supposedly using cell phones as the primary hardware element. The idea is to scatter hundreds of sensors along the front in some depth, then use simple on-device models to classify sounds and send an alert when a sound matching a known drone signature is detected.
That's not even complicated.
You can use ESP32 with GPS modules and their PPS signals. The PPS signal from the module often has has a roughly precision around 60ns against the global GPS standard.
With that signal you can PID-control an internal timer of the ESP32 - which then can be used to timestamp audio frames. Send that to a central host over Wifi and you can use your standard localization math.
The trick is to use the internal ESP32 10MHz hardware which automatically kicks timestamps into a register if a GPIO does something. Not using high-level C constructs that must eat their way through x API layers.
This costs like 20€.
I've been interested in deploying something like this around my property to localize sounds that I hear just for fun.
IMO having the on-device model to pre-filter to the signals of suspected drones is potentially a good idea in a wartime environment. Not only does it conserve bandwidth (which might be a limited resource), but it also reduces airtime and thus makes the devices harder to spot.
GPS is also unreliable in Ukraine, especially near the front line.
It's unclear which approach would be better from a power budget point of view. One requires substantially more local processing power but much less radio time, while the other requires continuous radio transmission.
> GPS is also unreliable in Ukraine, especially near the front line.
There are GPS antennas that physically can block out signals that are not coming from the sky with a huge amount of decibels. Maybe Aliexpress has some of them in stock? This was heavily ITAR-ed but this ban was lifted recently.
Other option: try to sync against the DCF77 signal from Germany. Not only the beep-beep-beep time signal but also the integrated phase modulation. Jamming VLF is difficult. 77KHz is in the range of ADCs.
Then make a voter: if GPS/GLONASS/Galileo/Beidou is available prefer them, if not fall-back to DCF77. If this fails: free-running.
They claimed this bolsters defenses, but the United States and Israel have run thousands upon thousands of sorties and they’ve hit one old aircraft 30 year old aircraft?
Can they really claim this is effective?
Like Elon’s camera based self driving does it also make a lot of mistakes?
I bet modern radar can tell the difference between a bird, plane, baseball, and missile, but a camera based one is full of false positives.
It might, but I'm not sure how much of an issue a false positive is. It's not like Iran has an airforce and it's not like there a bunch of civilian planes flying over head.
Also, modern radar can't always tell the difference between a bird and a plane. Especially when dealing with stealth vehicles.
A false positive can be a problem if you're shooting missiles at things that aren't real threats, no? Those missiles cost money.
It's a problem depending on how often it happens. Letting a bomber through that takes out a military installation or desalination plant is worse.
Widely available image recognition software can tell the difference between birds, planes, baseballs and missiles already.
Depends. It would be a non-trivial problem when dealing with only 1 - a few pixels, which is likely.
It's not that hard. Planes and birds act pretty differently, even when pixel sized. Doubly so when you've multiple cameras networked all over the area.
these are infrared cameras
That's pretty cool. We need a decentralized civilian network like that to identify UFOs