So, I haven’t played with them, but even commercial, off-the-shelf DJI consumer drones have the ability to return to some location if they lose link, so they’re gonna have at least GPS in there. You can jam that, but they’ve got accelerometers, and you can’t jam that. They shouldn’t drop out of the sky even if you can manage to jam things.
It looks like DJI drones have frequency-hopping spread spectrum support, too. So you have to jam all frequencies that they’re using, since you don’t know which they’re using at any given instant. For consumer hardware, it probably doesn’t matter much – nobody is jamming you, so you sit in your little assigned piece of spectrum, have a handful of channels – but in a war, you can probably expand the frequencies you use, use a huge chunk of the spectrum, if need be.
Both Russia and Ukraine have a pretty strong interest in using electronic warfare against drones, and the fact that both are still using a lot of them seems like a pretty good argument that they can’t currently successfully stop them via electronic warfare.
And even if you can jam signal when it gets really close to the target, if you have a second drone watching – which it looks like Ukraine and Russia often are, from the videos I see, maybe to do damage assessment – you can probably stick a laser designator on those, if they haven’t already, use it to guide the weaponized drone in.
Another quick off-the-cuff improvement: the drone feeds being sent today contain a lot of unnecessary information, more than is required for a human operator to guide them in. The less information that needs to make it through, and the more you can afford to cut out and use on redundancy in transmission, the more-jam-resistant the thing is. You can fall back to a unreliable-channel mode if need be for the last bit of the approach.
Here’s a satellite source image. That’s lossily-compressed, JPEG, at 510,254 bytes. It’s pretty, but if you already know what you’re looking at and are trying to just ram it, you don’t need anything like that much information.
Here’s the same image after I’ve run a Laplace edge-detection on it, denoised it, run a threshold on it (you could probably use a simple heuristic to select the threshold, but even if not, it’d be fine for the operator to manually choose a threshold), converted it to 1-bit, and then PNG-compressed it. That resulting frame is enough to keep identifying the objects in the image, enough that if you could see that frame, an operator could hold it on-target, and it’s only 30,343 bytes, about 6% the size.
Then you can use the newly-free bandwidth to send forward error correction information – some folks here may have used it in the form of PAR2, popular in the piracy scene – so that if any N% of the data makes it through, the frame can be reassembled. Now it’s a lot harder to jam.
And that’s an off-the-cuff approach that took me about 2 minutes just using the tools that I have on my system (GIMP and PAR2) and zero time trying to improve on it. You figure that if you pay someone who actually specializes in the area to bang on this a bit, you can probably get something rather better.
Don’t take my word for it but my understanding is that your average FPV drone is much more rudimentary than a camera drone like Mavic. It’s basically just a battery, 4 motors, a camera, antenna and some flight controller chip. There’s no GPS or return to home feature as far as I know. I don’t think many of these are even able to hover on their own but require constant input from the pilot.
I don’t know if that’s true or not – at least some of them definitely do, but maybe some don’t – but those capabilities are cheap enough that they can afford to have them there if it’s what it takes to make the drone work in the presence of electronic warfare. A dumb artillery shell in the US is, from what I can dig up, about $800. The DJI drones are rather cheaper than that.
During World War II it was estimated that 45,000 rounds of small arms ammunition was fired to kill one enemy soldier. In Vietnam the American military establishment consumed an estimated 50,000 rounds of ammunition for every enemy killed.
That’s what it costs in Russia and North Korea. In the EU the costs are as I cited. And there are no production capacities at the volume required. China stopped exporting the specific type of cotton used for cordite production. Nitric acid is expensive and hard to get.
You can print billions of banknotes easily. You cant do that with millions of shells.
the difference is in different cost of workforce, different manufacturing standards, different materials, different fill, different fuze (easily 1/3 of cost),
GLSDB is cheaper than regular GMLRS rocket. ramjet 155mm is prototype. there’s another obscure 155mm ammunition called vulcano that basically packs smaller HE sabot round in 155mm, trading off payload for range, ramjet takes it even further
The accelerometers in consumer grade drones are not nearly accurate enough for inertial navigation over any significant distance. Satellite navigation is often jammed in war. The US military can degrade the accuracy of civilian GPS signals without affecting the encrypted military signals. Frequency hopping can work around some jamming, but a powerful enough jammer will overload and desensitize the receiver making it unable to hear anything.
Optical based navigation would be immune to RF jamming, but that’s not going to be found in consumer grade drones.
The accelerometers in consumer grade drones are not nearly accurate enough for inertial navigation over any significant distance.
You don’t need to fly the entire route under INS. What it will do is keep the UAV from dropping out of the sky in the presence of jamming.
Satellite navigation is often jammed in war.
To the extent of limiting reception and degrading accuracy, sure. But if all you need is the thing to have a general idea of where it is in the presence of jamming, degraded accuracy is fine.
The US military can degrade the accuracy of civilian GPS signals without affecting the encrypted military signals.
That was done via just not broadcasting some information to civilians, not jamming.
Anyone who runs a satellite positioning system can refuse to broadcast position data, but there are a bunch of global systems up there. The US has one, Russia has one, the EU has one, China has one, and other countries have regional ones. If you want to have them not broadcast data to deny someone position data, you gotta have all of the US, Russia, the EU, and China on-side. And if that’s the case, you’ve probably already won the conflict anyway.
Frequency hopping can work around some jamming, but a powerful enough jammer will overload and desensitize the receiver making it unable to hear anything.
It’s still proposing covering the radio spectrum as a whole. Traveling further along the same if you have a powerful enough transmitter that’s directional enough, you can just burn the drone’s electronics out. But nobody can actually do that.
Optical based navigation would be immune to RF jamming, but that’s not going to be found in consumer grade drones.
Yeah, and it’s going to require line of sight or a relay, like that second drone, and won’t work in all weather.
So, I haven’t played with them, but even commercial, off-the-shelf DJI consumer drones have the ability to return to some location if they lose link, so they’re gonna have at least GPS in there. You can jam that, but they’ve got accelerometers, and you can’t jam that. They shouldn’t drop out of the sky even if you can manage to jam things.
It looks like DJI drones have frequency-hopping spread spectrum support, too. So you have to jam all frequencies that they’re using, since you don’t know which they’re using at any given instant. For consumer hardware, it probably doesn’t matter much – nobody is jamming you, so you sit in your little assigned piece of spectrum, have a handful of channels – but in a war, you can probably expand the frequencies you use, use a huge chunk of the spectrum, if need be.
There are also some forms of jam resistance that AFAIK are not being exploited – beam-forming or directional antennas.
Both Russia and Ukraine have a pretty strong interest in using electronic warfare against drones, and the fact that both are still using a lot of them seems like a pretty good argument that they can’t currently successfully stop them via electronic warfare.
And even if you can jam signal when it gets really close to the target, if you have a second drone watching – which it looks like Ukraine and Russia often are, from the videos I see, maybe to do damage assessment – you can probably stick a laser designator on those, if they haven’t already, use it to guide the weaponized drone in.
Another quick off-the-cuff improvement: the drone feeds being sent today contain a lot of unnecessary information, more than is required for a human operator to guide them in. The less information that needs to make it through, and the more you can afford to cut out and use on redundancy in transmission, the more-jam-resistant the thing is. You can fall back to a unreliable-channel mode if need be for the last bit of the approach.
Here’s a satellite source image. That’s lossily-compressed, JPEG, at 510,254 bytes. It’s pretty, but if you already know what you’re looking at and are trying to just ram it, you don’t need anything like that much information.
Here’s the same image after I’ve run a Laplace edge-detection on it, denoised it, run a threshold on it (you could probably use a simple heuristic to select the threshold, but even if not, it’d be fine for the operator to manually choose a threshold), converted it to 1-bit, and then PNG-compressed it. That resulting frame is enough to keep identifying the objects in the image, enough that if you could see that frame, an operator could hold it on-target, and it’s only 30,343 bytes, about 6% the size.
Then you can use the newly-free bandwidth to send forward error correction information – some folks here may have used it in the form of PAR2, popular in the piracy scene – so that if any N% of the data makes it through, the frame can be reassembled. Now it’s a lot harder to jam.
And that’s an off-the-cuff approach that took me about 2 minutes just using the tools that I have on my system (GIMP and PAR2) and zero time trying to improve on it. You figure that if you pay someone who actually specializes in the area to bang on this a bit, you can probably get something rather better.
Sounds like a good idea. It also sounds like you know a few things about GIMP - are you subscribed to [email protected]?
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Ah, well spotted, you c*nt! Hope you have a wonderful day too!
I have nothing to add here, I just wanted to say thank you for these interesting details. An upvote didn’t feel like enough.
Thrure using analogue for the kamikazi drones no?
Don’t take my word for it but my understanding is that your average FPV drone is much more rudimentary than a camera drone like Mavic. It’s basically just a battery, 4 motors, a camera, antenna and some flight controller chip. There’s no GPS or return to home feature as far as I know. I don’t think many of these are even able to hover on their own but require constant input from the pilot.
I don’t know if that’s true or not – at least some of them definitely do, but maybe some don’t – but those capabilities are cheap enough that they can afford to have them there if it’s what it takes to make the drone work in the presence of electronic warfare. A dumb artillery shell in the US is, from what I can dig up, about $800. The DJI drones are rather cheaper than that.
To put it another way:
https://www.faac.com/blog/2018/01/28/killer-instinct-how-many-soldiers-actually-fired-their-weapons-in-past-wars-how-has-simulation-other-training-helped/
https://thegunzone.com/how-much-does-5-56-nato-ammo-cost/
By comparison, the drone is probably pretty cost-effective. If having a GPS chip is important to make it usable, cost isn’t going to be a barrier.
Dumb artillery shells are more 6000-8000 usd in the West.
googles
https://twitter.com/nicholadrummond/status/1580582881767718913?lang=en
That’s what it costs in Russia and North Korea. In the EU the costs are as I cited. And there are no production capacities at the volume required. China stopped exporting the specific type of cotton used for cordite production. Nitric acid is expensive and hard to get.
You can print billions of banknotes easily. You cant do that with millions of shells.
russia and nk uses 152mm, not 155mm
I am aware. The 3 mm calibre difference has no impact on fabrication costs.
the difference is in different cost of workforce, different manufacturing standards, different materials, different fill, different fuze (easily 1/3 of cost),
GLSDB is cheaper than regular GMLRS rocket. ramjet 155mm is prototype. there’s another obscure 155mm ammunition called vulcano that basically packs smaller HE sabot round in 155mm, trading off payload for range, ramjet takes it even further
not when there’s a shortage
GPS jamming is widespread.
The accelerometers in consumer grade drones are not nearly accurate enough for inertial navigation over any significant distance. Satellite navigation is often jammed in war. The US military can degrade the accuracy of civilian GPS signals without affecting the encrypted military signals. Frequency hopping can work around some jamming, but a powerful enough jammer will overload and desensitize the receiver making it unable to hear anything.
Optical based navigation would be immune to RF jamming, but that’s not going to be found in consumer grade drones.
AI visual navigation has already been deployed in russian drones. Not yet in low-end ones.
You don’t need to fly the entire route under INS. What it will do is keep the UAV from dropping out of the sky in the presence of jamming.
To the extent of limiting reception and degrading accuracy, sure. But if all you need is the thing to have a general idea of where it is in the presence of jamming, degraded accuracy is fine.
That was done via just not broadcasting some information to civilians, not jamming.
Anyone who runs a satellite positioning system can refuse to broadcast position data, but there are a bunch of global systems up there. The US has one, Russia has one, the EU has one, China has one, and other countries have regional ones. If you want to have them not broadcast data to deny someone position data, you gotta have all of the US, Russia, the EU, and China on-side. And if that’s the case, you’ve probably already won the conflict anyway.
It’s still proposing covering the radio spectrum as a whole. Traveling further along the same if you have a powerful enough transmitter that’s directional enough, you can just burn the drone’s electronics out. But nobody can actually do that.
Yeah, and it’s going to require line of sight or a relay, like that second drone, and won’t work in all weather.