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Tracing a powerful GNSS interference source over Europe

arxiv.org

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Re: Tracing a powerful GNSS interference source over Europe

#221

Post by pelorat »

colechristensen wrote: post #10
uijl wrote: post #6

Interesting to see that they are able to identify the specific satellite. I wonder if we can do something now that we know the source. Working on construction projects on the Romanian coastline (just South of Ukraine) and on the Polish continental waters (just West of Kaliningrad) we experienced jamming on a daily basis.

>I wonder if we can do something now that we know the source. Russia signed the 1967 Outer Space Treaty (OST) in 1967, this may be a treaty violation of this or other treaties, something like that or retaliation regarding it may be possible. You can hack the satellite, or use other electronic warfare options to jam or interfere with it's operations. You can shoot it down with a missile. The X-37B is in space right no…

Like the USA, I don't think Russia codifies treaties into law. Like in the USA, treaties for Russia are mere suggestions used as a geopolitical tool until inconvenient.

Re: Tracing a powerful GNSS interference source over Europe

#222

Post by drysine »

Havoc wrote: post #34
Schlagbohrer wrote: post #20

Earlier quoted context omitted.

That jamming near Kaliningrad must surely be impacting the Russian residents as well, right? Unless it is very carefully aimed which seems unlikely since it is also trying to cover a very large volume.

>must surely be impacting the Russian residents as well, right? They don't give a fuck. Was watching a youtube video by a russian the other day talking about war & sanction impact and things like ride sharing apps literally say on screen the location is going to be wrong and to select pickup spot manually. It's just assumed to be fucked as a given even at an app development level

>and to select pickup spot manually. It's just assumed to be fucked as a given even at an app development level

No, it's a feature that was there from the beginning - you don't always choose the location you are currently at.

>They don't give a fuck.

But yes, we don't give a fuck

Re: Tracing a powerful GNSS interference source over Europe

#223

Post by Aerroon »

colechristensen wrote: post #189
Aerroon wrote: post #14

Earlier quoted context omitted.

I've thought about this before - do you actually need to "shoot it down" (make it explode)? What if you just nudge it a little and either make it spin or change its orbit? If your missile can reach the satellite then these seem like things that should be possible, no?

A missile intercept for explosions or a kinetic destruction the relative velocity will be measured in kilometers per second. A little nudge doesn't do much, it's still a satellite in a substantially similar orbit. Any sort of nudge requires intercept, go up there and match its velocity so you can grab it and push. And still you have to push on it a whole lot to make a meaningful difference. Spin it up? You'd have to…

An apple at highway speeds can break the windshield and make the car undriveable. People throwing things from highway overpasses is a serious (and deadly) problem.

>A missile intercept for explosions or a kinetic destruction the relative velocity will be measured in kilometers per second.

The satellite will also be going kilometers per second. You have to almost match the orbital velocity to have a chance of hitting it anyway.

Re: Tracing a powerful GNSS interference source over Europe

#224

Post by mkj »

picofarad wrote: post #79
stef25 wrote: post #77

Earlier quoted context omitted.

> frying it with some sort of high powered electromagnetic pulse would seem the smartest option with plausible deniability Realistically, how many people could do this ?

If you gave me a million dollars, I could do it. Someone else would have to aim it, but it shouldn't be that hard to do.

From what distance? I would have thought $1M wouldn't go far

Re: Tracing a powerful GNSS interference source over Europe

#225

Post by AlecSchueler »

lenerdenator wrote: post #88
stef25 wrote: post #75

Earlier quoted context omitted.

That covers most of Poland, wtf

Why wouldn't it? The behavior will continue until a consequence is imposed. Not on regular Russians, mind. Their ruling class. They're still free to move about the continent, make investments, do whatever. Currently Europe seems to be more interested in breaking away from the US than dealing with the power that has killed hundreds of thousands on their own continent.

> Currently Europe seems to be more interested in breaking away from the US

The efforts taken to move away from Russia in the past 5 years clearly dwarf any de-Americanisation efforts to the point that it's difficult to take your comment seriously after this sentence.

Re: Tracing a powerful GNSS interference source over Europe

#226

Post by ralferoo »

rcxdude wrote: post #195
mrguyorama wrote: post #165

Earlier quoted context omitted.

No? Old AM radio required only rectification. You can receive it with accidental diodes.

You do generally need a tuned filter before the rectification, unless you have an extremely large signal dominating the local airwaves. Which is precisely the parent poster's point: with RF you are almost always doing something to demodulate the signal. Whether you are doing it with a sine wave or something more complicated is not that fundamentally different. (and if you're looking at a spectrum analysis, that is lo…

I'd argue that "correlation" is an accurate description of what you're doing with Gold codes - you're testing the known sequence of the output of a PRNG against the received signal, and only accepting it when the data correlates, otherwise you're adjusting the offset and trying again until you find a high correlation (strong +ve and -ve spikes) or you give up and assume there's no transmission. There's nothing in the received signal that tells you there is a real signal there at all, without correlating against every possible offset.

If you compare that to the majority of radio transmissions modulated on a sine wave carrier, there is a clear signal there and you don't need to correlate anything to tell you that, and you don't need to keep trying different offsets - you can just demodulate using a carrier of the correct frequency and the result is correct, just with a slight phase shift relative to the local carrier and which probably isn't even relevant in the frequency domain of the signal.

The key point to me is the trying repeated offsets to try to pick out a signal well below the noise floor, and choosing the offset that provides the best correlation, compared to demodulating a very strong signal that's obviously there by just adding a carrier. The latter could be done using "correlation" if you're implementing an SDR, but it doesn't have to be, and most radio hams would prefer to think of it as a simple analogue operation instead.

Re: Tracing a powerful GNSS interference source over Europe

#227

Post by CrzyLngPwd »

Geof25 wrote: post #204
CrzyLngPwd wrote: post #190

Earlier quoted context omitted.

Everything> Are you sure? They have a large nuclear arsenal; I'm sure the news would have covered it being used. What news do you follow that shows Ukraine as a hot nuclear desert?

China and India signalled to Russia that nukes are big no-no. Reason is simple - using nukes when you can't win a conventional war will degrade them from strategic asset into tactical one and whole nuclear proliferation flies out of the window and everyone will have nukes.

So, not everything, then.

Re: Tracing a powerful GNSS interference source over Europe

#228

Post by sidewndr46 »

fsmv wrote: post #207
ordu wrote: post #43

Earlier quoted context omitted.

> The theory that they broadcast communication on a band near GPS in order to discourage jamming of their early warning system sounds likely. Is it? If it is an early warning system, could it be jammed briefly so it would fail to warn, couldn't it? It will be a global disruption of GPS, but a brief one and I'm sure people wouldn't be concerned of it due to other news. > Flexing the ability to jam GPS is pointless Do…

Presumably the missile needs GPS to hit the target so if you jam right when the missile is coming in the missile will miss so you can't really jam the warning Also if you broadcast noise when your missile is about to hit then your own jamming signal acts as an early warning as well, although I guess it wouldn't provide location.

This isn't true for US made weapons. They explicitly do not use GPS because it is the first thing to go in a war

Re: Tracing a powerful GNSS interference source over Europe

#229

Post by karp773 »

jandrewrogers wrote: post #210
fsmv wrote: post #207

Earlier quoted context omitted.

Presumably the missile needs GPS to hit the target so if you jam right when the missile is coming in the missile will miss so you can't really jam the warning Also if you broadcast noise when your missile is about to hit then your own jamming signal acts as an early warning as well, although I guess it wouldn't provide location.

US weapon systems have never relied on GPS for guidance. Some will accept GPS corrections to the primary inertial guidance system but those corrections will be rejected if they deviate more than a few meters from the inertial guidance. US missiles in particular use precision terminal guidance which doesn't involve GPS at all; in these systems GPS would only be used to correct mid-course guidance. There has been anecd…

I do not think that is correct. For example, Excalibur [1] relies on GPS and proved to be quite inefficient in Ukraine. Russia figured out how to jam them in a few months.

[1] https://en.wikipedia.org/wiki/M982_Excalibur

Re: Tracing a powerful GNSS interference source over Europe

#230

Post by dyauspitr »

Schlagbohrer wrote: post #20
uijl wrote: post #6

Interesting to see that they are able to identify the specific satellite. I wonder if we can do something now that we know the source. Working on construction projects on the Romanian coastline (just South of Ukraine) and on the Polish continental waters (just West of Kaliningrad) we experienced jamming on a daily basis.

That jamming near Kaliningrad must surely be impacting the Russian residents as well, right? Unless it is very carefully aimed which seems unlikely since it is also trying to cover a very large volume.

One of Russia’s superpowers is that they don’t give a damn about collateral damage on their own people. This isn’t just a throwaway comment I’m making this actually bears out over several decades.
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