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https://www.flightradar24.com/data/gps-jamming

Also: https://gpsjam.org/ | https://hn.algolia.com/?q=gpsjam

(am I missing any other GPS jamming mapping or data collection projects?)

Worth adding that gpsjam does the exact same thing with ADS-B data.
This map is basically copied from GPSJAM.org, which started a while back.
Thanks for linking gpsjam -- flightradar24's map is total trash by comparison (colours, lack of borders).

Does anyone know if a similar service covers things like GLONASS, Galileo or BeiDou?

EDIT: nevermind, these services can't distinguish. From the FAQ:

> The ADS-B data used by this map includes information on the accuracy of the navigation system used by each aircraft, but doesn't specify the type of navigation system. It could be GPS, another global navigation satellite system (GNSS) like GLONASS, or it could be an inertial navigation system (INS). My understanding is that most aircraft are using GPS, so that's probably mostly what the map shows.

Flightradar24's visual representation definitely sucks, but comparing the two, gpsjam has a lot of unexpected missing areas across Africa, South America, and SE Asia that at least have some data on FR24.

I'm not sure if that means FR24 has a better dataset, or they're processing it differently or if they're just extrapolating from few data points when they maybe shouldn't be.

It would be awesome if they published this data more openly for academic use!

Edit: Looks like they might source their data from commercial ADSB providers. Bummer

They are the commercial ADSB provider
Hey, I'm living in one of these cells in Germany. Hmm.
They are fairly large cells. I assume the “bad” cells are displaying some maxima-based aggregate rather than implying the whole area (or a large part of it) in them is noticeably jammed.
Also, the reports are coming from aircraft which have a much larger horizon at altitude. The jamming from Kaliningrad probably doesn't have any effect on the ground at long distances.
Turn off WiFi location in your phone and see how long it takes for it to get a GPS fix, or if it never gets one.
Many of the patches are not surprising, but why is a small area between Germany and Sweden jammed?
A small area between Estonia and Finland likewise.
Any chance the area being referenced in relation to Germany is near the headquarters of a company named aaronia? They manufacture, high-end spectrum rf analyzers, and high-end drone tracking and jamming/drone disabling equipment. (As a result, I would expect them to be testing, and or demonstrating their equipment near their headquarters.)

Just a guess/speculation as I’m familiar with aaronia’s products and services (indirectly)

If any civilian company jammed GPS enough to affect commercial aviation that would be a huge no-no - RF emissions in places like Germany are strictly controlled, even if you're just 'testing'
If you click through some different days, it looks like that is just a patch of the larger overall jamming zone around Kaliningrad.
(comment deleted)
I wonder why there's some jamming near a small section of the Texas/Mexico border?
Drug Cartels most likely. That area is frequently jammed.
That is Eagle Pass, TX. The infamous, massive border crossing area where suspected criminal border crossers are corraled under the bridge, where Elon visited, etc.

The jamming is done to make crossing the border without going through the checkpoint more difficult

Is there some official source for that? If so, is it just GPS or do other GNSS constellations get jammed too?
Since even phones can receive and understand the other systems' signals, if one wants to jam, one would probably jam them all...
Do these cartels only operate during normal US workday hours and observe US federal holidays?
That's north of Eagle Pass. Laughlin AFB is on the southwestern edge of those two red cells. Eagle Pass is like 50-60 miles south.
I'm curious as well. My first thought was cartels, but it's also right over Laughlin AFB.
You're not the only person: https://web.stanford.edu/group/scpnt/gpslab/pubs/papers/Liu_...

TL;DR: It's weak signal, not jamming. The weak signal reports come from military training aircraft carrying out maneuvers that cause temporary signal loss.

really? unless they're jamming it, how would that happen?
(comment deleted)
Rapidly execute a series of maneuvers (flips, rolls) that cause the radios to lose signal.
So I'm a little skeptical on that front because military aircraft are still not that often broadcasting ADSB even during routine flights, at least in my (also close to the border) region. In theory the Air Force was supposed to have completed ADSB installation on their fleet last year but they blew the deadline pretty bad on even installing transponders, and of course they still reserve the right to disable them during military operations.

Maybe with the data we can figure out what portion of military flights are included?

For the helicopter training flights that I notice most often, it's still rare to see one that broadcasts ADSB, probably <10%. C-130s usually don't either here but it's more often, maybe more like 25%. Perhaps for other categories of aircraft they've installed more transponders. But in the city where I live, even passive mode-C MLAT is probably around 50% success on tracking military flights for ADSB Exchange. FlightAware might have better coverage for mode-C. mode-C can't contribute to this GPS reliability data anyway but it illustrates that even C-130 pattern practice is sometimes "stealth" from a radio perspective due to the low installation rates for ADSB and difficulty of good mode-C coverage.

The paper linked elsewhere (https://web.stanford.edu/group/scpnt/gpslab/pubs/papers/Liu_...) mentioned issues with military training flights resulting in spurious low-NIC cases but unfortunately doesn't quantify it. With the way the AF rollout has gone it probably depends on the specific installation, command, and aircraft type.

In the border region specifically we would tend to expect the majority of non-military flights to be civilian CBP aircraft that aren't performing unusual maneuvers. CBP has a somewhat complicated and limited authority to disable ADS-B that I don't know the contours of, I'm not sure how often they do so on their larger (non-sUAS) aircraft. Involvement of the Air National Guard in the Texas area might complicate the analysis though.

How does not having ADSB impact air control?
ATC is used to working with military aircraft without ADSB since it's been the status quo (and keep in mind that ADSB is not required on aircraft in general, although the set of airspace situations in which it's required has been expanded over the years to become a de facto near universal mandate). But the FAA doesn't like it, which is why they set the deadline for the Air Force to install ADSB, which the Air Force missed.

Military aircraft on military maneuvers don't deal with FAA ATC, the military has its own controllers. It's mostly an issue when they're operating near civilian airports (or the many, many military facilities that share an airfield with an airport). There are still adverse safety impacts to the lack of ADSB on many military aircraft, in that it defeats things like TCAS.

Actually this topic is slightly complex and I think a lot of people have misconceptions, so let's lay it out. These rules have gotten stricter and stricter in recent years.

1. ADSB is not required. Meaning, there is no universal requirement that aircraft be equipped with ADSB, and plenty of aircraft still legally operate without.

2. ADSB is required in class A, B, C, in many cases in class E, and within the "Mode-C veil" surrounding major airports.

3. ADSB is required in any case where a transponder is required, for those edge cases that are not included in the above.

4. The result is that the areas in which you can legally operate without ADS-B are mostly limited to low altitudes in rural areas. Of course, this encompasses a large portion of hobby aviation especially, but not very much commercial flight.

I can say that in San Antonio where I live and also operate a ADSB receiver the dedicated air force flight trainers (T38 Talons and T6 Texans) routinely fly with ADSB on. The C5 cargo plans also fly with ADSB on when doing training but I've seen non-training flights fly overhead with ADSB off.

I can actually receive high flighting planes over Del Rio so it would be interesting to see if they are reporting bad NIC values.

I thought Mode C was just barometric pressure data measured by the aircraft. It's related to altitude, not position, so there's no such thing as Mode C "coverage".

e; oh wait you said passive MLAT off Mode C, that makes more sense then

Yep, this map doesn't show jamming. It shows weak signals, of which jamming is one potential cause. An airplane pointing their GPS receiver at the ground will also cause a weak signal.
How does an airplane "point their GPS receiver at the ground" (for an extended period of time since a combined GNSS/INS positioning solution, which is what all airliners use at this point as far as I know, will need an extended signal loss to report decreased accuracy)?
Probably something like this

https://youtu.be/Ynvoriv09Ks?t=105

Ah, is this Ryanair's plan to divest from their all-Boeing fleet? :)

It should be pretty simple for Flightradar24 to exclude non-commercial aircraft from the data through, which would solve that problem.

There's also tons of data available in the ADS-B signal that should help distinguish between aircraft-motion-induced outages and actual jamming: https://mode-s.org/decode/content/ads-b/7-uncertainty.html

From the FAQ, it sounds like they simply presume that anywhere with multiple low NIC values is indicative of interference.

> The GPS interference data is derived from NIC (navigation integrity category) values that we receive as part of the ADS-B protocol. We mark regions as affected if a significant number of flights in that area report lowered NIC values.

Unfortunately some of the data that's most directly applicable to determining aircraft attitude, like roll, is optional and rarely sent by aircraft, but yes I'm sure you could do a decent job of inferring maneuvering from change in heading and vertical rate (especially if you're looking at ADS-B data with high temporal resolution vs., say, every 10-60 seconds.)
on a pure radar scan, what would return of formation flying like this look like to a radar operator? is it just one large dot, or can they distinguish the number of planes in the formation?
It happens when you are giving the bird.
That's a good link (that I should have posted). I suspect that some of the yellow (maybe even red) hexes in the U.S., and maybe some in Europe too, are due to that effect.

For people doubting that aircraft maneuvering can affect navigation accuracy as reported by ADS-B, I found a fun example. Around 1300 UTC today (0800 Texas time), 4 T-38s took off from Laughlin AFB for what looks like training, with lots of maneuvering. This link shows what it looks like when mapped in 2D: https://globe.adsbexchange.com/?icao=adffc3,adfff9,adffd2,ae...

Here's a 60 second segment of the track of one of those jets, STEER21, that captures a steep turn and dive: https://globe.adsbexchange.com/?icao=adfff9&lat=30.067&lon=-...

If you click on the track, you can inspect the ADS-B data at that point in time in the sidebar on the left. If you scroll to the bottom of that sidebar, there's an "ACCURACY" section, that shows the Estimated Position Uncertainty (EPU). You can see it change from better than < 30 meter uncertainty to > 18.5 km(!) uncertainty as it performs the maneuver.

I made a video that shows how to see those values, and also shows the maneuver in a 3D viewer so you can see how steep the dive is (it's steep!): https://www.youtube.com/watch?v=jfHlpnEdHxw

(The viewer uses a generic aircraft model, FYI, don't be distracted by that.)

(comment deleted)
Can't the US military turn it off in some areas. Law enforcement wouldn't have to jam.
Is the data actually interesting? I feel like any place that would have widespread jamming would also see routing away of non-military aircraft meaning you'd never see the jamming taking place except if you happen to get lucky and the jamming zone is larger than the "stay out" zone. This makes sense then why the map is entirely green with some red just at the periphery of Ukraine with the majority of Ukraine having no data since it's a no-fly zone for civilian traffic.
The jamming over Kaliningrad affecting civil aviation has made the news recently, and the map does provide some interesting insights both how far the effect reaches into Poland and Sweden, and how often it is turned on and off.
If you read the article, jamming is based on uncertainty of the aircraft, just because it's uncertain, doesn't mean that it's dangerous level of uncertainty
This is a case where nominally, with a solid understanding of geopolitical events, maybe it's not interesting on average. BUT, all of a sudden something might pop up one day. The accessible, "crowdsourced" data is helpful to have in those cases.
Why in the world is there so much jamming in Turkey? What's going on?
Iran maybe?
Red dots are in the north of Turkey. I don't think that Iran reaches there.
Turkey has been jamming GPS for years. I can't find a good explanation.
(comment deleted)
To the north is the Black Sea, and the Russia-Ukraine war. To the east is Armenia and Azerbaijan (as well as Iran). To the south is the middle east. Also Cyprus with the frozen conflict, there.
In addition to Armenia/Azerbaijan, Turkey has had a significant internal conflict with the PKK (Kurds) in the East/South East for... a very long time.

Also that whole region is just patchy with flight data - it makes it difficult to really see the true shape of jamming.

> Turkey has had a significant internal conflict with the PKK (Kurds)

PKK the terrorist organization, yes. Kurds the ethnic group, no.

> > Turkey has had a significant internal conflict with the PKK (Kurds)

> PKK the terrorist organization, yes. Kurds the ethnic group, no.

The Turkish government has a decades long history of discrimination against Kurds, including banning their language, even denying their existence as a people. If Turkey had treated Kurds better, PKK may well have never existed, and almost certainly would not have had as many Kurds supporting it even if it still had.

https://en.wikipedia.org/wiki/Human_rights_of_Kurdish_people...

https://en.wikipedia.org/wiki/Denial_of_Kurds_by_Turkey

https://en.wikipedia.org/wiki/Xenophobia_and_discrimination_...

Turkish Government has had many high-ranking Kurdish officials, including multiple presidents and prime ministers.

There have been more Kurds served in the Turkish Army than all the other armed organizations combined.

Majority of Kurds in Turkey openly support the Turkish Government, especially against the PKK terror.

Several Kurdish organizations in Iraq, Syria, and Iran support the Turkish Government, especially against the PKK terror.

PKK kills Kurds. PKK kills Turks. PKK will happily kill you if doing so benefits the crime and propaganda business they have been profiting for decades.

Let's not parrot some politically charged material as facts without having any actual understanding about such sensitive matter.

According to Wikipedia [0]:

> The Kurdish language was banned in a large portion of Kurdistan for some time. After the 1980 Turkish coup d'état until 1991 the use of the Kurdish language was illegal in Turkey.[52]

> Before August 2002, the Turkish government placed severe restrictions on the use of Kurdish, prohibiting the language in education and broadcast media.[55][56] In March 2006, Turkey allowed private television channels to begin airing programming in Kurdish. However, the Turkish government said that they must avoid showing children's cartoons, or educational programs that teach Kurdish, and could broadcast only for 45 minutes a day or four hours a week

It is true that over the last 20 years or so, the Turkish government has relaxed many (but not all) of its anti-Kurdish laws and policies. But that doesn't erase the reality of the decades of oppression which proceeded it.

[0] https://en.wikipedia.org/wiki/Kurdish_language

In the 1980s, Iraqi Kurds were fleeing to Turkey for freedom and safety. The Prime Minister was of Kurdish origin. You could hear people speak Kurdish freely anywhere between the west and east end of the country.

There were no "anti-Kurdish" laws and policies. The pro-American coup d'état in 1980 came with a law to control non-Turkish publications, but it was never put into action.

> There were no "anti-Kurdish" laws and policies.

Here's a 1999 Human Rights Watch report – "RESTRICTIONS ON THE USE OF THE KURDISH LANGUAGE" – https://www.hrw.org/reports/1999/turkey/turkey993-08.htm

You can't just dump links to 10,000-word political essays, and expect them to support your original premise that the PKK terrorism is justified.

You must have a knowledge about the history and currency of the topic to hold such strong opinions. You should also use your own words to articulate your arguments, so I can keep myself engaged in this conversation.

Nevertheless, I've read the report. It misinterprets the government's certain actions to protect the public against several jihadist, separatist, and other destructive movements, which are not exclusive to a specific ethnic group.

It also fails to recognize the newly founded republic's goal to build an inclusive Turkish citizenship identity, and to provide a progressive and secular education program to everyone regardless of their race, religion, and gender while preserving the cultural value of each.

"Kurdish" isn't a single language anyway. There is a reason Kurds use French in France, English in USA/UK/Canada, and Turkish in every part of Turkey to communicate with each other, unless they're from the same tribe. It's not realistically possible to institute a system to provide public service to every individual without establishing a common ground.

> You can't just dump links to 10,000-word political essays,

I'm citing reputable sources, your reply is just your own say-so.

If you don't like Human Rights Watch, how about the European Commission?

https://projects.research-and-innovation.ec.europa.eu/en/pro...

> and expect them to support your original premise that the PKK terrorism is justified.

I'm not defending attacks on innocent civilians. Consider Northern Ireland: the IRA's attacks on civilians were shameful and wrong. But, if it were not for the oppression of Catholics by the Stormont government, and the failure of the UK government to stop it, those attacks may well have never started.

You're trying to connect the dots between two separate phenomenons. This oversimplification will only mislead you.

You'd think that your left-wing instincts will guide you through this, but you will accidentally end up taking ugly sides in proxy wars in this part of the world.

PKK started out according to CIA's Operation Gladio to justify the 1980 coup, and continued operating in line with the Carter Doctrine. Its first actions were assassinating Kurdish and Turkish left-wing leaders (Zeki Ön, Mehmet Ongan, Adil Turan, Hasan Erkılıç to name a few).

Today, PKK follows the radical Islamist narratives (Şeyh Said, Seyit Rıza, etc. are often celebrated by them). PKK is in agreement with an Islamist terrorist organization (FETÖ) behind the 2016 coup attempt, whose leader (Fethullah Gülen) resides in the US. PKK conducts international drug trafficking at "cartel" scale (between Asia and Europe; ask your neighborhood drug dealer about it). PKK is backed by several crime syndicates and tribes who are responsible for countless human rights violations from systematic child/woman abuse to forced labour and human trafficking. PKK is currently taking part in the ethnic cleansing of Arabic, Turkish, Assyrian population in Syria and Iraq to make a space for an American-backed puppet state under "YPG" alias.

How is your IRA-PKK correlation shaping up now?

Your "reputable sources" are compilations of quotes by "usual suspects" anyway. Western organizations are not known for being the gold standard of social justice advocacy here, as they have a history of endorsing any "project" that fits their financial and political agenda; from cyanide process in gold mining, to civil warfare for carving up sovereign states.

So how should I interpret this? The map lacks geopolitical boundaries, so it's hard to interpret.

There looks like a big hole of no data over Ukraine, where I'd most expect GPS jamming, but I suppose there are no civilian flights either. Maybe they could setup an GPS observation station on the ground at a surveyed point to get data there.

There's a big red blob over Turkey, is that maybe the southern edge of the reach of Russian jammers in the Black sea?

There's also a big red blob over the eastern Mediterranean. Is that Israel? I'm not so sure though, because it's not centered on Israel and parts of Israel proper are green on the map. I also assume they're heavy users of GPS, so wouldn't want to jam it.

There's a red blob in Southeast Asia, and that looks like Myanmar, where there's a civil war right now.

There's a little red blob over what looks like Kashmir.

I was curious too. Did some sleuthing, it looks more like Punjab. I think that’s to block drone infiltration from Pakistan [1]. It does change going back to 14th March there is no jamming in the region, US and Europe blobs also reduced, so I think this stuff is event driven, wonder what goes on, fascinating stuff.

[1]https://www.thehindu.com/news/national/other-states/over-100...

Or could it be related to the farmer protests?
Their data comes from commercial flights. If there are no flights, there's no data. There aren't many commercial flights over Ukraine or Belarus right now, so that whole area's empty.
ADS-B is only commercial flights? I thought many kinds of flights are broadcasting. Does Flightradar24 only track commercial flights?
I doubt there’s any private flights over Ukraine too. Military planes generally don’t advertise their location in combat zones
> Military planes generally don’t advertise their location in combat zones

They might if they are from countries neutral to that conflict, like NATO flights over the Black Sea.

No flights at all.

About three or four civilian aircrafts were able to leave Ukraine during the war and every departure was a major military operation to undertake.

It tracks private flights too. I'm only tangentially familiar (though I have an ADS-B receiver reporting to FR24), but my understanding is that it's not required for private flight now, but more and more aircraft are being retrofitted.

Actually, it's more about airspace:

https://www.aopa.org/go-fly/aircraft-and-ownership/ads-b/whe...

"The FAA requires ADS-B Out capability in the continental United States, in the ADS-B rule airspace designated by FAR 91.225:

Class A, B, and C airspace;

Class E airspace at or above 10,000 feet msl, excluding airspace at and below 2,500 feet agl;

Within 30 nautical miles of a Class B primary airport (the Mode C veil);

Above the ceiling and within the lateral boundaries of Class B or Class C airspace up to 10,000 feet;

Class E airspace over the Gulf of Mexico, at and above 3,000 feet msl, within 12 nm of the U.S. coast."

The hole over Ukraine is definitely the lack of civilian flights.

Another notable spot is Kaliningrad, the Russian exclave. It looks relatively normal on some days, like today, but on others like yesterday it's covered by solid red stretching far into Poland, Sweden and even Germany.

> Another notable spot is Kaliningrad, the Russian exclave. It looks relatively normal on some days, like today, but on others like yesterday it's solid red.

Oh yeah, I totally forgot that was a thing, and that explains that spur of red in the Baltic. I'd (probably incorrectly) assumed it was some kind of spillover from jamming in Ukraine.

I didn't realize you could look at it over multiple days. One interesting thing about that blob is the outline of red seems to always be there, in the same shape, but the middle is often green. Maybe that's some artifact of their agreement algorithm? More overflights around the edges than through?

It also looks like there's some jamming in Estonia? Or maybe that's just the edge of jamming around St Petersburg?

Russians do plenty of jamming that expands beyond their borders in the Baltic, either on purpose or just as a spillover as they don't care. Before Finland joined NATO they used to also violate our airspace on frequent basis, but since then that has stopped.

https://yle.fi/a/74-20079715

They violated NATO airspace a lot with their "Bear" nuclear-capable bombers until very recently. Not sure if it's still happening. It was so frequent that it didn't make the news every time.
The idea that russians are doing these things 'by accident' ain't even funny, just dangerously naive and nobody from intelligence community thinks so. They know damn well what they do and its well planned and even heroic in some childish fashion in their f*cked up mindset.

They are at war with west (more Europe than US though) for solid 2 decades straight, just that they started to use military only in last decade, but were subverting public opinions in usual command & conquer strategy for much longer (riling western and former soviet populations against EU and Nato, supporting ultra-right groups, spreading false rumors ie on covid in us vs them psi-ops).

Whatever politicians on their side say is meaningless or diversion and definitely just wasted time, just look at actions alone.

I never said it was by accident. It surely isn't.
> Before Finland joined NATO they used to also violate our airspace on frequent basis, but since then that has stopped.

Probably temporarily. They violate the Estonian airspace on a regular basis with military planes, with their responders turned off. The NATO planes stationed in Estonia then take off and go see them off.

[flagged]
Earth is temporarily occupied by humans, too.
The universe is temporarily occupied by stars.
Correct me if I'm wrong, but AFAIK Germany is the one country where even far right parties don't want to touch the topic of old territorial claims.
[flagged]
Please do not react on a trolling statement by a reverse trolling statement. It kills discussion and makes people more dumb.
Yea, oddly, if you go back to like august, there's still a bunch of red over the Mediterranean, parts of Israel, Jordan, Lebanon, etc. so it's not totally clear what that is. I've heard anecdotally that gps has gotten unusable in Israel in recent weeks but it's not clear why that's changed based on the mapping information we're seeing here.
Northern Israel is completely jammed. There's talk of Israelis getting matched on Tinder with women from Beirut.
That’s because Beirut is 60 miles from northern Israel and Tinder’s max is 100 miles IIRC. These are small countries we’re talking about here.

Phones don’t use GPS these days if they can help it - WiFi triangulation is significantly faster and uses much less battery - so GPS jamming wouldn’t have anything to do with Tinder matches.

This didn't happen before the war started.
Probably some new-age hippies at Tinder taking the 'make love, not war' manta to heart. /s
I see 2 red cells on the US/Mexico border right about Texas/Coahuila region. Navigating that dessert region without GPS or with GPS for that matter can be deadly.
That's the most curious jamming I see on the map—anybody know why jamming is present there? Is there a military base in that region?
U.S. military has some Very Secret Stuff happening in certain desert areas.
Laughlin air force base is there.
Organized crime in Mexico would probably do it to prevent other people from using migration routes they control and reduce police efficacy. Of course, slightly rogue Mexican police or even US vigilantes also have an incentive.
The Eastern Mediterranean might be the (significant, underreported, under-remembered) Russian military presence in Syria. They have airbases, a naval base, they rotate and train their officers there, they constantly ship military equipment back and forth from the Black Sea ports via the Bosphorus to Syria, they train the Syrian army, they build human shield observation posts overlooking Israel.

What's unfathomable to me is how Israel (or Netanyahu?) keeps treating them as a frenemy.

It's kind of neat how this works:

> As part of the ADS-B messages we receive from each aircraft, the Navigation integrity category (NIC) encodes the quality and consistency of navigational data received by the aircraft. The NIC value informs how certain the aircraft is of its position by providing a radius of uncertainty.

> Poor NIC values alone might indicate a problem with an aircraft’s equipment or unfavorable positioning. However, when observed in multiple aircraft in close proximity during the same time frame, it suggests the presence of a radio signal interfering with normal GNSS operation.

A single observer can't really say for certain that jamming is happening; you need a distributed sample from multiple different sensors over a period of time to have reasonably high confidence.

> A single observer can't really say for certain that jamming is happening; you need a distributed sample from multiple different sensors over a period of time to have reasonably high confidence.

Could you use RTLSDR triangulation to hone in on granular lat long of jamming sources?

https://www.rtl-sdr.com/detecting-gps-jammers-in-augmented-r...

https://www.rtl-sdr.com/kiwisdr-tdoa-direction-finding-now-f...

You can get rough areas with a GPS and a RTLSDR and a bunch of samples (either over time OR with lots of people with the same device)

But to get fine granular data, you need a timestamping SDR. (each parcel of signal data for a quantum of data needs an exact time down to 6-8 significant figures, basically GPS timebase).

Most your cheaper SDRs cant do that.

Stuff like the BladeRF and higher do provide timestamped data.

With synchronized receivers you could do some rudimentary direction finding. Note that synchronizing SDRs is much more achievable if they're physically nearby (e.g. can run a cable between them for a common clock) vs if they're physically distant observers (can't exactly use GPS time for synchronization if you're measuring GPS interference)
> can't exactly use GPS time for synchronization if you're measuring GPS interference

Can other GNSSes (Galileo/BeiDou/GLONASS/etc) give usable timestamps? Seems like it'd be tricky for a jammer to target all of them simultaneously. (Of course, since they'd be on a different band, unless your SDR is wideband enough you'd need two RX heads which gives you potential issues with phase drift between the tuning VCOs even if your sampling is coherent).

Perhaps a sufficiently directional antenna/phased array (for getting an actual satellite signal) as well as an omnidirectional one (for picking up the jamming signal) could get you somewhere...

Or perhaps one could look at computing AoA at each receiver site (using MIMO-y techniques, e.g. Kraken/KerberosSDR) and triangulating based on angles instead, which wouldn't require synchronizing physically-distant sites at all...

The problem definitely seems soluble, though I don't have the technical background to know how realistic that is.

>> Can other GNSS give usable timestamps? Seems like it'd be tricky for a jammer to target all of them

Actually the opposite; GNSS systems are all purposely designed to operate at virtually the same frequency (check out this figure [1]) while cleverly not interfering with each other. There are sub-bands within each constellation too (L1,L2,L5 etc) but it's very easy to pump out wideband noise across all the GNSS bands.

[1] https://www.researchgate.net/figure/The-spectrum-of-current-...

KrakenSDR would do a good job of this, they combine five RTLSDR into a coherent array. The top end of their tuning range is 1766 MHz which would include the 1575 MHz of the GPS L1 signal.

The little five antenna array can even attach on the roof of a car for a handy ground plane. Prob not a good idea to drive with it out there tho.

You could also use a single receiver with a small antenna array (GPS wavelength is around 20 cm) to estimate the angle of arrival of the incoming signals.
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Do aircraft systems really only use GPS and not the full constellation of navigational satellite systems?

Besides GPS, the GNSS currently includes other satellite navigation systems, such as the Russian GLONASS, and may soon include others such as the European Union’s Galileo and China’s Beidou.

https://www.terrisgps.com/gnss-gps-differences-explained/

The linked page already says that it reports on the constellation, not just GPS:

"The map uses are color coded overlay to indicate low (green) to high (red) levels of interference with global navigation satellite systems (GNSS). Often just referred to as GPS, there are actually multiple systems beside the US GPS constellation, such as Russia’s GLONASS, Europe’s Galileo, China’s BeiDou, and others."

Just came here to wonder who came up with the beautiful name of CLOWNASS... er, I mean GLONASS.
GLObalnaya NAvigatsionnaya Sputnikovaya Sistema in Russian.
Like the article states, many people use GPS as a shorthand for GNSS generally. In any case, they're all at similar frequencies, so typically they'll all go out together if there's significant interference.
GLONASS notoriously uses its own band and data format, while following the same basic working principle.
It doesn't matter too much, aircraft don't rely solely on any GNSS for navigation, because they're all susceptible to similar availability issues. Magnetic, inertial, barometric, and land-based radio systems are also used. One or more of those other systems are used as a fallback when GNSS fails.
They use full constellation, in addition to Inertial Nav (INS) -- at least in the US military.
Modern phones use all the available navigation constellations, and have done so for years.

But aviation is much more conservative due to its safety-critical nature. Galileo was only just recently (2023) certified for use in aircraft systems by ICAO:

https://www.esa.int/Applications/Navigation/Galileo/Galileo_...

In the specific case of jamming, it seems unlikely anyone would jam GPS and not also jam the other public GNSS services.

The redundancy of multiple independent GNSS systems is a fine thing for dealing with unintentional failures, of course.

> may soon include others such as (...)

Just for the record, this must have been written ages ago. Today you would rather look up to NavIC joining them as a global system and QZSS operating independently from GPS soon.

Airplanes.Live has an API that you can use to play with this data. https://airplanes.live/api-guide/

Pretty neat! I starting sending data from my ASD-B feeder as well. https://airplanes.live/get-started/

This is really cool since ASDBExchange was bought out by a private equity firm and has since stopped giving out data to cool projects. I see they are being sued for IP theft and a couple other items. Link to Lawsuit in CA is below because I was reading it tonight.

https://www.documentcloud.org/documents/23963235-golden-hamm...

https://www.lacourt.org/casesummary/ui/index.aspx?casetype=c... 23CHCV02662

Is interference the same as jamming?

I am absolutely no expert in this but I can imagine that even natural occurrences can interfere with the GPS.

There are things that will naturally interfere with GPS and they are fairly well known. The FAA provides an expected outage map [1] (a forecast, if you will) for pilots that may need that info. Jamming is an act by humans to intentionally disrupt the GPS signal.

[1] https://sapt.faa.gov/outages.php?outageType=129001450&outage...

And I think the above commenter's point is that ADS-B data does not indicate intentionality.
Could be. I was directly answering "what's the difference?"

It's hard to know intentionality without also knowing where there is expected+natural interference. Of course, when a region is surrounded by persistent GNSS issues and is a known war-zone with large actors, intentionality is fairly reasonably assumed.

The GPS jamming map linked to in the article[1] discusses this somewhat, in the "About the data" box:

    - ADS-B messages include position information from Global Navigation Satellite Systems (GNSS), like GPS, Galileo, GLONASS, BeiDou, etc.
    - It is not possible to directly measure GNSS interference, but we do calculate the NIC (Navigation integrity category) for ADS-B messages.
    - The NIC value encodes the quality and consistency of navigational data received by the aircraft.
    - Poor NIC values alone might indicate a problem with an aircraft’s equipment or unfavorable positioning. However, when observed in multiple aircraft in close proximity during the same time frame, it suggests the presence of a radio signal interfering with normal GNSS operation.
[1] https://www.flightradar24.com/data/gps-jamming
Poland has some big issues with this jamming.

I wonder, how does it influence navigation in mobiles/cars?

Most of the time it is not that strong but few weeks ago my family living north have problems with mobile internet and phones (gps was almost fully dead) for like two days cause of interference from r*ssia.
(comment deleted)
What's going on in that part of western australia? It's a very empty area
> What's going on in that part of western australia? It's a very empty area

You answered your own question. Put 2+2 together.

Hint... https://www.flightradar24.com/apply-for-receiver/

I don't live in that country though
> I don't live in that country though

Exactly.

You don't live there.

Not many people live in the Australian desert.

Conclusion: No data or very limited data

"No data" cells are grey on that map, but western Australia has a couple of red ("high interference") cells.
> but western Australia has a couple of red ("high interference") cells.

Erm mate, have you tried looking at different days ? Those cells you find so suspicious in Australia are not there on other days !

Seriously, given the largely community-based nature of FR24 data I would not expect too much in term of accuracy.

> Erm mate, have you tried looking at different days ? Those cells you find so suspicious in Australia are not there on other days !

That kind of disproves the "no data" hypothesis though, no?

One explanation could be they have a simplistic algorithm like "if uncertainty > (something indicating more than 5 minutes of GNSS-to-INS fallback) on more than 50% of all flights of a day", and there's only one flight per day in that region.

> Seriously, given the largely community-based nature of FR24 data I would not expect too much in term of accuracy.

Flightradar24 data is accurate enough for some commercial entities to rely on it. Also, in case of a lack of ADS-B receiver data we'd also expect a grey square, not a red one, right?

I thought it might have been Square Kilometer Array interference but that's to the north of those spots.
If green or "no data" areas randomly turn red sometimes, I'd expect to see them elsewhere in the world sometimes on different days as well. But I've checked every day that's available and I never see them appear in e.g. that big empty space in eastern Russia.

I don't really see any other evidence that low data areas can turn into red areas when there's no actual interference.

Ok, but let's acknowledge the difference between no data (depicted as no colored cell in the map) and data which reports high interference (depicted as a red cell). In remote western Aus we see a few red cells to the west of a large area of empty cells. So they do have ADS-B receivers there, and at least some of them are reporting a troublesome NIC, and there are enough reports for FR24 to place a colored cell there rather than an empty cell. Why exactly do you think that a red cell comes from no data or very limited data, when the article does not indicate that no data / limited data results in a red cell?
I'm not expert on it, but I suspect that two of them might somehow be related to the Transmit and Receive stations for Australia's JORN (over the horizon radar) that are located in Western Australia near Laverton.

Though if that were the case, I'd probably guess there should be more areas at the other site locations around northern Australia - so that might invalidate my guess.

https://en.wikipedia.org/wiki/Jindalee_Operational_Radar_Net...

https://www.google.com/maps/place/28%C2%B019'02.6%22S+122%C2...

https://www.google.com/maps/place/28%C2%B019'36.3%22S+122%C2...

The choice of cells as a fundamental unit is interesting, I guess it’s better than a color coded gradient map. But this will still suffer from centroid issues.
The data is taken from aircraft [EDIT: not airlines; see traceroute66's comment], so it doesn't give full coverage of the world, but it does include other satellite navigation systems aside from just GPS. Looks like the jammed/interfered areas are:

* A large part of Eastern Europe around Ukraine is missing data, and there are many jammed/interfered areas around it, including the southern coast of the Black Sea and parts of Poland and the Baltic. Part of the Baltic Sea off the coast of Kaliningrad are also jammed/interfered.

* Part of Germany near Berlin, possibly part of the Ukraine-related jamming/interference?

* A large part of the eastern Mediterranean and some of the Middle East around Gaza.

* A small area on the India-Pakistan border near Punjab and Lahore.

* Two medium-sized areas in western Myanmar.

* Two small areas in New Guinea with a gap in the data between them, spanning the Indonesia-Papua New Guinea border.

* Two small areas in western Australia.

* A small area on the US-Mexico border.

* A dot in southern China with some gaps in the data around it near the border with Vietnam.

Ukraine, Gaza, and Myanmar all have major conflicts going on. Other comments have suggested that the US-Mexico interference might be related to drug cartels. The India-Pakistan border is a longstanding point of tension. Not sure what (if anything) is going on in New Guinea and Australia.

The jamming/interference in India-Pakistan, US-Mexico, and China all went away in the last 6 hours -- they're only visible in the 24-hour data.

> The data is taken from airlines

No. It is not.

The data is ADS-B data which is broadcast by aircraft.

FR24 (and other similar services) obtain the data via a community[1], you can take part too[2].

For certain parts of the world, they may have the option to augment the data via commercial services, but that is highly unlikely to be on a global basis.

Conclusion: Missing coverage means no community coverage in that area and no commercial augmentation.

[1] https://www.flightradar24.com/blog/how-we-track-flights-with... [2] https://www.flightradar24.com/apply-for-receiver/

Could you use weather balloons transmitting ADS-B where there are gaps?
Probably better to support a non-commercial ADS-B tracking site. Contribute: https://airplanes.live/get-started/ Gear: https://store.airplanes.live/ API: https://airplanes.live/api-guide/

FR24 is a bit of farce as their blocking and removal of 1000's of aircraft makes the data picture incomplete. Plus it's kinda of a money hungry commercial enterprise. Same reason that Raytheon bought FlightAware and Silversmith Capital Partners via JETNET bought ADSBexchange -DATA = CASH - the later buyout is going to court because they apparently stole IP from the company that built the infrastructure. https://www.documentcloud.org/documents/23963235-golden-hamm... - wild stuff in there!

> Part of Germany near Berlin, possibly part of the Ukraine-related jamming/interference?

Of the four tiles in that area (for March 19th at least), one is entirely in Poland, one is covering the Polish-German border, one is a bit of the German coast around Rügen but mostly the Baltic Sea, and the other is Bornholm (island in the Baltic Sea) and a bit of the Swedish coast.

My guess is, this is part of a larger system to limit Russian military use of the Baltic, and possibly also a single layer of defence against Russian aircraft and missiles targeting Berlin and Copenhagen. Likewise, I would guess that the strip of interference from St Petersburg in the direction of Moscow is a similar single-layer of defence by Russia.

At this resolution, it also looks like the west is interfering with access to St Petersburg and someone (could reasonably be either side) is worried about Kaliningrad, but that image is also also making me think "WTF?" about the Gulf of Riga.

The single tile near Kandalaksha (Russia) suggests something interesting is going on there, but I have no idea what that might be, and there's a non-zero possibility that it's a deliberate red-herring to make western analysts waste time — as an analogy, imagine a troll releasing three greased pigs with the numbers "1", "2", and "4" painted on the side.

This is suspiciously similar to `gpsjam.org`. It's useful, for sure, and it does use readily-available ADS-B data that FR24 (and ADSBExchange) uses anyway, but the data viz is just eerily similar.

Then again, I'm not very GIS/geodesy minded, so maybe hexagons are the best shape that'll tessellate over a sphere easily.

Was this work in any meaningful way inspired by GPSjam? If yes, it'd be nice to have an acknowledgement in there.

I can't say if it's inspired by the site you link, but basing your suspicion on the hexagonal shape is very weak, at best. Also, the data seems to be in different resolutions, and the actual jamming data is quite different just looking at both sites.

I've seen hexagons used for maps and boardgames for years.

If line of sight to the jamming antenna is required to be jammed, why do aircraft not have a downwards shield so that they only receive GPS signal from the sky (satellites) and not from jammers (coming from the bottom hemisphere)? Or is the jamming signal so many orders of magnitudes stronger than the satellites that there's always going to be some gain no matter how good the shield is?

Ok it exists, but shielding is (only) about 20dB looking downwards, which may not be enough: https://safran-navigation-timing.com/product/8230aj-gps-gnss...

I thought GPS signals from space were incredibly weak. Limited power budget + 100km in the sky. Seems trivial for a ground based system to crank up the watts to whatever arbitrary limit they desire.
True, signal per satellite is only around 150-160dBW on earth despite them radiating at 25W. Satellites are ~20000km away. If a jammer is 100 times closer (200km), they need to use only 1/10,000 (1/100^2) the power, so it's very easy to jam sadly.
Two issues to consider:

- GPS positioning is more accurate if the satellites it sees come from a variety of angles (GDOP), so the satellites near the horizon are valuable.

- Aircraft pitch and roll, so a fixed antenna like this would lose precision as it turns to make an approach - just about the worst possible time.

It's difficult to make an antenna with a sharp cutoff to limit the ground vs. above-ground. So, most anti-jammers will use beamforming to cancel out interference in one or more specific directions. So, the null in the antenna moves to follow the interference.

GDOP: https://en.wikipedia.org/wiki/Dilution_of_precision_(navigat...

Does anyone know if the how the ADS-B uncertainty measurements interact with GPS spoofing? Often when you look at these maps you see a donut around Kaliningrad - could it be that there's wide area jamming, and then localized spoofing more directly around Kaliningrad?
I'm a little surprised that Shenzhen doesn't seem to be churning out ITAR-busting anti-jamming systems. The tech is pretty old by now and the market is there.
I'm disappointed in Jamaica I thought they'd be jammin for sure.
I love this feature, especially how they were able to create it from data that they were already getting, but personally my excitement about it is overshadowed by how colorblind unfriendly it is. Considering how many people are colorblind, ~4% of the global population, or roughly 1 out of 25 people, it's remarkable how often designers get this detail wrong.
macOS and iOS have systemwide settings for color blind people. You can remap colors.
Yeah, I love that feature. It's really not helping here though.
If anyone found the above interesting, I wrote a short article mapping plane activity on FlightRadar's 'blocked' list (i.e FlightRadar had agreed to remove the ADBS data from their dataset following probable legal pressure).

https://dfworks.xyz/blog/hnwi-osint-private-jet/

Slightly tangential so feel free to remove if irrelevant

The article was interesting alone, simply for the Google Dork technique explanation. Have not heard the "unusual, yet specifically frequent" search technique described that way previously. Very similar to what's necessary for searching StackExchange and similar, such as "site:https://aviation.stackexchange.com/ tracking private planes"

The Bombardier Global Express 6000 GLT6 result is interesting, as it's a plane with a known large number of military conversions. https://en.wikipedia.org/wiki/Bombardier_Global_Express#Mili...

Known Conversions: GlobalEye, Project Dolphin, Raytheon Sentinel, Saab Swordfish, PAL Aerospace P-6, E-11A, HALOE, PEGASUS, Hava SOJ, CAEW, HADES.

Actually has a tie-in with the article, since the Hava SOJ is an air stand-off jammer configuration for the Turkish region.

Otherwise, if I still worked for the government contracting, I'd probably offer you a job, although you're apparently British, so there might have been citizenship issues.

Apparently people now call using Google's advanced search operators Dorking, neat! I guess I've been dorking for a while.

Most of us know about "site:" since it's extremely handy, but there are a lot more. For some reason I had it in my head that many of the documented operators didn't work properly -- or at least I couldn't get them to work properly the last time I tried to experiment. I'll have to try again.

There was a very recent "bug" in Search where the site: operator stopped working for a little bit and everybody in the OSINT community had a bit of a meltdown - https://www.digitaldigging.org/p/search-alert-google-filetyp...

The date operators from: to: I think have been unsupported for a while and replaced with a dropdown in the UI

filetype: is a fave and has been working for as long as I can remember

AROUND(number) is pretty useful too although I find that might be a bit buggy sometimes

There is a good list here https://www.exploit-db.com/google-hacking-database showing how dorks can be used for pentesting and/or generally finding insecure stuff

Thanks, had no idea there were that many specific operators and combinations of operators.

At least in the last year, looks like "inurl", "intitle", and "intext" have all been getting a lot of use.

Also, a lot of "index of". "db.py", "store", "secret", "ec2 -aws", "mysql inurl:./db/", ect... in combination. Must be a lot of low hanging fruit in the orchard.

Google dorking has been a thing for more than 20 years: https://kit.exposingtheinvisible.org/en/google-dorking.html

(Your comment downplaying someone else's work, while simultaneously showing your lack of historical knowledge on the topic about which you're commenting, based on my specific googling to find the date of coinage, might make you eligible to be "a foolish or inept person as revealed by Google".)

Yep, British for my sins, as a US soldier once described to me, we are your least worst enemy
That's LADD (Limited Aircraft Data Displayed), which requires that aircraft marked as such in the FAA's database to be removed from the official data feeds used by the commercial flight radar sites.

Crowdsourced data isn't subject to LADD, so adsbexchange and other such sites can and do display such aircraft.

For flights within the US, there's also a private address program that allows an ADS-B equipped plane to broadcast an alternate address.

https://www.faa.gov/air_traffic/technology/equipadsb/privacy

Every day is a learning day!
That was interesting, thanks. I liked the co-location analysis idea.
OBS: Does not seem to work in Safari on Mac. Chrome and Firefox works.

Might be use of WebGL which Mac-Safari doesn't support.

I'm on Safari/macOS, and it works perfectly here.
Did you disable WebGL in the Developer menu and forget about it?