GPSJam: Daily maps of possible GPS interference (opens in new tab)

Would you be interested in handing it off to a maintainer owning it in a 501c3 as a public good? If not, do you want to continue to run it as a non profit public good with donations? I am willing to donate, just curious what the costs look like, and am a huge fan of projects like this (sensor networks/fabrics).

How do you know that a RA has happened? You infer it from the flight paths?

Also, I'd just add ads and some recurrent donations and see how it goes - it looks to me that you're the perfect person to run projects like these. It would make no sense if money was the only problem that stops you.

To pile on about what this actually shows, further the data is sourced from ADSB Exchange so there's only data in areas where there are sufficient participants, and skews coverage towards Europe and North America

https://map.adsbexchange.com/mlat-map/

You're saying aircraft are reporting position based on their INS? That seems… weird. I've also been told the opposite, that ADS-B navigation accuracy is always reported based on GNSS, not INS. What's your source?

I hope this doesn't confuse the issue, because I don't think it's actually related to what you're talking about, but recently there have been reports of inertial nav systems being "corrupted", essentially, by spoofed GNSS. The hypothesis is that the INS/IRS is corrected using spoofed GNSS data after which the INS/IRS reports bad info: https://ops.group/blog/faa-warning-navigation-failures/

It should be easy to correct for - only count aircraft that actually report good navigation accuracy sometimes.

That would explains why Ukraine went from mostly green around 20 February 2022, to ‘no data’ several days later.

Jamming is not only near the Kremlin, but also in large parts of Хамовники, near places like Лужники, ЦСКА (because of the mall & stadium), Лубянка, Сити and so on.

Since this data is reported by airplanes I wonder if they experience more jamming because the jamming signals distribute easier upwards than through the jungle of buildings in the city.

It actually shows "no data" over Ukraine.

Ukraine enforces no flight zone because of the war. Therefore there is no data.

It is protection against drones

GLONASS supports time setting too.

Mapbox GL JS https://docs.mapbox.com/mapbox-gl-js/guides/

It's probably military testing and/or training. See my earlier comment about the Laughlin and Randolph military operating areas–Casamigos Ranch is under the Laughlin MOA.

Yes, a lot of GPS receivers provide RAIM or jamming indication, if they detect signals they're not expecting. Gpsjam just isn't set up to accept such data.

I think Galmon.eu may collect it along with all the other receiver-status data, but it isn't exposed in the main dashboard. You'd have to figure out how to extract it from the data, and I don't think anyone's done that yet, but we're in #galileo on OFTC IRC.

The main problem with this approach is that it's hyper-local. Ground stations aren't moving so they don't cover a very broad area, and they're not evenly distributed or even necessarily in interesting locations. Quite the contrary; regimes that employ GPS jamming are likely also hostile to citizens reporting on same.

If you take your own measurements you can do a lot more than what this site is doing, but with the disadvantage that you have to take your own measurements. For example, you could:

1. directly observe signal integrity with your own GPS receiver

2. compare the location your receiver reports with the actual known location

3. compare the location your receiver reports on GPS with the location a different GNSS network reports.

Murcia–San Javier is a Spanish Air Force base.

I agree that the visualization is not optimal. I wish I was a better visual designer!

(major assumption) That's more than likely the position of the USS Gerald R. Ford (CVN-78).

Its support planes are in the area [1], and it was sighted on Sep 28 near Italy [2], and if I understand it correctly, has been tasked to this area.

1 - https://twitter.com/wipljw/status/1712780646530118125

2 - https://www.marinevesseltraffic.com/vessels/USS-Gerald-R.-Fo...

The invasion and subsequent occupation must've been pretty annoying as well !

Snarky jokes aside, in my experience GPS works okay in Cyprus, so the jamming must be localised somehow.

interference does not necessarily impact people on the ground – these readings are from thousands of feet in the air and are hence exposed to a lot more signals.

You probably need to be in the line of sight of the interfering device, so it has much less coverage on the ground level.

There are no legal GPS jammers in the USA. In fact, the one of two things that will get the FCC on you really bad is to mess with GPS or Cell Phone signals.

For Example, US Prisons want to jam Cell Phones but the FCC says no way.

The map uses the H3 tiling system, and the cells displayed are resolution 4. Sometimes for specific cases I look at higher resolutions. For example, I believe this map I did during the still-unexplained Dallas-Fort Worth major interference event of 2022 uses resolution 6: https://twitter.com/lemonodor/status/1582403839004508160

The caveats of that tweet still apply to higher resolutions: Specifically that you start to see the effects of individual aircraft, which can be harder to interpret.

Poor ADSB coverage there?

You need to have one nerdy geek to record the data per ~500 mile circle of the globe.

Thats why ocean coverage is bad too.

I'm not sure. It's very unusual to see even low levels of potential interference in that area. Looking at detailed stats using the history feature of GPSJAM PRO, I'd say it's likely there's a real effect that is having an impact on a significant percentage of aircraft in that area. It's true it can be tricky to figure out exactly what it is having an impact.

Data:

  Date        % w/ poss. interference    # Good    # Bad
  ---------   -----------------------    -------   -----
  2023-10-04  2.82%                      1172      33
  2023-10-05  0.00%                      1204      0
  2023-10-06  2.55%                      1253      32
  2023-10-07  0.42%                      1184      5
  2023-10-08  0.00%                      1261      0
  2023-10-09  4.03%                      1216      49
  2023-10-10  2.21%                      1178      26
  2023-10-11  0.00%                      1176      0
  2023-10-12  0.00%                      1203      0

"# Good" is the number of distinct aircraft that flew through that hex that never reported low accuracy with their GNSS. "# Bad" is the number of distinct aircraft that at some point during their flight reported good accuracy with their GNSS, but some time after that, including while flying through that hex, reported low accuracy. I would say that based on the number of aircraft showing up as Bad, and the fact that it's just that hex seeing this effect, it's likely to be showing a real effect.

My list of the most common things that make an aircraft report low GNSS accuracy:

1. Intentional GPS jamming.

2. Unintentional GPS interference.

3. Aerobatics that cause the aircraft's GPS antennae to be masked from satellites by the body of the aircraft.

4. On-board equipment issues.

I think the data suggests it's not #4. #3 is typically seen in military operating areas (MOAs) in the U.S.; I don't know if there might be fighters practicing in the skies west of London.

Edit to add: FWIW I've gotten one report from a person in the yellow hex that they weren't able to get a GPS fix. That's all I know.

> What's going on near london?

As others have said, more likely dodgy methodology by gpsjam than anything sinister.

For example:

    - As well as being an active airfield, Heathrow also houses a small number of maintenance bases (e.g. BA have one, United are currently upgrading an ex-Virgin one etc.). I'm not familiar with aircraft maintenance, but I suppose there could easily be scope for RF signals related to test procedures to be leaky and be picked up by geeks.

    - There is also Farnborough.  Whilst Farnborough is predominantly a GA (General Aviation, i.e.  private jet) airfield, it is also on of the many homes of QinetiQ in the UK.  QinetiQ being a defence contractor.  So again, one could speculate about leaky test signals.

There's Windsor Castle near the green area of the center (Windsor Grey Park). And some related military installations close by. Easy to see why it would be jammed...

Does seem strange, there aren't any NOTAMs mentioning it that I can see.

People always think we're jamming GPS near the border, but all those yellow and red hexes are in the Laughlin and Randolph military operating areas (MOAs). It's much more likely to either be military testing/training involving systems that cause GPS interference, or jet fighter training where aircraft maneuver so hard their GPS antennas are masked from satellites by the body of the aircraft.

Map showing the possible interference overlaid on an FAA sectional chart showing the MOAs: https://i.imgur.com/vieGhgN.png

I would hope that nobody uses this particular map for actual navigation!

And how many people looking at maps on the internet really perform (globe-scale) navigation where it would even matter?

Getting a sense for distances and/or proportions is arguably the most common use case, with “a sense for the precise bearing” a distant follower.