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Curious, how do you measure your own gps “accuracy”? Also, is “jamming” a precision reduction (seems improbable given how I think gps works) or a signal strength reduction in this case?
Why is Moscow almost constantly red?
Curious, how do you measure your own gps “accuracy”? Also, is “jamming” a precision reduction (seems improbable given how I think gps works) or a signal strength reduction in this case?
This paper describes in more detail some experiments using a GPS jammer and flying an aircraft around Edwards Air Force Base with ADS-B and what happens to the position reporting: https://web.stanford.edu/group/scpnt/gpslab/pubs/papers/Liu_...
This is fascinating. Really cool to see a map of GPS signals on Earth and the site looks really good, too. Love the colors and interface! Awesome :) Can anyone narrate any of the jammed signals? Like for instance what would be jamming in the ocean between Tripoli and Benghazi? Or what would be jamming around San Antonio, TX?
I know the stories behind some of the regions, or at least some hypotheses. Interference in the U.S. is almost always the result of military testing or training. If you check against another map (Google maps, or skyvector.com/globe.adsbexchange.com to see sectional charts) you'll see that the interference region is usually centered on or close to a military base or Military Operations Area. There are often FAA notice…
https://www.cnet.com/culture/truck-driver-has-gps-jammer-acc...
I haven't followed their progress and was really surprised to see globe view, 3D terrain and custom projections landing in v2.
Curious, how do you measure your own gps “accuracy”? Also, is “jamming” a precision reduction (seems improbable given how I think gps works) or a signal strength reduction in this case?
Because GPS is way cool. First, there is the official site: https://www.gps.gov/systems/gps/performance/accuracy/ I am far from being an expert, but being a flying nerd, that's what I can tell you:
The more satellites in sight you have access to, the cooler stuff you can do with GPS. Minimum to establish 2D (on globe projection 2D) location is 3 sats, minimum for altitude is 4 sats. There are mathematical simulations you can do to see if, and when, a given aircraft will have access to 4 sats (or more), called RAIM: https://www.mygdc.com/new/static/usermanuals/web_help/RAIM_P...
Now, things get even better if you use 4+ sats, or sats from different constellations (I am not sure how mature is cross-constellation data validation, however, so let's pretend 1 constellation for now). With 5 sats, the receiver can calculate the position even more precisely, determine the level of URE, etc. You can even detect that one source is unreliable, and discard it (effectively falling back to 4 sats). With even more sats you can (theoretically) do cool data analysis, where you can determine those factors even more precisely.
Now, add the inertial factors. Many passenger have either in-software (history of previous positions) or in-hardware (think accelerometers, magnetometers) inertial data sources. A sophisticated flight management software (FMS) can cross-corelate the inertial data with GNSS data and determine when the latter becomes unreliable.
All of those measurements and factors can subsequently be reported via ADS-B or ACARS, to help with fleet management, and general predictive maintenance. While aviation technology might sometimes look way out of date at a first glance, the modern airplanes have some really cool technology hiding in it.
Why is Moscow almost constantly red?
This is fascinating. Really cool to see a map of GPS signals on Earth and the site looks really good, too. Love the colors and interface! Awesome :) Can anyone narrate any of the jammed signals? Like for instance what would be jamming in the ocean between Tripoli and Benghazi? Or what would be jamming around San Antonio, TX?
I know the stories behind some of the regions, or at least some hypotheses. Interference in the U.S. is almost always the result of military testing or training. If you check against another map (Google maps, or skyvector.com/globe.adsbexchange.com to see sectional charts) you'll see that the interference region is usually centered on or close to a military base or Military Operations Area. There are often FAA notice…
This is fascinating. Really cool to see a map of GPS signals on Earth and the site looks really good, too. Love the colors and interface! Awesome :) Can anyone narrate any of the jammed signals? Like for instance what would be jamming in the ocean between Tripoli and Benghazi? Or what would be jamming around San Antonio, TX?
I know the stories behind some of the regions, or at least some hypotheses. Interference in the U.S. is almost always the result of military testing or training. If you check against another map (Google maps, or skyvector.com/globe.adsbexchange.com to see sectional charts) you'll see that the interference region is usually centered on or close to a military base or Military Operations Area. There are often FAA notice…
Cool project, thanks! A bit nitpicking: > In Europe, Poland, Romania, Lithuania, Latvia, Kaliningrad, and Finland sometimes show presumed jamming activity, depending on how active Russia is. The wording here is confusing, it seems to imply that Kaliningrad is a country, which it is not (it's a Russian exclave, as the author mentions in one of the HN comments).
Would it sound similar like saying hurricane about to hit Cuba, Florida and Dominican Republic. This does not imply that Florida is a country is just more precise location definition than saying USA. Same here with Kaliningrad as part of Russia.