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So a localized outage can in fact affect the entire planet. This has also implications in disaster scenarios.
Not sure how applicable this is for GPS.
Earlier quoted context omitted.
Galileo has like a dozen different signals and I believe that most of them aren't broadcasting yet. I'm not sure which of those signals is supposed to give 1cm accuracy, but it could be one of the encrypted signals. Another consideration is that the 1cm accuracy would only be possible with fancy DGPS or RTK setups. 1cm accuracy is doable with GPS today, but unless you're a farmer or land surveyor you probably don't o…
I suspect this is an extremely naive question, but why would one signal give a 1cm accuracy and another one not? Shouldn't the satellite just tell you its trajectory + identification info so you can calculate where you are based on that? Or perhaps by signal do you mean the physical electromagnetic properties (frequency etc.) are unsuitable for high accuracy, rather than the actual information content it's supposed t…
The most interesting part of the whole write up is that it sheds light on how dependent of the base stations these constellations are. I used to think that, other than sending orbital corrections and the occasional fixes, the constellation would run itself. Apparently this is not the case. So a localized outage can in fact affect the entire planet. This has also implications in disaster scenarios. Not sure how applic…
Earlier quoted context omitted.
I suspect this is an extremely naive question, but why would one signal give a 1cm accuracy and another one not? Shouldn't the satellite just tell you its trajectory + identification info so you can calculate where you are based on that? Or perhaps by signal do you mean the physical electromagnetic properties (frequency etc.) are unsuitable for high accuracy, rather than the actual information content it's supposed t…
To get good precision you need to remove the effect of electrons in the ionosphere. These basically change the index of refraction and therefore the propagation speed of the radio waves. The delayed signal makes your receiver think it is further away from the satellite than it actually is. One way to estimate this delay (instead of relying e.g. on the correction signal of a differential-GPS base station close to you)…
Maybe instead of 24*7 work, some manager thought it was 24/7 work, and sent everyone home.
Earlier quoted context omitted.
This is a bit of the interesting aspect to this failure. Official channels have overall been pretty weak on details on what all happened in this error. Most public knowledge of what happened has been gleaned from the signals coming off the satellites themselves which anyone can see. This live data combined with understandings of how the system should work is most of the public knowledge of what has been going on. I d…
Exactly. And the galmon network already does that. (It should really be renamed gnssmon at this point, it's far outgrown its Galileo-watching roots.) You can run a station yourself if you have a Ublox 8- or 9-series receiver.
Is 1cm accuracy part of Galileo system already operational? If so, why our phones and other devices cannot utilise it yet?
Because of that allocation, the FCC cannot guarantee that Galileo HAS receivers will not be interfered with.
The most interesting part of the whole write up is that it sheds light on how dependent of the base stations these constellations are. I used to think that, other than sending orbital corrections and the occasional fixes, the constellation would run itself. Apparently this is not the case. So a localized outage can in fact affect the entire planet. This has also implications in disaster scenarios. Not sure how applic…
Of course, if the ground station failure was a soft failure, and instead of ceasing to upload, it began uploading incorrect data, the GPS location results would be arbitrarily bad to unusable. It's not clear to me whether the Galileo outage was because of a hard ground station failure or a soft one. But given that one of the contributing factors was that the backup system was not online, it would indicate to me that this was a hard failure that GPS would have been able to correct.
author here - if anyone has any questions or remarks, let me know!
Thanks for writing this. The title doesn't mention that Galileo is a Global Navigation System (GPS).
Saying Galileo is a GPS is like saying Target is a Walmart.