Galileo navigation system facing service degradation or loss of signal

https://insidegnss.com/galileo-interruptus/

by leemailll • 7 years ago

103 33 7 years ago

Fun fact, the Galileo system was designed to be more accurate and difficult to jam than the civilian GPS but after the US saw this a potential threat and considered shooting down the satellites in case of a global conflict, the design was switched to a frequency they could easily jam.[1]

[1] https://en.wikipedia.org/wiki/Galileo_(satellite_navigation)...

jki275• 7 years ago

What makes a frequency easy to jam?

wil421• 7 years ago

The frequency initially chosen for Galileo would have made it impossible for the US to block the Galileo signals without also interfering with its own GPS signals.

Not an answer to your question but it was more about being able to jam GNSS while still being able to use GPS.

dewey• 7 years ago

At issue is the U.S. Department of Defense (DoD) desire to be able to jam other radionavigation signals in a theater of operation so as to provide an edge to allied users of military GPS receivers. This "selective denial" capability would be complicated by the presence of an encrypted PRS signal atop the M-code bands, because the U.S. could not jam the PRS without jamming its own signals.

There's some more info here: https://arquivo.pt/wayback/20090628141907/http://findarticle...

tolqen• 7 years ago

That frequency not being the same as the one used by the US’s own GNSS system enabling them to block it without blocking their own service.

nabla92• 7 years ago

That's not what the link you provided says.

The new Galileo frequency is just as hard to jam as the original frequency. The change was made to allow blocking or jamming of one GNSS without affecting the other.

GuB-42• 7 years ago

It seems like the situation was resolved in the best way possible. It is not that Galileo was harder to jam, but that jamming Galileo would also mean jamming their own GPS. So they settled on using different frequencies, which means you can jam one without jamming the other, and vice versa.

Also, possibly as a result of these negotiations, the US said they will stop using selective availability for GPS.

For me, that's the best solution for everyone, at least in times of peace. And in times of war, well, all bets are off anyways.

the-dude3• 7 years ago

Just a coincidence.

jimmaswell• 7 years ago

I think someone is refusing to return a slab to someone.

wybiral6• 7 years ago

The link seems under heavy stress right now but here's an archive of it: https://web.archive.org/web/20190713001332/https://insidegns...

buboard• 7 years ago

Ok first slack, twitter, facebook, and now this? I told you it’s aliens

the-dude3• 7 years ago

Google, Cloudflare, Azure, Stripe.

wybiral6• 7 years ago

* slides on tin foil helmet *

Well, yeah, they've been trying to distract people away from the whole Area 51 thing.

neals• 7 years ago

We'll find out soon though, if it's really Aliens, as we storm the desert.

f_50C137y• 7 years ago

Wow! I've been having some issues navigating whilst driving with Google Maps and Strava for running these last few days. I assumed the issue was my smartphone, but I am curious to know if the issue was, in fact, due to the Galileo issues listed.

reportingsjr• 7 years ago

If you're using a phone for those services then almost certainly not. Almost all phones support multiple GNSS (GPS, galileo, GLONASS, etc) so one going down shouldn't cause issues.

6d6b73• 7 years ago

All of the satellites? What could possible cause all of them to fail at the same time? It's not hardware because they weren't all switched at the same time. Software?

the-dude3• 7 years ago

Wrong config push.

wybiral6• 7 years ago

Yeah, bad regex.

sambull• 7 years ago

Common frequency. Someones blocking them?

marcinzm• 7 years ago

That could cause a regional outage but this isn't being described as such, seems global.

nabla92• 7 years ago

Satellites are just part of the GNSS system. There are multiple control centers and network of sensor , uplink, telemetry, tracking and control stations around the world.

The problem is most likely on the ground. When GNSS satellites are not getting updated data from the ground stations their accuracy starts to degrade.

Rebelgecko• 7 years ago

From the updated version of the linked article, looks like the ground station that keeps the clocks synced up is down or not giving the sats accurate date

jdnier• 7 years ago

Sounds kind of like the recent global Cloudflare outage. That outage started with a regex (WAF rule) being pushed out that immediately exhibited pathological backtracking behavior and "caused CPUs to become exhausted on every CPU core that handles HTTP/HTTPS traffic on the Cloudflare network worldwide."

https://blog.cloudflare.com/details-of-the-cloudflare-outage...

PeterStuer• 7 years ago

You can find the current system status and its history here https://www.gsc-europa.eu/system-status/Constellation-Inform...

diggan• 7 years ago

Since the website itself is not working, here is gsc-europa's own dashboard:

https://www.gsc-europa.eu/system-status/Constellation-Inform...

This is the specific incident: https://www.gsc-europa.eu/notice-advisory-to-galileo-users-n...

Seems to have started 2019-07-11 14:45 (UTC) so a couple of days ago.

Apparently, they used to have failures with the clocks (https://en.wikipedia.org/wiki/Galileo_(satellite_navigation)...) so might be something similar.

wybiral6• 7 years ago

Apparently, they used to have failures with the clocks

That would explain if a few of them were weird, but the report said "SATELLITE AFFECTED: ALL" which would be quite a coincidence if each clock on each satellite failed at the same time.

wybiral6• 7 years ago

The recent update on the report seems to point to an Italian facility that relates to timing though:

Guenter Hein, Professor Emeritus of Excellence at the University FAF Munich told us, “As far as I know, it is a problem of the PTF [Precise Timing Facility] in Italy – time has an impact on the whole constellation!”

wybiral6• 7 years ago

There was a recent study [1] looking into the economic impact of GPS in the US which "estimate that the loss of GPS service would have a $1 billion per-day impact". Not sure how that translates to Galileo GNSS.

[1] https://www.rti.org/sites/default/files/gps_finalreport.pdf

riffraff• 7 years ago

IIUC, the analysis assumes other systems would also be disrupted, as modern devices support multiple location services (gps, galileo, glonass).

So there isn't really a case of GPS failing while Galileo works and viceversa, it's just "everything fails" vs "something works".

jakegold• 7 years ago

The EU's stance is that Galileo is a neutral technology, available to all countries and everyone. At first, EU officials did not want to change their original plans for Galileo, but have since reached the compromise that Galileo is to use a different frequency. This allows the blocking or jamming of either GNSS without affecting the other.

Galileo navigation system facing service degradation or loss of signal

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