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You make me wonder, are these systems programmed to fall back to Galileo EU, Russian Or Chinese (mainland) GNSS at all? Should we fall back to systems controlle

You make me wonder, are these systems programmed to fall back to Galileo EU, Russian Or Chinese (mainland) GNSS at all? Should we fall back to systems controlled by other countries?

throw0101a 2y ago
> You make me wonder, are these systems programmed to fall back to Galileo EU, Russian Or Chinese (mainland) GNSS at all? In the US, per FCC rules, it is not officially allowed to listen to other GNSS frequencies as they are not licensed: > The Federal Communications Commission (FCC) rules require licensing of non-federal receive-only equipment operating with foreign satellite systems, including receive-only earth stations operating with non-U.S. licensed radionavigation-satellite service (RNSS) satellites. * https://www.gps.gov/spectrum/foreign/ https://www.gps.gov/spectrum/foreign/ The FCC allowed Galileo use in 2018: * https://www.fcc.gov/document/fcc-approves-galileo-global-navigation-system-0 https://www.fcc.gov/document/fcc-approves-galileo-global-nav... I think the reasoning is that if it is not "officially sanctioned" then if there's interference with those signals it's not the FCC's problem. By allowing it they'll take noise on those frequencies more seriously in rules and enforcement.
- thanksgiving 2y ago
  I don't think I understand what allowed means in this context because on my OnePlus Nord phone, I have an app called GPS Test which shows me that I have so many GPS, so many GLONASS, and so many Galileo in view. Strange thing is there is no Chinese GNSS in view. (I was on a short trip to Bali recently and iirc I did see Chinese GNSS on the app while there so I think the app and phone hardware is capable of picking up Chinese GNSS?).
  - throw0101d 2y ago
    > I don't think I understand what allowed means in this context because on my OnePlus Nord phone, I have an app called GPS Test which shows me that I have so many GPS, so many GLONASS, and so many Galileo in view. That app may simply be reporting the presence of signals, but the geolocation functions and APIs may not actually use those signals in their calculations. And if they are actually processing the signals, then they are breaking FCC regulations: * https://selectcommitteeontheccp.house.gov/media/press-releases/gallagher-presses-fcc-us-cell-phones-and-devices-using-chinese-russian-gps https://selectcommitteeontheccp.house.gov/media/press-releas... Legally they could get their FCC certification pulled and not be allowed to be sold in the US if they are doing that.
nradov 2y ago
FAA certified avionics won't fall back from GPS to foreign GNSS constellations for authorized flight operations. If GPS is degraded then pilots have to fall back to older navigation methods. Those foreign constellations mostly all operate on similar frequency bands so if GPS is being jammed in a certain area then the other systems will likely also be impacted.
minetest2048 2y ago
In the context of time synchronization, my gut feeling is no, as you can't guarantee that the atomic clocks on other GNSS tick at the same time as GPS. Even if they have the same frequency. I can't find any benchmarks though that measures this

You make me wonder, are these systems programmed to fall back to Galileo EU, Russian Or Chinese (mainland) GNSS at all? Should we fall back to systems controlled by other countries?

throw0101a 2y ago

> You make me wonder, are these systems programmed to fall back to Galileo EU, Russian Or Chinese (mainland) GNSS at all? In the US, per FCC rules, it is not officially allowed to listen to other GNSS frequencies as they are not licensed: > The Federal Communications Commission (FCC) rules require licensing of non-federal receive-only equipment operating with foreign satellite systems, including receive-only earth stations operating with non-U.S. licensed radionavigation-satellite service (RNSS) satellites. * https://www.gps.gov/spectrum/foreign/ https://www.gps.gov/spectrum/foreign/ The FCC allowed Galileo use in 2018: * https://www.fcc.gov/document/fcc-approves-galileo-global-navigation-system-0 https://www.fcc.gov/document/fcc-approves-galileo-global-nav... I think the reasoning is that if it is not "officially sanctioned" then if there's interference with those signals it's not the FCC's problem. By allowing it they'll take noise on those frequencies more seriously in rules and enforcement.

thanksgiving 2y ago
I don't think I understand what allowed means in this context because on my OnePlus Nord phone, I have an app called GPS Test which shows me that I have so many GPS, so many GLONASS, and so many Galileo in view. Strange thing is there is no Chinese GNSS in view. (I was on a short trip to Bali recently and iirc I did see Chinese GNSS on the app while there so I think the app and phone hardware is capable of picking up Chinese GNSS?).
- throw0101d 2y ago
  > I don't think I understand what allowed means in this context because on my OnePlus Nord phone, I have an app called GPS Test which shows me that I have so many GPS, so many GLONASS, and so many Galileo in view. That app may simply be reporting the presence of signals, but the geolocation functions and APIs may not actually use those signals in their calculations. And if they are actually processing the signals, then they are breaking FCC regulations: * https://selectcommitteeontheccp.house.gov/media/press-releases/gallagher-presses-fcc-us-cell-phones-and-devices-using-chinese-russian-gps https://selectcommitteeontheccp.house.gov/media/press-releas... Legally they could get their FCC certification pulled and not be allowed to be sold in the US if they are doing that.

nradov 2y ago

FAA certified avionics won't fall back from GPS to foreign GNSS constellations for authorized flight operations. If GPS is degraded then pilots have to fall back to older navigation methods. Those foreign constellations mostly all operate on similar frequency bands so if GPS is being jammed in a certain area then the other systems will likely also be impacted.

minetest2048 2y ago

In the context of time synchronization, my gut feeling is no, as you can't guarantee that the atomic clocks on other GNSS tick at the same time as GPS. Even if they have the same frequency. I can't find any benchmarks though that measures this