• elmicha@feddit.org
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    2 days ago

    20 years ago we had only GPS, and it already was accurate to 10 or 20 meters.

    • zqps@sh.itjust.works
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      2 days ago

      GPS is actually far more accurate than that. There is deterministic jitter introduced to make civilian use cases precise to only a few meters, but military equipment has the algorithm to subtract that jitter and achieve precision measured in centimeters.

      Anyway, that statement is highly misleading. They were comparing to previous inertial navigation systems, not GPS navigation.

      • Logi@lemmy.world
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        7 hours ago

        Didn’t they turn all that jitter off like 15 years ago?

        Edit: I ran a little experiment and zig-zagged up a bit of hill on the bike this morning and the GPS/Galileo/Glonass unit resolved it easily. However, it didn’t quite agree where the road was.

        Map showing wiggly cycling track

        The road, was pretty narrow. The road

    • Deebster@infosec.pub
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      2 days ago

      Is that true globally? I seem to remember that some ocean areas wouldn’t have as many satellites visible as e.g. polar orbits don’t visit all of the globe.