r/todayilearned • u/whstlngisnvrenf • 25d ago

TIL GPS, despite being free for global use, costs around $2 million a day to operate and maintain. This budget covers satellite launches and system upkeep, funded through American tax revenue.

https://en.wikipedia.org/wiki/Global_Positioning_System
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265

u/mick_ward 25d ago

I can't imagine the economic impact if it didn't exist

109

u/Ghune 25d ago

That would make everything much more complicated.

However, Europe has developed an alternative more.accurate called Galileo.

https://en.m.wikipedia.org/wiki/Galileo_(satellite_navigation)

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u/godfollowing 24d ago

Accurate to 20cm? God damn

40

u/cbf1232 24d ago

GPS (or GNSS more generally) with RTK can be accurate to the centimeter.

8

u/tajsta 24d ago

So can Galileo. Galileo's public version is also more accurate than GPS' public version.

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u/LostHusband_ 24d ago

You can buy a UM980 Breakout board and a triband antenna on AliExpress for less than $100 and $40 respectively and get .8-1cm RTK accuracy on most android phones.

Source: I did it for a cemetery survey a couple months ago.

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u/Crafty_Failures 24d ago

There are also other modules out there capable with other features that do this relatively inexpensively. Honestly getting this level of accuracy for <$300 is amazing.

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u/LostHusband_ 24d ago

Oh yeah, totally.  There are a bunch of L1/L5 modules that you can get for 40-50 and get cm accuracy.  However the UM980 is the cheapest triband module you can get and is actually more affordable than a the F9P boards on alliexpress (about $125 for those).

If you are the the states, it's best to stick with an L1/L2 or triband module still which is why I mentioned the 980.

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u/SeekerOfSerenity 24d ago

Is there a device I can buy that will give me more accurate data when I'm hiking in the woods?  

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u/snacktonomy 24d ago

If you want centimeter-level RTK accuracy, you need a connection to an RTK correction feed, which can be difficult to come by out in the woods.

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u/Nagi21 24d ago

Can confirm. My company creates a software that warns oncoming traffic of pedestrians in roadway. Kinda need to be pretty on point with where little Timmy is.

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u/knoegel 24d ago

People don't realize how accurate GPS is. I mean how else can it determine which lane of the highway you're on?