Making regular GPS ultra-precise
11 comments
·October 7, 2025Havoc
Why don’t cities have ground beacons for this?
Much cheaper than satellites and would be guaranteed to see heavy use
myself248
Some places have free RTK networks their citizens can use. Michigan's department of transportation, for instance, runs a CORS network that anyone can request access to. (At least as far as I can tell. The signup form doesn't ask for affiliation or payment.) It's just distributed over the internet, the assumption being that you probably have internet access already.
One of these days I'll figure out how to set up a free NTRIP caster on my Galmon station so it can do double-duty. The trick then is advertising and discovery.
It would be lovely to have, say, a standard wifi SSID or a standard LORA channel that your local corrections network would broadcast on. That way you could have a large number of client devices not each needing their own internet access SIM card or whatever. I wonder if the corrections stream would fit into an FM RDS payload or something.
Trouble is, there's so much money in the L-band corrections services, and so little money in replacing them for free...
Oh, yeah, the cryptocurrency folks have weighed in, there's a thing called "goodnet" which appears to be microtransactions in exchange for NTRIP streams over some medium. I haven't looked further into it.
eqvinox
That's kinda what RTK does, you have a ground station and transfer correction data for the visible satellites from it to your GNSS receiver. It doesn't transmit a GNSS signal itself but functionally the effect is vaguely comparable to a "satellite on the ground", without interfering on the actual signals.
Tepix
Another option to get more precise positioning is to switch from GPS to Galileo.
Galileo generally offers better civilian accuracy than GPS because it uses modern signal structures with better resistance to multipath and interference and provides dual-frequency signals (E1 + E5) to all users, which mitigates ionospheric errors.
ktosobcy
most software now uses multiple GNSS at the same time?
mavhc
Don't cars also measure their wheel movements to increase location accuracy?
Nothing in this article is new, and the problem with RTK has always been the (unpaid) availability of reference stations. Good on them for trying to make a package of it, but maybe this "news" site could've used a bit less unchecked enthusiasm.
Also, RTK is the opposite of "regular" GPS, it's generally considered a "special" usage mode of GPS.
And discussing urban canyons with no mention of QZSS?