It's functionally equivalent to an RTK base station (the configuration script I'm using is even called "RTKbase"[0]), but it's being used for researching GPS-based soil moisture retrieval[1]. Basically the GPS signal bounces off the ground and causes an interference pattern that changes based on the wetness of the soil.

There is actually a permanent survey grade GNSS reciever about 200 m away from the u-blox receiver. But the geography around it (too hilly) means it doesn't work for soil moisture retrieval.

[0] https://github.com/Stefal/rtkbase/ [1] https://gnssrefl.readthedocs.io/en/latest/pages/understand.h...