4 ms·
Just because one uses GPS to measure position does not mean one is calculating position in WGS84, the GPS native geodetic datum. For instance many survey instr
by jhayward 8y ago
Just because one uses GPS to measure position does not mean one is calculating position in WGS84, the GPS native geodetic datum.
For instance many survey instruments use Differential GPS to obtain a more precise location by using corrections from a receiver at a well-established survey mark. When using DGPS the coordinate system becomes that of the reference mark, not the GPS system.
So I think the question is relevant, and takes note of the context in which ground motion is studied.
- JoeAltmaier 8y agoBut that ground point is located by GPS as well, which translates the more-precise location relative to the ground point right back to the WGS84 frame
- jhayward 8y agoNo, the ground point is most often registered in either a continental or regional plate datum.
- JoeAltmaier 8y ago'Most often'? By whom? These things are in use in the 100's of thousands in agriculture now. Such base stations record their ground point by GPS location.