Where Am I ?

[Paul Dale]

(06-09-2016 06:07 PM)Dave Shaffer Wrote:  And, if that's still not good enough (i.e. 10 centimeters claimed in the article), you could use interferometric GPS. That would give you one cm or better accuracy - in 3D, not just 2D. This is how much surveying is done nowadays.

Differential GPS isn't this accurate. The usual rule of thumb is GPS puts you in a room (10-20m), differential at a desk (1ish meters) and RTK right there (1-2cm).

RTK truly is an amazing piece of mathematics -- finding the diophantine solutions to the simultaneous equations counting the number of wavelengths to each satellite in view and using that to get your position. All this is possible because you've got a base station with an exact known position.


Pauli