Table 1 Uncertainty sources (95% confidence level) for position, determined from GPS, and the total uncertainty, assuming the normal distribution of the uncertainty sources, high degrees of freedom and a coverage factor, k, of 2
From: Overview of legal traceability of GPS positioning in Australia
Uncertainty source | Position uncertainty horizontal (mm) | Position uncertainty vertical (mm) |
|---|---|---|
Type A—Experimental error | 2 | 6 |
Type B—Antenna phase centre | 3 | 10 |
Type B—Monument stability | 1–20 | 1–40 |
Type B—Other sources including un-modelled crustal loading, satellite orbit variations, atmosphere, tectonics, signal multi-path | 6 | 10 |
Total | 7–21 | 15–43 |