GPS Position Error (DOP)
Overall positioning error is the geometry factor (dilution of precision) multiplied by the per-satellite ranging error.
Formula
Variables
Example
GDOP 2.5, UERE 4 m: σ_pos ≈ 10 m
Did You Know?
Widely spread satellites give a low DOP and a sharp fix; satellites bunched together give a high DOP, so the same ranging accuracy can yield a far worse position.
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