[Retracted] Mining Geological Environment Monitoring and Real-Time Transmission Based on Internet of Things Technology

Table 2

The corresponding relationship between GDOP value and positioning accuracy grade.

GDOP value	1-2	2-3	3–6	6–9	9–20	More than 20
Positional accuracy	Ideal	Excellent	Good	Moderate	Mediocre	Bad
Grade	Best	Excellent	Good	Moderate	Qualified	Bad