3.4.10. Accuracy of GNSS observations

Try these first

1. 1.

   What does GNSS stand for?

   Hint

   Think broader than just GPS.

2. 2.

   What is the typical accuracy of standalone GPS units?

   Hint

   Think about basic GPS functions.

3. 3.

   What is the expected accuracy in local surveys using high-precision GNSS?

   • 10 cm
   • 1 mm
   • 0.1-4 mm

   Hint

   Think about how close measurements can be in smaller areas.

4. 4.

   True or False: Atmospheric delays affect GNSS signal travel time.

   • True
   • False

   Hint

   Consider how weather might impact satellite signals.

5. 5.

   If a GNSS receiver measures a distance of 1500m in an area with severe multipath effects, how might this distance likely differ from an accurate measurement taken in an open area?

   Hint

   Consider how reflections can alter the true distance.

6. 6.

   Given that atmospheric delays can add up to 4m of error to GNSS measurements, what strategies might a surveyor use to minimize this error in a large field project?

   Hint

   Think about the tools a surveyor has to improve accuracy.