Navigation General · Electronic Nav — DGPS/WAAS
Differential GPS (DGPS) and WAAS improve position accuracy by:
- AAdding more receivers aboard
- BBroadcasting correction data computed at reference stations of known position✓ Correct
- CIncreasing the boat's speed
- DTurning off other electronics
Explanation
Fixed reference stations at precisely known positions compute the GPS error and broadcast corrections. The receiver applies them to refine its fix from meters of error to a few meters or better. WAAS is a satellite-based augmentation system serving North America.
Authority: Bowditch
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