Definition
Equipment, software, or signal services that improve the accuracy, integrity, continuity, or availability of the GPS Standard Positioning Service (SPS) so it can be used for more demanding navigation tasks. Augmentation systems include the Wide Area Augmentation System (WAAS), which corrects GPS signals using a network of ground reference stations and geostationary satellites; the Local Area Augmentation System (LAAS), which provides high-precision corrections near an airport for precision approaches; and onboard Receiver Autonomous Integrity Monitoring (RAIM), which checks GPS signal integrity using the receiver itself.
Plain English
Extra equipment or signals that make basic GPS more accurate and trustworthy enough for serious navigation, including instrument approaches.
Context Anchor
Seen in discussions of WAAS-capable GPS receivers, satellite navigation, and instrument approaches that depend on improved GPS accuracy.
Derivation
Augment comes from the Latin augere, meaning to increase or add to. The systems do exactly that — they add corrections and integrity checks on top of the basic GPS signal.
Why Pilots Care
It enables precision approaches with lower minimums at airports without expensive ground-based equipment, improving access and safety.
Intuition Check
Do not read “augments” as “replaces.” Here it means the system adds corrections and checks to the basic GPS signal so the receiver can give better guidance.
Example Sentence 1
The aircraft's WAAS-equipped receiver is hardware which augments the GPS Standard Positioning Service, allowing it to fly LPV approaches.
Example Sentence 2
Before departure the pilot confirmed that the ware which augments the GPS standard positioning service was available along the route.