GAGAN
Also called: GPS Aided GEO Augmented Navigation · Topic: Remote Sensing, GIS and GNSS · NCERT: Beyond NCERT
Meaning
GAGAN (GPS Aided GEO Augmented Navigation) is a system built by ISRO and the Airports Authority of India. Plain GPS signals carry small errors. GAGAN works out these errors over India and sends corrections through satellites in geostationary orbit, which stay above one spot on the equator. Aircraft use the corrected positions to guide their approach to airports. It was certified in 2015, the first such system serving the equatorial region.
Example
A plane approaching an Indian airport uses GAGAN-corrected GPS to follow its approach path accurately. This makes landings safer, even where there are few landing aids on the ground.
Don't confuse with
- NavIC: NavIC is India's own satellite navigation system with its own satellites. GAGAN does not give positions by itself; it only corrects GPS.
- CORS: CORS gives centimetre-level corrections from ground stations for surveying, not for aviation.
Related concepts
- Global navigation satellite system
- Global Positioning System
- Trilateration
- NavIC
- NVS series satellites
- Continuously Operating Reference Stations