The GPS aided geo augmented navigation or GPS and geo-augmented navigation system (GAGAN) is an implementation of a regional satellite-based augmentation system (SBAS) by the Indian government.
It is a system to improve the accuracy of a GNSS receiver by providing reference signals. The AAI's efforts towards implementation of operational SBAS can be viewed as the first step towards introduction of modern communication, navigation, surveillance/Air Traffic Management system over Indian airspace.
The project has established 15 Indian Reference Stations, 3 Indian Navigation Land Uplink Stations, 3 Indian Mission Control Centers, and installation of all associated software and communication links.[4] It will be able to help pilots to navigate in the Indian airspace by an accuracy of 3 m. This will be helpful for landing aircraft in tough weather and terrain like Mangalore and Leh airports.
