GAGAN (Space & Defence Sectors)
GAGAN (Space & Defence Sectors)
Why In News:
GAGAN (GPS Aided GEO Augmented Navigation) has been highlighted as a key component of India’s digital and technological infrastructure.
Source: PIB Today, 1 July 2026, 'GAGAN: PIB Backgrounder'.
What is GAGAN?
GAGAN is a Space Based Augmentation System (SBAS), jointly developed by the Indian Space Research Organisation (ISRO) and the Airports Authority of India (AAI), that improves the accuracy, integrity, and availability of the standard GPS signal.
How It Works
Ground segment: A network of 15 Indian Reference Stations (INRES) spread across India collect GPS satellite data.
Control segment: The Indian Master Control Centre (INMCC) processes this data and generates correction messages for errors caused by ionospheric disturbances, timing, and satellite orbit.
Space segment: Correction messages are uplinked through Indian Land Uplink Stations (INLUS) to geostationary satellites (GSAT-8, GSAT-10, GSAT-15), which broadcast the corrected signal to GAGAN-enabled receivers.
Applications Beyond Aviation
Disaster management alerts through the GAGAN Message Service; railway signalling; road and highway lane guidance; precision agriculture; and navigation on inland waterways.
Key Facts for Prelims
India was the first country in the Asia-Pacific region to develop an indigenous SBAS.
GAGAN has been mandatory for all aircraft registered in India since 1 July 2021; the first GAGAN-guided landing was by an IndiGo ATR-72 at Kishangarh airport on 29 April 2022.
GAGAN is distinct from NavIC (Navigation with Indian Constellation), India's own independent regional satellite navigation system, which does not depend on the US GPS constellation.