GAGAN Satellite-Based Augmentation System

GAGAN stands for GPS Aided GEO Augmented Navigation. It is India’s indigenous Satellite-Based Augmentation System (SBAS) developed jointly by the Indian Space Research Organisation (ISRO) and the Airports Authority of India (AAI). The system has been operational since 2015 and supports satellite navigation for aircraft operations in Indian airspace.

Satellite-Based Augmentation System

A Satellite-Based Augmentation System is a regional navigation system that improves the accuracy, reliability, and integrity of Global Positioning System signals. SBAS uses ground reference stations, master control centres, uplink stations, and geostationary satellites to correct navigation errors and provide precision approach services.

GAGAN Network and Space Segment

GAGAN operates through 15 Indian Reference Stations, two Master Control Centres, three Land Uplink Stations, four communication networks, and three geostationary satellites. The satellites used for GAGAN payloads are GSAT-8, GSAT-10, and GSAT-15.

Aviation Applications and LPV Procedures

In June 2026, the Directorate General of Civil Aviation conducted India’s first satellite-based landing approach on a commercial jet aircraft, an IndiGo A320, at Udaipur Airport using GAGAN technology. As of May 2026, the Airports Authority of India had published 23 Localizer Performance with Vertical Guidance (LPV) approach procedures, with a target of more than 40 by the end of 2026.

Important Facts for Exams

• India is one of the few countries with an operational SBAS.
• India was the first country to have an SBAS certified for the equatorial region.
• LPV stands for Localizer Performance with Vertical Guidance.
• GAGAN is used beyond aviation in maritime navigation, railways, road transport, disaster management, telecommunications, defence, and geospatial mapping.

Integration with NavIC

Efforts were underway in June 2026 to integrate GAGAN with NavIC, which stands for Navigation with Indian Constellation. NavIC is India’s regional satellite navigation system and is used to build a more sovereign positioning architecture.