GAGAN
ISRO and the Airports Authority of India (AAI) collaborated on the GAGAN project, implementing a Satellite Based Augmentation System (SBAS) for Indian airspace. GAGAN’s primary goal is to establish a certified satellite-based augmentation system specifically for safety-critical applications. The system’s functional performance and operational criteria are aligned with international standards. Additionally, GAGAN is designed to be interoperable with other global SBAS systems such as US-WAAS, European EGNOS, and Japanese MSAS.
The GAGAN Final System Acceptance Test (FSAT) concluded on July 16th-17th, 2012. Subsequently, the GSAT-8 satellite, housing the GAGAN Payload, was integrated with Indian Land Uplink station-1 (INLUS) in Bangalore, enabling GAGAN Signal in Space (SIS) availability since December 15, 2011. Moreover, GSAT-10 satellite integration with Indian Land Uplink station-2 in Bangalore led to the availability of the second GAGAN SIS from April 2013. The backup Delhi INLUS became operational in March 2013 and is linked to GSAT-8
The Key elements of GAGAN are: 15 Indian Reference Stations (INRESs)
- 2 Indian Master Control Centers (INMCCs)
- 3 Indian Lank Uplink Stations (INLUSs)
- 4 chains of networks (OFC and VSAT)
- 3 GEO satellites with GAGAN payloads

The GPS Aided Geo Augmented Navigation (GAGAN) system has a range of applications across various sectors due to its ability to provide accurate and reliable satellite-based navigation, positioning, and timing services.
Some key applications of GAGAN include:
- GAGAN significantly benefits the aviation sector by providing precise navigation and approach guidance for aircraft, enhancing safety during takeoff, landing, and en-route phases. It aids in reducing congestion and optimizing air traffic management.
- GAGAN supports maritime navigation by offering accurate positioning information for ships, vessels, and boats, improving safety and efficiency in coastal and open-water navigation.
- In land transportation, GAGAN assists in optimizing routes, improving logistics, and enhancing the efficiency of vehicle navigation systems for cars, trucks, buses, and railways.
- GAGAN aids in accurate surveying, mapping, and geospatial applications. It facilitates precise measurements, land surveying, and cartographic activities for infrastructure development and urban planning.
- GAGAN’s accurate positioning data supports precision farming techniques. It enables farmers to optimize irrigation, crop monitoring, and machinery guidance, leading to increased agricultural productivity.
- During emergencies and natural disasters, GAGAN assists in search and rescue operations by providing accurate location information, aiding in timely response and relief efforts.
- GAGAN contributes to telecommunication networks by providing precise timing information essential for synchronization in various systems and applications.
- GAGAN supports scientific research, geodetic studies, and environmental monitoring by offering accurate positioning and timing data for scientific experiments and observations.
- Location-Based Services (LBS): GAGAN enhances location-based services for smartphones, tablets, and other devices, enabling a wide array of location-aware applications for users.
- Defense and Security Applications: GAGAN has applications in defense and security sectors, providing a secure and reliable navigation system for military operations and strategic planning.
- GAGAN utilizes a constellation of geostationary satellites along with a network of ground-based stations to enhance GPS signals over the Indian airspace and neighboring regions
- GAGAN comprises Indian Reference Stations (INRESs) distributed across the region. These ground-based stations track GPS signals and gather data on errors and corrections
- The INRESs collect raw GPS data and transmit it to the Indian Master Control Center (INMCC). Here, the collected data undergoes rigorous analysis and processing
- Corrections and integrity data are generated at the INMCC based on the analysis of GPS data from reference stations. These augmentation messages contain information to refine GPS signals and enhance their accuracy
- The corrected augmentation messages are sent to the geostationary satellites, such as GSAT (Geostationary Satellite) series, via Indian Land Uplink Stations (INLUSs)
- The geostationary satellites broadcast the enhanced GPS signals containing augmentation data, known as Signal-in-Space (SIS), to GPS/GAGAN-enabled receivers on the ground
- GPS/GAGAN receivers receive signals from both GPS and GAGAN satellites. They process the combined signals, utilizing the augmentation data to refine GPS positioning and navigation information
- GAGAN’s augmentation messages correct GPS signal errors caused by atmospheric disturbances and other factors, improving the accuracy, reliability, and integrity of the positioning information provided to users
- GAGAN offers safety-critical services designed specifically for aviation, ensuring the accuracy and reliability of navigation information for aircraft during critical phases of flight
Download Our App Now!