July 18, 2012: The Airports Authority of India and the Indian Space Research Organisation (ISRO) have jointly commenced the process of Final System Acceptance Test (FSAT) of GAGAN – (GPS Aided Geo Augmented Navigation) – India’s own value addition to GPS based navigation for aircraft.
The objective of Final System Acceptance Test is to evaluate the system performance and its critical parameters in the integrated live environment using the satellite signals and ground based systems on integrity, accuracy, continuity and availability for aviation use.
A network of precisely surveyed 15 ground reference stations INRES (INdian Reference Stations) is strategically positioned across the country to collect GPS satellite data. Using this information, the master control centre INMCC (INdian Master Control Centre) generates messages to correct any signal errors. These correction messages are then up-linked through INLUS (INdian Land Uplink Station) and broadcast through GEO stationary Indian communication satellites, which can be to received by onboard aircraft/User receivers using the same frequency as GPS.
The intense test involves using the data collected from all the 15 Ground Reference stations located across the country and satellite signals to provide necessary augmentations to the GPS standard positioning service (SPS) navigation signal.
The successful completion of Final System Acceptance Test will
pave way for further process of system certification by Regulatory authorities and formal commissioning by June 2013
GAGAN – Project brief
GAGAN the Indian SBAS (Satellite Bases Augmentation System) which is a prestigious project jointly undertaken by Airports Authority of India and ISRO in accordance with ICAO,s strategic plan to achieve smooth transition to Satellite based Navigation and seamless Air traffic management across the continents.
GAGAN is designed to provide the additional accuracy, availability, and integrity necessary to enable users to rely on GPS for all phases of flight, from en route through approach for all qualified airports within the GAGAN service volume.
GAGAN will also provide the capability for increased accuracy in position reporting, thereby making possible high-quality Air Traffic Management (ATM).
In addition, GAGAN will provide benefits beyond aviation to all modes of transportation, including maritime, highways, railroads and public services such as defense services, security agencies, and disaster recovery management by aiding in search and rescue to locate the disaster zone accurately, telecom industry and personal users of position location applications.
India is only the fourth country in the world, after USA, JAPAN and Europe to take up the challenge of establishing the regional SBAS that will redefine the navigation over India and adjacent regions. The footprint of GAGAN will cover huge area beyond Indian Territory, from Africa to Australia and can support seamless navigation across the Globe. The system is also interoperable with other such systems of WAAS of USA, EGNOSS of Europe and MSAT of Japan.
India being located in the Equatorial Region, GAGAN is the first system in the world that is being developed to serve the equatorial anomaly region with its unique IONO algorithm.
Tech brief from Wikipedia: http://en.wikipedia.org/wiki/GPS-aided_geo-augmented_navigation