The Indian Regional Navigational Satellite System (IRNSS) is an autonomous regional GPS-based satellite navigation system being developed by the Indian Space Research Organisation (ISRO) and it would be under the total control of the Govt of India. The IRNSS’s R & D programme was approved in May 2006. Total project cost is Rs16 billion and the project is due for completion by 2012. The IRNSS will comprise a constellation of seven GPS navigation satellites placed in geostationary orbit that will provide an absolute position accuracy of better than 10 metres throughout India and within a region extending approximately 2,000km around India.
On the other hand, the GPS Aided Geo Augmented Navigation or GPS and Geo Augmented Navigation system (GAGAN) is a planned implementation of a regional satellite-based augmentation system (SBAS) by the Govt of India to improve the accuracy of a GNSS receiver by providing reference signals. The Rs7.74 billion project is being implemented in three phases since 2008 by the Airports Authority of India (AAI) with the help of ISRO. The goal is to provide GPS-based navigation cues for all phases of flight over the Indian airspace and in the adjoining regional area. It is applicable to safety-to-life operations, and meets the performance requirements of international civil aviation regulatory bodies. The final, operational phase of GAGAN is due for completion by May 2011.—Prasun K. Sengupta