IRNSS
| Country/ies of origin |
 India
|
|---|---|
| Operator(s) | ISRO |
| Type | Military, Commercial |
| Status | Operational |
| Coverage | Regional (up to 1,500 km from borders) |
| Accuracy | 10 m (public) 0.1 m (encrypted) |
| Constellation size | |
| Total satellites | 7 |
| Satellites in orbit | 6 (1 redundant) |
| First launch | 1 July 2013 |
| Last launch | 28 April 2016 12:50 pm IST |
| Total launches | 7 (All Successful) |
| Orbital characteristics | |
| Regime(s) | High Earth |
| Orbital height | 36,000 km (22,000 mi) |
| Other details | |
| Cost | $212 million |
The Indian Regional Navigation Satellite System (IRNSS) with an operational name of NAVIC ("sailor" or "navigator" in Sanskrit, Hindi and many other Indian languages, which also stands for NAVigation with Indian Constellation) is an autonomous regional satellite navigation system, that provides accurate real-time positioning and timing services. It covers India and a region extending 1,500 km (930 mi) around it, with plans for further extension. The system at-present consist of a constellation of 7 satellites, with two additional satellites on ground as stand-by.
The constellation is already in orbit and system is expected to be operational from early 2018 after a system check. NAVIC will provide two levels of service, the 'standard positioning service' will be open for civilian use, and a 'restricted service' (an encrypted one) for authorized users (including military).
There are plans to expand NavIC system by increasing constellation size from 7 to 11.
The system was developed partly because access to foreign government-controlled global navigation satellite systems is not guaranteed in hostile situations, as happened to the Indian military in 1999 when it was dependent on the American Global Positioning System (GPS) during the Kargil War. The Indian government approved the project in May 2006.
As part of the project, the Indian Space Research Organisation (ISRO) opened a new satellite navigation center within the campus of ISRO Deep Space Network (DSN) at Byalalu, in Karnataka on 28 May 2013. A network of 21 ranging stations located across the country will provide data for the orbital determination of the satellites and monitoring of the navigation signal.
A goal of complete Indian control has been stated, with the space segment, ground segment and user receivers all being built in India. Its location in low latitudes facilitates a coverage with low-inclination satellites. Three satellites will be in geostationary orbit over the Indian Ocean. Missile targeting could be an important military application for the constellation.
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