The IRNSS, also known as Navigation Indian Constellation (NavIC), is an independent regional navigation satellite system developed by India.

IRNSS is a regional GNSS owned and operated by the Government of India.
It is designed as an autonomous system to provide accurate position information service to assist in the navigation of ships in the Indian Ocean waters, as well as air traffic.
It could replace the US GPS system in the Indian Ocean, up to approximately 1500 kilometres from the Indian boundary.

Space segment

Current Satellites

The IRNSS constellation consists of 8 satellites, one of which is suffering from a partial failure.

  • IRNSS-1A no longer has a working atomic clock.
  • IRNSS-1H failed to launch.
SatelliteDate LaunchedOrbit ConfigurationStatus
IRNSS-1A1 July 2013Geosynchronous (IGSO) / 55°E, 29° inclined orbitPartial Failure
IRNSS-1B4 April 2014Geosynchronous (IGSO) / 55°E, 29° inclined orbitOperational
IRNSS-1C16 October 2014Geostationary (GEO) / 83°E, 5° inclined orbitOperational
IRNSS-1D28 March 2015Geosynchronous (IGSO) / 111.75°E, 31° inclined orbitOperational
IRNSS-1E20 January 2016Geosynchronous (IGSO) / 111.75°E, 29° inclined orbitOperational
IRNSS-1F10 March 2016Geostationary (GEO) / 32.5°E, 5° inclined orbitOperational
IRNSS-1G28 April 2016Geostationary (GEO) / 129.5°E, 5.1° inclined orbitOperational
IRNSS-1H31 August 2017Launch Failed
IRNSS-1I12 April 2018Geosynchronous (IGSO) / 55°E, 29° inclined orbitOperational
Table showing the current satellites, including one partial failure and a failed to launch.

Planned Satellites

The following additional Satellites are planned and will be launched within the future.

NameOrbit TypeOrbit AngleRelease Date
IRNSS-1JGeosynchronous (IGSO),42° inclined orbitPlanned
IRNSS-1KGeosynchronous (IGSO)42° inclined orbitPlanned
IRNSS-1LGeosynchronous (IGSO)42° inclined orbitPlanned
IRNSS-1MGeosynchronous (IGSO)42° inclined orbitPlanned
IRNSS-1NGeosynchronous (IGSO)42° inclined orbitPlanned
Planned IRNSS satellites.

Ground segment

The IRNSS Ground Segment communicates with the satellite constellations which includes sending/receiving positioning messages and route updates, as well as providing maintenance.

Ground segment layout

  • IRNSS Spacecraft Control Facility (IRSCF)
  • ISRO Navigation Centre (INC)
  • IRNSS Range and Integrity Monitoring Stations (IRIMS)
  • Laser Ranging Stations
  • IRNSS Network Timing Centre (IRNWT)
  • IRNSS CDMA Ranging Stations (IRCDR)
  • IRNSS Data Communications Network(IRDCN)

User Segment

The user segment is comprised of GPS receivers and antennas which are used to receive signals from the IRNSS.

The GPS devices are also capable of working interoperable between the various GNSS.
The plan is to to broadcast the time difference between the IRNSS time and the time of the other GNSS constellations to enable users to take advantage of the signals available to them.


The system was designed to provide positioning accuracy which does not exceed 10m throughout the Indian land region.
In addition to this, accuracy within the 1,500 ocean border was intended to be better than 20m.

In the year 2017, The Space Applications Centre advised that NavIC will provide standard positioning service to all users with a accuracy of positioning up to 5 m. 

In comparison, GPS which is owned and operated by America had a position accuracy of 20-30m.

Another difference is that unlike GPS which operates on a single L-Band, NavIC has dual frequency support of the S & L bands.
As a result, when low frequency signal travels through the atmosphere, the velocity changes due to atmospheric disturbances.
US relies on the atmospheric model to assess frequency error and it has to update this model from time to time to assess the exact error.
In India’s case, the actual delay is assessed by measuring the difference in delay of dual frequency (S and L bands).
Therefore, NavIC is not reliant on any model to find the frequency error and is more accurate than GPS


IRNSS can be used in a multlitude of ways, some of the applications include:

  • Marine, Aerial and Land Navigation
  • Management of disasters
  • Fleet Management & Vehicle Tracking
  • Aerial Tracking
  • Mobile Phone Navigation
  • Precise Timing
  • Geo spatial and Mapping data capture
  • Terrestrial navigation aid for hikers and travelers
  • Augmented Reality

The Future of NavIC

The NavIC constellation was launched primarily to provide accurate positioning and timing services in real time, with a 10-20 metres range of precision.
It was designed to be used over India’s Land and Ocean Territory.

Considering the NavIC system currently services it’s intended regions, along with the number of global GNSS that are already in service, ISRO have no plans now, nor in the future to make NavIC a global navigation system.