Navigation with Indian Constellation (NavIC)
✦ To meet the positioning, navigation and timing requirements of the nation, ISRO has established a regional navigation satellite system called Navigation with Indian Constellation (NavIC).
✦ NavIC was erstwhile known as Indian Regional Navigation Satellite System (IRNSS).
✦ NavIC is designed with a constellation of 7 satellites and a network of ground stations operating 24 x 7.
✦ Three satellites of the constellation are placed in geostationary orbit, at 32.5°E, 83°E and 129.5°E respectively.
✦ Four satellites are placed in inclined geosynchronous orbit with equatorial crossing of 55°E and 111.75°E respectively, with inclination of 29° (two satellites in each plane).
✦ NavIC offers two services: Standard Position Service (SPS) for civilian users and Restricted Service (RS) for strategic users.
✦ These two services are provided in both L5 (1176.45 MHz) and S band (2498.028 MHz). NavIC coverage area includes India and a region up to 1500 km beyond Indian boundary.
✦ NavIC was first approved in 2006 but became operational only by 2018.
✦ L1 frequency is the most commonly used frequency in GPS.