Three signals, two services and five second-generation satellites: how NavIC is built

Background

A government backgrounder issued after ISRO launched the NVS-03 navigation satellite on the GSLV-F18 flight from Sriharikota sets out how India's own satellite navigation system is built. NavIC stands for Navigation with Indian Constellation and was earlier called the Indian Regional Navigation Satellite System. It is developed and run by the Indian Space Research Organisation and provides Position, Navigation and Timing services. The constellation was designed with seven satellites, three in geostationary orbit and four in inclined geosynchronous orbit, supported by ground stations working round the clock. Coverage extends over the Indian landmass and about 1,500 km beyond the country's boundary. The legacy signals are L5 and S, and the second-generation NVS series adds the L1 signal. Two services are offered: a Standard Positioning Service open to civilian users and interoperable with GPS, GLONASS, Galileo and BeiDou, and an encrypted Restricted Service for authorised strategic users. The NVS series has five satellites, NVS-01 to NVS-05, and they carry indigenous rubidium atomic clocks.