Indian Regional Navigation Satellite System (IRNSS), with an operational name of NavIC (acronym for Navigation with Indian Constellation; also, nāvik 'sailor' or 'navigator' in Indian languages), is an autonomous regional satellite navigation system that provides accurate real-time positioning, velocity and timing (PVT) services. It covers India and a region extending 1,500 km (930 mi) around it, with plans for further extension up to 3,000 km (1,900 mi) with 10–20 m (33–66 ft) position accuracy and 40ns time accuracy. An extended service area lies between the primary service area and a rectangle area enclosed by the 30th parallel south to the 50th parallel north and the 30th meridian east to the 130th meridian east, 1,500–6,000 km (930–3,730 mi) beyond borders where some of the NavIC satellites are visible but the position is not always computable with assured accuracy.
Background The system was developed partly because access to foreign global navigation satellite systems is not guaranteed in hostile situations, as happened to the Indian military in 1999 when the United States denied an Indian request for Global Positioning System (GPS) data for the Kargil region, which would have provided vital information. The Indian government approved the project in May 2006. The NavIC offers two levels of service, standard positioning service (SPS), which will be open for civilian use and is interoperable with GNSS, and a restricted service (RS), an encrypted channel for authorized users including the military, in L1 (1575.42 MHz, in use since the second generation), L5 (1176.45 MHz) and S Band (2498.028 MHz). The first generation (IRNSS series) of the satellite network was designed for 7 satellites with three atomic clocks each, including IRNSS-1A, IRNSS-1B, IRNSS-1C, IRNSS-1D, IRNSS-1E, IRNSS-1F and IRNSS-1G serving as initial set of satellites, and replacement satellites, IRNSS-1H failing to reach orbit, followed by the successful launch of IRNSS-1I. However, multiple failure of on-board atomic clocks across satellites prompted ISRO to adopt indigenous atomic clocks, developed by the Space Application Centre, Ahmedabad, for its second generation of NVS satellites. The NVS series, including NVS-01, NVS-02, NVS-03, NVS-04 and NVS-05, would employ a mix of imported and indigenous atomic clocks as well as an increased operational lifetime from 10 to 12 years. However, as of March 2026, only three satellites were capable of providing PVT service — IRNSS-1B, IRNSS-1I and NVS-01 — due to the failure of atomic clocks of IRNSS satellites, failure of NVS-02 to reach orbit and launch delay of the second generation satellites. This is below the minimum number of four satellites required for an accurate position. Meanwhile, five satellites — IRNSS-1A, IRNSS-1C, IRNSS-1E, IRNSS-1F and IRNSS-1G — are being used for one-way broadcast messaging service after their on-board atomic clocks failed. IRNSS-1D has been decommissioned while two other satellites, IRNSS-1H and NVS-02, failed to reach desired orbit. ISRO is planning to launch NVS-03, NVS-04 and NVS-05 by September 2027. NavIC-based trackers are compulsory on commercial vehicles in India, and some consumer mobile phones with support for it have been available since the first half of 2020.
Developments
First Generation (IRNSS series) As part of the project, the Indian Space Research Organisation (ISRO) opened a new satellite navigation centre within the campus of ISRO Deep Space Network (DSN) at Byalalu, 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 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. The total cost of the project was expected to be ₹1,420 crore (US$147 million), with the cost of the ground segment being ₹300 crore (US$31 million), each satellite costing ₹150 crore (US$16 million) and the PSLV-XL version rocket costing around ₹130 crore (US$13 million). The planned seven rockets would have involved an outlay of around ₹910 crore (US$94 million). The necessity for two replacement satellites, and PSLV-XL launches, has altered the original budget, with the Comptroller and Auditor General of India reporting costs (as of March 2017) of ₹2,246 crore (US$233 million). India's Department of Space in their 12th Five Year Plan (FYP) (2012–17) stated increasing the number of satellites in the constellation from 7 to 11 to extend coverage. These additional four satellites will be made during 12th FYP and will be launched in the beginning of 13th FYP (2018–23) in geosynchronous orbit of 42° inclination. Also, the development of space-qualified Indian made atomic clocks was initiated, along with a study and development initiative for an all optical atomic clock (ultra stable for IRNSS and deep space communication). The NavIC Signal in Space ICD was released for evaluation in September 2014. From 1 April 2019, use of AIS 140 compliant NavIC-based vehicle tracking systems were made compulsory for all commercial vehicles in India. In December 2019, the United States Congress consented to designate NaVIC as one of their allied navigational satellite systems along with Galileo (Europe) and QZSS (Japan). The approval was as a part of National Defense Authorization Act 2020. The proposal was put forward by United States Secretary of Defense in consultation with Director of National Intelligence.
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