Indian Regional Navigation Satellite System (IRNSS), with an operational name of NavIC (acronym for Navigation with Indian Constellation; also, '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 around it, with plans for further extension up to with 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, 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 , with the cost of the ground segment being , each satellite costing and the PSLV-XL version rocket costing around . The planned seven rockets would have involved an outlay of around .
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 .
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.
Clock failure In September 2008, it was reported that SpectraTime received a contract worth to supply Rubidium Space Clocks to ISRO for the IRNSS programme.
In 2017, it was announced that all three SpectraTime supplied rubidium atomic clocks on board IRNSS-1A had failed, mirroring similar failures in the European Union's Galileo constellation. The first failure occurred in July 2016, followed soon after by the two other clocks on IRNSS-1A. This rendered the satellite non-functional and required replacement. ISRO reported it had replaced the atomic clocks in the two standby satellites, IRNSS-1H and IRNSS-1I in June 2017. The subsequent launch of IRNSS-1H, as a replacement for IRNSS-1A, was unsuccessful when PSLV-C39 mission failed on 31 August 2017. The second standby satellite, IRNSS-1I, was successfully placed into orbit on 12 April 2018.
In July 2017, it was reported that two more clocks in the navigational system had also started showing signs of abnormality, thereby taking the total number of failed clocks to five, in May 2018 a failure of a further 4 clocks was reported, taking the count to 9 of the 24 in orbit.
As a precaution to extend the operational life of navigation satellite, ISRO is running only one rubidium atomic clock instead of two in the remaining satellites.
only four first generation satellites were capable of providing navigation services which is the minimum number required for service to remain operational.
only four satellites IRNSS-1B, IRNSS-1F, IRNSS-1I and NVS-01 were capable of providing navigation services.
In July 2025, while responding to a query through Right to Information Act, the ISRO revealed that five IRNSS satellites are completely defunct, with all of their three clocks having failed. Additionally, one satellite has only one functional clock and only two satellites are fully functional.
On 10 March 2026, with IRNSS-1F clock failure marking completion of its 10 year mission life reduced the satellite network to only three operational satellites sending position data, below minimum number of satellites needed for accurate position data. It will be a part of five satellites out of the eight remaining functional satellites, being used to provide one way broadcast messaging services from thereon. India had launched a total of eleven NavIC satellites at that point.
Indian Atomic clock In order to reduce the dependency on imported frequency standards ISRO's Space Applications Centre (SAC), Ahmedabad had been working on domestically designed and developed Rubidium based atomic clocks. To overcome the clock failures on first generation navigation satellites and its subsequent impact on NavIC's position, navigation, and timing services, these new clocks would supplement the imported atomic clocks in next generation of navigation satellites.
On 5 July 2017, ISRO and Israel Space Agency (ISA) signed an Memorandum of Understanding to collaborate on space qualifying a Rubidium Standard based on AccuBeat model AR133A and to test it on an ISRO satellite.
The clocks are utilised by the NVS series of satellites. As part of the Times Dissemination Project, which is overseen by the Ministry of Consumer Affairs, Food, and Public Distribution, NavIC will take the position of GPS as the reference time provider at the National Physical Laboratory of India from 2025.
Microprocessor The SPARC V8 ISA compatible AJIT microprocessor for robotics and industrial applications was created in 2018 by IIT Bombay. The Ministry of Electronics and Information Technology, IIT Bombay, and Powai Labs, a private firm from Mumbai, provided funding for the project. Initially produced by Semi-Conductor Laboratory utilizing 180nm process, commercial production using 65nm and 45nm are planned. AJIT operates at clock speeds between 70 and 120 MHz and can execute one instruction every clock cycle.
It includes a memory management unit that stores and retrieves data from memory, as well as an arithmetic logic unit that performs simple arithmetic and logical operations. Additionally, there is a floating point unit that can effectively manage computations involving non-integer quantities. A hardware debugger unit is used to monitor and control the microprocessor in order to program it. The Society for Applied Microwave Electronics Engineering & Research will incorporate AJIT in the receivers being developed for NavIC.
NavIC chip In accordance with the range requirements for NavIC for both military and commercial applications, Defence Research and Development Organisation, through the Technology Development Fund scheme, has commissioned Accord Software and Systems, to build a tailored and flexible IRNSS Network Timing system domestically. Using NavIC data, the receiver chip will obtain and distribute Indian time for navigation. India currently depends on the US for this service.
In 2020, Qualcomm launched four Snapdragon 4G chipsets and one 5G chipset with support for NavIC. NavIC is planned to be available for civilian use in mobile devices, after Qualcomm and ISRO signed an agreement. To increase compatibility with existing hardware, ISRO will add L1 band support. For strategic application, Long Code support is also coming.
On December 7, 2023, Qualcomm revealed that select chipset platforms will enable NavIC L1 signals. The Qualcomm location suite, supports up to seven satellite constellations simultaneously and allows for faster Time to First Fix (TTFF) position acquisition for enhanced location-based services. It also makes use of all of NavIC's L1 and L5 signals for precise positioning. In the second half of 2024, Qualcomm chipset platforms will add further support for the NavIC L1 signals, and in the first half of 2025, commercial products that support the NavIC L1 signals should be available for sale.
Timeline In April 2010, it was reported that India plans to start launching satellites by the end of 2011, at a rate of one satellite every six months. This would have made NavIC functional by 2015. But the program was delayed, and India also launched 3 new satellites to supplement this.