IRNSS / NavIC: India’s Own Navigation Satellite System

Think of a map app that works only if another country allows it. India decided not to depend on that. NavIC is the result.

What does NavIC stand for?

• NavIC stands for Navigation with Indian Constellation.
• IRNSS is the earlier name, Indian Regional Navigation Satellite System. ISRO says NavIC was erstwhile known as IRNSS.
• The name was given by the Prime Minister on 28 April 2016. A PTI report says he called it NavIC, meaning boatman.
• The job is position, navigation and timing for India and a region up to 1,500 km beyond its boundary.

Why did India want its own system?

ThePrint reports that India asked for GPS data on enemy positions in Kargil in 1999. The request was denied. That pushed the government towards a home-grown system.

The point is self-reliance. India wanted a navigation system that it controls.

When did the project begin?

The Union Cabinet approved it on 9 May 2006. The approved cost was Rs 1,420 crore. The first satellite flew in 2013.

NavIC is a regional system. It is designed with seven satellites and a ground network that works day and night.

Where do the seven satellites sit?

• Three are in geostationary orbit, at 32.5°E, 83°E and 129.5°E.
• Four are in inclined geosynchronous orbit. Their equator crossings are at 55°E and 111.75°E, with two satellites in each plane.
• The tilt of those four orbits is 29 degrees.

How high are they?

PIB gave the heights in August 2022. NavIC satellites are at about 36,000 km. GPS satellites are in medium Earth orbit at about 20,000 km.

What does the ground network do?

It has a control centre and a precise timing facility. It also has range and integrity monitoring stations and two-way ranging stations. ISRO lists these as parts of the NavIC ground network.

NavIC gives two services. Each is sent on two frequency bands.

Who gets which service?

• Standard Positioning Service (SPS) is for civilian users.
• Restricted Service (RS) is for strategic users.
• Both services are sent in the L5 band at 1176.45 MHz and the S band at 2498.028 MHz.

How accurate is it?

ISRO says position accuracy is better than 20 m over the primary service area. Its services page gives timing accuracy as better than 50 ns. Its NVS-02 page says 40 ns.

PIB adds that two frequencies help. A dual-frequency receiver can correct errors caused by the atmosphere.

What is the new L1 signal?

A new civilian signal is being added in the L1 band at 1575.42 MHz. ISRO says all satellites from 2023 onwards will send SPS signals in L1, L5 and S.

Does NavIC work with other systems?

Yes. ISRO says NavIC SPS signals work with GPS, GLONASS, Galileo and BeiDou. The International Maritime Organization has recognised NavIC as part of the worldwide radio navigation system for ships.

The first generation is the IRNSS-1 series. Every satellite in it weighed 1,425 kg at lift-off.

When did each one launch?

• IRNSS-1A flew on PSLV-C22 in July 2013. It was the first.
• IRNSS-1B, 1C and 1D flew in April 2014, October 2014 and March 2015.
• IRNSS-1E and 1F followed in January 2016 and March 2016.
• IRNSS-1G flew on PSLV-C33 on 28 April 2016.

What did the IRNSS-1H failure teach?

PSLV-C39 carried IRNSS-1H on 31 August 2017. The heat shield did not separate, so the satellite stayed trapped inside. Business Standard called it the first failure in 35 PSLV launches.

ISRO then launched IRNSS-1I on PSLV-C41 on 12 April 2018. ISRO calls it the eighth navigation satellite to join the series.

What does each satellite carry?

A navigation payload sends signals to users. A C-band ranging payload helps fix the satellite’s exact distance. A rubidium atomic clock keeps time. ISRO lists a ten-year mission life.

Two things hit the constellation in 2026. One satellite reached the end of its design life. A clock then failed.

What happened to IRNSS-1F?

IRNSS-1F finished its ten-year design life on 10 March 2026. On 13 March 2026 its procured on-board atomic clock stopped working. ISRO says it can still send one-way broadcast messages.

What do the PIB replies say?

• 25 March 2026: Eleven NavIC satellites had been launched and eight were functional. Three were broadcasting navigation signals. Five could send one-way messages.
• 29 July 2026: Three satellites give positioning, navigation and timing. They are IRNSS-1B, IRNSS-1I and NVS-01.
• The rule: Basic positioning needs at least four operational satellites.

What does that mean today?

PIB says NavIC cannot give a standalone positioning service now. Its timing service still works. The armed forces use several systems together, including NavIC.

ISRO planned five second-generation satellites, NVS-01 to NVS-05. They keep the base constellation going and add the L1 band.

What did NVS-01 do?

NVS-01 flew on GSLV-F12 on 29 May 2023. ISRO says an indigenous atomic clock flew for the first time on this satellite.

What went wrong with NVS-02?

• The launch: GSLV-F15 lifted off on 29 January 2025 at 06:23 hrs. It placed NVS-02 in the intended geosynchronous transfer orbit.
• The fault: The valves that admit oxidiser to the thrusters did not open. The satellite could not raise its orbit.
• The plan: NVS-02 was meant to sit at 111.75°E and replace IRNSS-1E. It weighs 2,250 kg.
• The cause: An ISRO committee found that a signal to a key valve never arrived. At least one connection in both the main and backup lines had failed.
• The fix: ISRO says the committee’s changes worked on CMS-03, launched on 2 November 2025.

PIB said on 29 July 2026 that NVS-03 is ready for launch. NVS-04 and NVS-05 are in an advanced stage.

PIB listed the uses on 10 December 2025. The Government has not made NavIC compulsory. Talks on that are going on.

What are the main pilot projects?

• Trains: More than 10,000 trains carry NavIC tracking devices.
• Fishing boats: More than 30,000 vessels have NavIC transponders.
• Vehicles: More than 140 device models are certified. They are fitted in more than 15 lakh vehicles.
• Time: Secondary timescales use NavIC time-transfer receivers to spread Indian Standard Time.
• Phones: More than 60 smartphones from various makers support NavIC.

How does NavIC help in disasters?

PIB says NavIC alerts run under the SACHET project of the National Disaster Management Authority. The NavIC signal can carry short text messages. They warn of floods, earthquakes, tsunamis, cyclones and landslides.

Are the chips made in India?

PIB reported in September 2023 that Manjeera Digital Systems of Hyderabad designed a baseband chip. Earlier NavIC phones used chips from Qualcomm of the USA and Mediatek of Taiwan.

These three names appear together in exams. Keep their jobs apart.

What is the difference in a table?

What is GAGAN?

GAGAN is India’s space-based augmentation system. PIB says it is operating and serves air navigation. Talks with the Airports Authority of India on NavIC for air traffic are still going on.

Does India use only NavIC?

No. PIB said on 29 July 2026 that the armed forces use many systems together, including NavIC. It says users face no vulnerability because most uses combine systems.

Big space projects often cost more than planned. NavIC is an example.

How did the cost change?

The Cabinet approved Rs 1,420 crore on 9 May 2006. The Planetary Society says the cost rose to Rs 3,260 crore, or USD 527.9 million, by 2014. It adds that the system was meant to be running by December 2015.

What is the roadmap?

• Complete the NavIC base layer constellation.
• Improve services to meet what users need.
• Build indigenous technology, including a space-grade atomic clock, for self-reliance.

That roadmap comes from the PIB reply of 25 March 2026.

What is the policy debate?

• The Government has not mandated NavIC. Talks continue.
• NavIC civilian signals are open to anyone inside the coverage area.
• International satellite navigation providers talk to ISRO about signal coordination.

UPSC asked about NavIC’s need and its use in the 2018 Mains. This card gives the wording, an outline and the traps.

What did the past paper ask?

How could you answer it?

• Need: Open with foreign dependence and the Kargil denial of GPS data.
• Design: Name the seven satellites and the 1,500 km service area.
• Use: Cover civilian and strategic services, trains, boats, vehicles, time and disaster alerts.
• Limit: Add the 2026 shortage of working satellites.

What are the traps?

1. Names. NavIC is the operating name. IRNSS is the older name.
2. Orbits. Three satellites are in GEO and four are in GSO. None are in medium Earth orbit.
3. Services. SPS is civilian. RS is strategic.
4. Bands. L5 and S came first. L1 is the new civilian band.
5. Eighth satellite. IRNSS-1H failed in 2017. IRNSS-1I flew in 2018.
6. Counts. Eight functional on 25 March 2026. Three giving positioning on 29 July 2026.
7. Timing figure. ISRO’s pages give both 50 ns and 40 ns.