NAVIC: ISRO'S NEW SATELLITE NVS-03 TO RESTORE INDIA'S REGIONAL NAVIGATION SYSTEM

30 Oct 2026

Tags: Science & Technology   Emerging Tech   Space technology

Source: The Indian Express

Context: ISRO is scheduled to launch NVS-03, the third satellite of the second-generation navigation satellite series, to restore the functioning of India's satellite-based positioning system, NavIC.

• Background: NavIC has stopped providing positioning data because of the failure of atomic clocks, completion of satellite mission lives and unsuccessful replacement satellite launches.
• Strategic significance: A functional indigenous navigation system reduces India's dependence on foreign satellite navigation systems and strengthens strategic autonomy.

Navigation with Indian Constellation (NavIC)

• Official name: Navigation with Indian Constellation (NavIC), previously known as the Indian Regional Navigation Satellite System (IRNSS).
• Developed by: Indian Space Research Organisation (ISRO).
• Coverage: Designed as a seven-satellite regional navigation constellation covering the Indian subcontinent and an area extending approximately 1,500 km beyond India's boundaries.
• Positioning accuracy: Designed to provide:
  • Standard Positioning Service (SPS): Open to civilian users, with accuracy of approximately 10 metres.
  • Restricted Service (RS): Encrypted service intended for authorised users, including strategic and military applications.
• Advantage over GPS: NavIC provides stronger regional coverage over the Indian landmass, particularly in certain difficult terrains such as valleys and forests, where GPS signals may be received at unfavourable angles.
• Applications: Navigation, transportation, disaster management, maritime operations, military applications and location-based services.

Why Did NavIC Become Non-functional?

• Satellite failures: ISRO launched 11 navigation satellites since July 2013 for a mission costing approximately ₹2,250 crore, but six satellites failed, primarily due to atomic clock defects and orbital problems.
• Atomic clock failures: Several initial satellites carried imported atomic clocks that malfunctioned, affecting their ability to provide accurate positioning information.
• Delayed development of receivers: According to a 2018 CAG report, development of consumer-end receivers, required for devices such as mobile phones to access NavIC signals, began only in 2017. This resulted in underutilisation of the satellites' operational life.
• Failed replacement satellites:
  • IRNSS-1H: Failed to reach orbit after the heat-protective payload fairing of the PSLV failed to separate.
  • NVS-02: Successfully entered a highly elliptical transfer orbit, but its propulsion system failed to perform the manoeuvres required to reach its designated final orbit.
• Completion of satellite life: Most satellites in the original constellation had completed their designed 10-year mission life.
• Official confirmation: The Centre informed Parliament that the constellation was no longer providing positioning data.

Improvements in Second-Generation Navigation Satellites

• Indigenous atomic clocks: Second-generation satellites, beginning with NVS-01, carry indigenously developed atomic clocks, reducing dependence on imported components.
• Extended mission life: Their designed mission life has increased from 10 years to 12 years.
• Additional frequency band: They transmit signals through three frequency bands — L1, L5 and S, compared with the two bands (L5 and S) used by the earlier generation.
• Improved interoperability: The additional L1 frequency improves compatibility with other satellite navigation systems, particularly GPS.
• Wearable device compatibility: L1 signals facilitate integration with low-power, single-frequency chips used in smartwatches and other wearable devices.
• Reliability improvements: More comprehensive checks have been undertaken to prevent propulsion-system failures similar to those experienced by NVS-02.

Global Navigation Satellite Systems (GNSS)

There are four major global satellite navigation systems:

• GPS (United States): Global Positioning System.
• GLONASS (Russia): Global Navigation Satellite System.
• Galileo (European Union): European global satellite navigation system.
• BeiDou (China): Chinese global satellite navigation system.

India's position: NavIC is a regional navigation system, unlike the four global systems. India has developed an indigenous regional satellite navigation capability.

How Does a Satellite Navigation System Work?

• Atomic clocks: Navigation satellites carry highly precise atomic clocks to generate accurate time signals.
• Signal transmission: Satellites continuously transmit signals containing their position and the precise time of transmission.
• Distance calculation: Receivers calculate the distance from satellites by measuring the time taken by signals to reach them.
• Position determination: Signals from multiple satellites are used to determine the receiver's location through trilateration.
• Importance of accuracy: Even a small error in time measurement can result in significant errors in calculated location because satellite signals travel at the speed of light.

Conclusion: The NVS-03 mission is important for restoring India's regional satellite navigation capability, strengthening indigenous technological capacity and reducing dependence on foreign navigation systems. The success of NavIC will also depend on the reliability of its satellite constellation and wider adoption of compatible receivers in civilian and strategic applications.