Introduction

IRNSS (NavIC) satellite stands for Indian Regional Navigation Satellite System. It is India’s indigenous regional satellite navigation system, now popularly known as NavIC, which means Navigation with Indian Constellation. ISRO states that the system is designed to provide accurate Position, Velocity and Timing services over India and an area extending about 1,500 km beyond the Indian landmass.

IRNSS and NavIC

IRNSS is the original programme name, while NavIC is the operational and public name of the system. ISRO notes that the name NavIC was given after completion of the initial constellation in April 2016.

Nature of the system

NavIC is a regional navigation satellite system, not a global one like GPS, GLONASS, Galileo, or BeiDou. Its main purpose is to ensure that India has an independent navigation capability under its own control, especially for strategic and civilian uses in the Indian region. ISRO explicitly notes that NavIC is fully under the control of the Government of India and does not depend on foreign systems for regional position services.

Constellation and satellites

ISRO describes NavIC as being designed around a constellation of 7 satellites supported by a network of ground stations operating continuously. The designed configuration consists of:

• 3 satellites in geostationary orbit
• 4 satellites in inclined geosynchronous orbit

ISRO also states that it has built a total of nine satellites in the IRNSS series, of which eight are currently in orbit.

Orbital arrangement

The NavIC constellation is arranged in a way that improves coverage over India and the surrounding region.

ISRO gives the following designed orbital layout:

• geostationary satellites at 32.5°E, 83°E and 129.5°E
• inclined geosynchronous satellites with equatorial crossings at 55°E and 111.75°E, with 29° inclination

Services provided

NavIC provides two main services:

• Standard Positioning Service, which is available for civilian users
• Restricted Service, which is an encrypted service meant for authorized users

ISRO states that the Standard Positioning Service provides position accuracy of better than 20 metres and timing accuracy of better than 40 nanoseconds over the service area.

Frequencies and modernization

Traditionally, NavIC services were associated with L5 and S band. ISRO has also moved toward broader receiver compatibility by releasing signal specifications for L1 frequency, and newer satellites such as the NVS series are part of this modernization push.

NVS series

The NVS series represents the next generation of NavIC satellites. ISRO’s January 2025 note on NVS-02 described it as part of advancing India’s regional navigation capabilities. This shows that NavIC is no longer only an initial completed constellation but an evolving system being upgraded for continuity and better service.

Segments of the system

Like other satellite navigation systems, NavIC has three major segments:

• Space segment, consisting of the satellites
• Ground segment, consisting of control and monitoring stations
• User segment, consisting of receivers and end users who use the navigation signals

Importance

NavIC is important because it gives India an independent navigation capability for:

• terrestrial navigation
• marine navigation
• disaster management
• vehicle tracking
• timing applications
• strategic and defence-related uses

Its larger significance lies in technological self-reliance. During crises or strategic tensions, dependence on foreign navigation systems can become a vulnerability. NavIC reduces that risk for India within its service region. This follows directly from ISRO’s explanation of why India needs NavIC despite existing foreign systems.