Why is Indian Regional Navigational Satellite System (IRNSS) needed ? How does it help in navigation ?
Approach · directive: “why / how”
What it asks · Give the reasons India built its own regional navigation system and explain how its satellites and ground network deliver position and timing to users.
It asks 2 things — answer each
- Why: the strategic, service and self-reliance reasons India needs its own regional navigation system
- How: the constellation, signals and services through which IRNSS delivers position and timing
Open with · Satellite navigation underpins transport, telecom timing and defence; NavIC, erstwhile IRNSS, is ISRO's 7-satellite regional system with ground stations operating 24 x 7.
Cover
- Strategic autonomy: GPS and GLONASS belong to other governments and can be degraded or denied in a crisis.
- Critical services: disaster response, aviation, shipping and telecom timing need a signal India controls.
- Regional focus: covers India and up to 1,500 km beyond its boundary; builds indigenous satellites, ground segment and chipsets.
- Working: ground stations update orbit and clock data; satellites broadcast timed signals; receivers use four or more to fix position and time.
- Constellation and accuracy: three geostationary and four inclined geosynchronous satellites; better than 20 m in the primary service area.
- Services and uses: open SPS and encrypted Restricted Service; navigation, fishermen's alerts, disaster management; L1 signal from 2023 eases phone adoption.
Close with · A navigation system is only as useful as the receivers that read it; NavIC chipsets, used with global constellations, turn autonomy into everyday utility.
Add value (verified)
- NavIC, formerly IRNSS, has a constellation of 7 satellites and ground stations operating round the clock.ISRO: Satellite Navigation Services ↗“NavIC is designed with a constellation of 7 satellites and a network of ground stations operating 24 x 7.”
- IRNSS serves India and the region up to 1,500 km beyond its boundary, its primary service area.ISRO: IRNSS Programme ↗“It is designed to provide accurate position information service to users in India as well as the region extending up to 1500 km from its boundary, which is its primary service area.”
- IRNSS is designed for position accuracy better than 20 m in the primary service area.ISRO: IRNSS Programme ↗“The IRNSS System is expected to provide a position accuracy of better than 20 m in the primary service area.”
- IRNSS offers an open Standard Positioning Service and an encrypted Restricted Service.ISRO: IRNSS Programme ↗“IRNSS will provide two types of services, namely, Standard Positioning Service (SPS) which is provided to all the users and Restricted Service (RS), which is an encrypted service provided only to the”
- NavIC satellites from 2023 broadcast SPS signals in the L1, L5 and S bands; the L1 signal is interoperable with other GNSS.ISRO: Satellite Navigation Services ↗“All forthcoming (2023 onwards) NavIC satellites will broadcast SPS signals in L1, L5 and S bands.”
Question: UPSC's CS (Main) 2018, GS Paper I — paper ↗. Approach: Minimalist IAS, checked 16 Oct 2026 (how we verify) — UPSC publishes no model answers. ·
Model answer· 219words · Minimalist IAS
Satellite navigation underpins transport, telecom timing, banking and defence. NavIC, erstwhile IRNSS, is ISRO's regional system of 7 satellites and ground stations operating 24 x 7.
Why IRNSS is needed
- Strategic autonomy: GPS and GLONASS belong to other governments and can be degraded or denied in a crisis.
- Critical services: disaster response, aviation, shipping and telecom timing need a signal India controls.
- Regional focus: service over India and up to 1,500 km beyond its boundary, its primary service area.
- Self-reliance: indigenous satellites, ground network and chipsets.
How it helps in navigation
- Ground stations update orbit and clock data
- satellites broadcast time-stamped signals
- receiver measures delays from four or more
- position and time fixed
- Constellation: three geostationary and four inclined geosynchronous satellites stay high in India's sky.
- Accuracy: better than 20 m in the primary service area.
- Two services: an open Standard Positioning Service for all users and an encrypted Restricted Service for authorised users such as the armed forces.
- Uses: terrestrial, aerial and marine navigation, fishermen's alerts and disaster management.
- Wider reach (since then): satellites from 2023 add a civilian L1 signal, interoperable with GPS, Galileo and BeiDou, easing use in phones.
A navigation system is only as useful as its receivers; NavIC chipsets in phones and vehicles, used with global constellations, will turn strategic autonomy into everyday utility.
Prepared by Minimalist IAS to the answer standard of Shivam Singh (mentor, 7 years) · facts checked against official sources (how we verify) · updated 16 Oct 2026. UPSC publishes no model answers: compare your structure and coverage with this, then write your own.
