India's Own GPS- IRNSS

                         Indian Regional Navigation Satellite System

IRNSS- Indian Regional Navigation Satellite System is an autonomous regional satellite navigation system being developed by ISRO which would be completely under Government of India.

The satellite is designed to provide accurate position information service to users in India as well as the region extending up to 1,500 kms from its boundary.

Application of IRNSS includes terrestrial, aerial and marine navigation, disaster management, vehicle tracking and fleet management, integration with mobile phones, precise timing, mapping and geodetic data capture, terrestrial navigation aid for hikers and travellers, visual and navigation for drivers, said ISRO sources.

IRNSS will provide two types of services, including Standard Positioning Service (SPS), which is provided to all the users and Restricted Service (RS), which is an encrypted service provided only to the authorised users. The system is expected to provide a position accuracy of better than 20 m in the primary service area.

The satellite system also comprises of a space segment and a ground segment. The space segment consists of seven satellites, with three satellites in the geostationary orbit and four in an inclined geosynchronous orbit.

The IRNSS ground segment is responsible for navigation parameter generation and transmission, satellite controls, ranging and integrity monitoring and time keeping.

Why IRNSS?

To ease India’s dependence on America’s GPS and even to some extent on Russia’s Glonass, the Indian Space Research Organisation (ISRO) has built its own geo-spatial positioning system. The US doesn’t share military grade signals with countries but civilian signals are free to all. In times of war, and sometimes even otherwise, the signals can be corrupted and it can pose security problem.

Amid such uncertainties, when the default control and navigation systems in defence projects are equipped with GPS devices, a country’s security rides on these radio signals whose control lies elsewhere. For this reason, in its upgraded BrahMos missile, India has added Glonass receivers to the standard GPS receivers because Russia, unlike US, gives access to military signals. But India’s IRNSS is a regional system, not meant for offensive but defensive purposes.

Master Clock

But the heart of IRNSS lies in the master clock. “The Americans, the Europeans… all have their standard time. India also had to establish her own standard time. A master clock provides the timing reference for the generation of the navigation signal. This atomic clock maintains accuracy of better than 20 nano-seconds with respect to any universal time. It provides stability of 0.4 or 0.5 nanoseconds variation in a day.


India should also attract other countries in the region to use IRNSS. GPS is a success because the whole world uses it; even China is making its system, Compass, commercially available. At some point India needs to use its space faring abilities as soft power.