Indian Space Research Organization (ISRO) on 28 April 2016 launched India’s seventh navigation satellite of the Indian Regional Navigation Satellite System (IRNSS 1G) into a Sub-Geosynchronous Transfer Orbit (Sub-GTO) on-board PSLV-C33.



The satellite was launched from the First Launch Pad (FLP) of the Satish Dhawan Space Centre, Sriharikota, which is situated 90 kms from Chennai.

With this launch, India successfully joined the elite group of countries that have their own navigation system technology to cater to the mammoth navigational needs.

As in the previous six launches of IRNSS satellites, PSLV-C33 used ‘XL’ version of PSLV equipped with six strap-ons, each carrying 12 tons of propellant.

IRNSS-1G



IRNSS-1G is the seventh navigation satellite of the seven satellites constituting the IRNSS space segment. Its predecessors, IRNSS-1A, 1B, 1C, 1D, 1E and 1F were launched by PSLV-C22, PSLV-C24, PSLV-C26, PSLV-C27, PSLV-C31 and PSLV-C32 in July 2013, April 2014, October 2014, March 2015, January 2016 and March 2016 respectively.

Like all other IRNSS satellites, IRNSS-1G also has a lift-off mass of 1425 kg. The configuration of IRNSS-1G too is the same as IRNSS-1A, 1B, 1C, 1D, 1E and 1F.


Payloads

The satellite with a design life span of 12 years has two payloads for navigation and ranging.

• Navigation payload – It will transmit navigation service signals to the users. This payload will be operating in L5-band and S-band. A highly accurate Rubidium atomic clock is part of the navigation payload of the satellite.

• Ranging payload – It consists of a C-band transponder which facilitates accurate determination of the range of the satellite.

Features of IRNSS

• It consists of seven satellites to provide real-time data on the position of objects to aid road, air and maritime traffic apart from providing mapping and tracking services.

• It is an independent regional navigation satellite system designed to provide position information in the Indian region and 1500 km around the Indian mainland.

• It would provide two types of services, namely, Standard Positioning Services (SPS), which will be provided to all users, and Restricted Services (RS) that will be provided to authorised users only.

• Out of the seven satellites of the system, three are geostationary and four are non-geostationary.

• By using the IRNSS as a platform, the Government of India is planning to launch its own Global Navigational Satellite Services, GINS (Global Indian Navigation Satellite) system. It is similar to the Global Positioning System (GPS) of the USA.

While many countries in the world have more than 20 satellites in serving the navigational purpose Indian scientists can boast of by achieving the goal by launching the seventh satellite which in a way completes the constellation which was earlier planned.

This constellation will help ISRO to take help from the civilian needs to security or defence needs.