Isro closer to setting up own navigation system with IRNSS-1F launch

Indian Space Research Organisation (Isro) today launched its sixth navigation satellite IRNSS-1F, taking India closer towards joining a select group of countries that have their own satellite navigation system.

The satellite was launched on board Isro's trusted workhorse, the Polar Satellite Launch Vehicle (PSLV C32), as scheduled at 16:00 hours, after the green signal was given by Mission Readiness Review Committee and Launch Authorisation Board.

The PSLV rocket, standing 44.4 metres tall and weighing 320 tonne, lifted off from the Sriharikota space port carrying the 1,425 kg IRNSS-1F satellite as scheduled.

In around 20 minutes into the flight, the PSLV rocket ejected its sole passenger, IRNSS-1F, at an altitude of 488.9 km.

The satellite's control was then taken over by the Mission Control Facility (MCF) at Hassan in Karnataka. It will manage the satellite's orbit raising operations firing the on-board motors till it is placed in its slotted orbit.

Designed for a life cycle of 12 years, the satellite has two payloads - one for navigation and the other for ranging.

IRNSS-1F will transmit navigation service signals to the users with its payload operating in the L5-band and S-band. A highly accurate rubidium atomic clock is part of the navigation payload of the satellite.

IRNSS-1F payload also consists of a C-band transponder (automatic receivers and transmitters of radio signals), which facilitates accurate determination of the range of the satellite.

Isro will be completing the seven-satellite navigation system with the launch of yet another satellite this year.

Isro is expected to launch its seventh navigation satellite, IRNSS-1G, somewhere in the second half of 2016.

When fully integrated, the IRNSS will provide two types of services - standard positioning service and restricted service. The former is provided to all users and the latter is an encrypted service for authorised users.

India will not then need to rely on navigational services like the US-based Global Positioning System as the IRNSS will be providing better navigation services compared with others.

Five satellites of the IRNSS system - IRNSS-1A, launched on 1 July 2013; IRNSS-1B, launched on 4 April 2014; IRNSS-1C launched on 16 October 2014; IRNSS-1D launched on 28 March 2015; and IRNSS-1E that was launched on 20 January 2016 – are already in operation and the launch of the seventh satellite will complete the system.