Countdown to launch India's own GPS begins

Like the US' GPS (Global Positioning System) that gives the exact location of moving aircraft, ships, vehicles and even people carrying smart phones, India will soon have its own satellite-based navigation system.

Like the US' GPS (Global Positioning System) that gives the exact location of moving aircraft, ships, vehicles and even people carrying smart phones, India will soon have its own satellite-based navigation system. India’s equivalent of the GPS will be called the Indian Regional Navigational Satellite System or IRNSS, a cluster of seven satellites being developed by the Indian Space Research Organisation (ISRO) – IRNSS-1A, IRNSS-1B, IRNSS-1C, IRNSS-1D, IRNSS-1E, IRNSS-1F and IRNSS-1G. The first satellite – IRNSS-1A which will weigh 1,425 kg – is expected to be launched on July 1, 2013. Launched from Sriharikota on PSLV-C22 rockets, all the seven satellites are expected to be in orbit by early 2015 and will operate in allweather conditions. Three satellites will be placed in the geo-stationary orbit and the rest in geosynchronous orbits. The satellites will continuously calculate and relay position information to aircraft in the Indian air space, ships sailing in the Indian Ocean, motorists all over the country and mobile handsets, among others. The satellites will provide position accuracy to within 10m to 20m. The system is intended to provide an absolute position accuracy of better than 10m throughout the Indian landmass and better than 20m in the Indian Ocean. So if you are travelling on the road and want to locate an address, a receiver in your car tuned into IRNSS will tell you the exact position of the address to within 10m of the building. It will give both visual and voice navigation instructions. But is there a need for IRNSS when there already exists a reliable satellite navigation system in the form of the GPS? And will it be as reliable as the GPS? Officials say the Indian system will be more accurate in this part of the globe. The satellite navigation system will cover the Indian subcontinent and around 1,500 km beyond the country’s geographical boundaries. Besides the satellites or the space segment, the system will also have a ground segment, comprising spacecraft control facility, range and integrity monitoring stations, navigation centre, network timing facility, ranging stations and data communication network, and an user segment – aircraft, ships, motorists et al. The ground segment would be responsible for maintenance and operation of the satellite constellation. “It will be our own system. It will make us independent in the area of navigation. At the moment we depend on US’ GPS or Russia’s GLONASS system. They can block signals anytime if they want,” an ISRO official said. “All satellites will be placed in such a way that these will keep looking at India all the time,” he said. As part of the ground segment, a navigation centre has been unveiled in Bangalore rural district at the Indian Deep Space Network complex at Byalalu. The centre will be responsible for time reference, generation of navigation messages and monitoring and control of ground facilities.