Samstag, 16. Mai 2015 - 11:10 Uhr
The Indian Space Research Organisation (ISRO) is close to commissioning its new, home-made radar system that is capable of tracking several objects at the same time.
The radar will give ISRO the capability to better handle future space missions that involve re-entry of modules back into the earth’s atmosphere, and to track space debris.
The system will be tested during the next PSLV rocket launch in June; its commissioning could take three more months.
Disclosing the ‘multi object tracking radar’ to journalists here, M Y S Prasad, Director, Satish Dhawan Space Centre (from where Indian rockets are launched), said the radar could see objects as small as half a square meter in size, up to 1,000 km away.
“As far as we know, only five other companies in the world have the capability to build radars of this sophistication,” Prasad said, naming Raythaeon, Northrop Grummer, Lockheed Martin, of the US, Thales, Canada-Europe, Elta of Israel and NEC of Japan.
While it would cost Rs. 800 crore to buy a radar of comparable capabilities from the international market, ISRO built it for Rs. 245 crore, without any dedicated manpower, Prasad said.
V Seshagiri Rao, a former Director of the radar project, said the software developed in-house would be worth another Rs. 100 crore. The project was approved in August 2012 and has been completed in time.
Unlike the disc radars that keep spinning, the 35-tonne MOTR is a stationary, 12-metre-long, 8-metre-tall rectangular radar that contains 4,068 individual radiating elements. All these emit radio-frequency waves that combine to form a single beam. The beam can be electronically steered so that the a third of the sky is scanned. Since the radar’s base can be rotated to three positions, the entire sky can be covered.
Without this radar it would be extremely difficult for ISRO to handle manned space missions that involve the ‘crew module’ (and some other parts of the rocket) re-entering the atmosphere, because tracking them as they descend is crucial.
Since the radar can also track small objects, ISRO expects to use it to protect satellites in the ‘low earth orbit’ region (mainly, remote sensing satellites) from being hit by debris.
ISRO today uses NASA’s debris data for that purpose. Prasad said ISRO had to manoeuvre satellites out of harm’s way as many as 12 times in the last five years. Now the data from the radar will supplement NASA data to enhance ISRO’s capacity to protect satellites.
All but the dome that covers the whole system were designed by ISRO and made by Indian industry, Prasad said. The dome had to be imported because there was no Indian supplier who could assure ‘RF transparency’.
He said the radar could be put to several other uses as well. For instance, less sophisticated versions could be used by airports.
He did not want to comment on the military uses of the radar, but he observed that similar radars of Israeli make are being bought by military establishments all over the world.
Quelle: The Hindu