New Delhi, Dec. 22: India today launched its heaviest satellite till date that will allow television viewers across the country to directly receive 150 channels, clearer and sharper than ever before, via antenna no larger than dinner plates.
Insat-4A, India’s first satellite devoted to direct-to-home (DTH) transmission, took off at 4.03 am IST aboard the European launch vehicle Ariane-5G, from Kourou, French Guiana. The spaceship, weighing 3,080 kg at take-off, was accompanied by a European meteorological satellite, MSG-2.
The Indian Space Research Organisation’s master control facility (MCF) at Hassan in Karnataka took control of Insat-4A at 4.32 am after Ariane-5G had placed it in a temporary elliptical orbit. The satellite’s progress thus far, according to scientists at Isro, is satisfactory. In the following few days, the MCF will conduct manoeuvres on the satellite to take it to a final height of 36,000 kilometres above the earth.
The scientists behind Insat-4A say the transponders ? data transfer devices aboard satellites ? on it are the most powerful ever on an Indian satellite.
More important, they say, these are more powerful than the ones being currently used for DTH transfer by public broadcaster Doordarshan, and will result in significantly better-quality television viewing.
“The transponders on this satellite have almost a lakh times the power of transponders currently used for DTH transmission by DD. There is no comparison,” said Krishnamurthy of Isro.
“Higher power directly results in the desired signal being stronger than any surrounding unwanted electrical signal. Therefore, we have clearer transmission, or in other words, better viewing.”
The greater power of the signals, the scientists say, will enable dishes of less than 18-inch diameter to catch a frequency band they call the “Ku-band”, needed for DTH transfer. Dishes of around twice the size were required till now.
The launch of the satellite also represents a giant leap by India towards self-sufficiency in DTH technology, the scientists added.
Doordarshan has been using Dutch-owned New Skies Satellites (NSS) for DTH transfer since December 2004, when the government first introduced these services in India. Indian satellites, till now, have focused on telecommunications, broadcasting and meteorology.
“Doordarshan and other private broadcasters will no longer need to look beyond Insat satellites,” said Krishnamurthy.
While 12 transponders on Insat-4A are completely DTH-committed, there are 12 others which can be used either for DTH conveyance or for broadcasting and telecommunications.
The country’s latest space vehicle has a life of 12 years, is 2.8 metres in length, 2 metres wide and 1.77 meters high. Large solar panels are charging the three batteries that drive the satellite. The geostationary ship will be positioned at 83 degrees east longitude, at an inclination of 4.02 degrees with respect to the equator.
Insat-4A is the first of seven spaceships planned as part of the Insat-4 series. Insat-4B, too, will focus on DTH transfer.
