Monday, April 16, 2007

INSAT-4B Operational

From Jaisakthivel in Chennai, India via the Cumbre DX newsgroup. Source:

A month after Insat-4B was lofted into space from French Guiana, the Indian Space Research Organisation's latest communication satellite has become fully operational.

The spacecraft reached its final location of 93.5 deg E longitude on Thursday.

Within one month (of the launch), we have made it fully operational," Isro chairman G Madhavan Nair told reporters in Bangalore on Wednesday.

Insat-4B was successfully launched by Ariane-5 ECA on 12 March from Kourou, French Guiana. Following its launch, a series of orbit-raising operations were conducted to place the satellite in its near-geosynchronous orbit. After those operations were
completed, the deployment of its two solar panels and two antennas was carried out.

Insat-4B carries the following payloads:

12 Ku- band 36 MHz and 27 MHz usable bandwidth Transponders (9 and 3 numbers respectively) employing 140 W TWTAs to provide an EIRP of 52 dBW over the footprint covering Indian main land.

2 C-band 36 MHz bandwidth transponders employing 63 W TWTA to provide an EIRP 39 dBW with expanded coverage encompassing Indian geographical boundary, area beyond India in southeast and northwest regions.

Kalanithi Maran's Sun Group has booked seven Ku-band transponders on Insat-4B for its soon-to-launch DTH service Sun Direct, while Prasar Bharati's free-to-air (FTA) package DD Direct Plus has booked five.

Sun will be using MPEG-4 technology that will allow it to compress more TV channels per transponder. While MPEG-2 can pack in around 12 channels, the advanced compression technology will be able to accommodate over 20 channels.

Sun may consider itself lucky that the launch of Insat-4C satellite failed in July 2006 after the rocket carrying it veered off course and exploded. Sun had booked six Ku-band transponders (and one more for digital satellite news gathering) on it for its DTH service.

By being located on the same satellite, Sun's subscribers will be able to access DD Direct's channels without it having to separately put them on its transponders.