Mudasir 4K
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ISRO has given the nation a much needed Divali gift
- the indigenously built GSAT-15 DTH Satellite.
LAUNCH
GSAT-15 was successfully launched by the European Ariane 5 VA-227 launch vehicle at 3:04 AM on November 11, 2015, from Kourou in French
Guyana in South America.
After a smooth 11 hours, 30-minute countdown, the
GSAT-15 was lofted for 43 minutes and 24 seconds. It separated from the Ariane 5 upper stage in an elliptical Geosynchronous Transfer Orbit (GTO) with a perigee (nearest point to Earth) of 250 km
and an apogee (farthest point to Earth) of 35,819 km, inclined at an angle of 3.9 degree to the
equator.
ISRO's Master Control Facility (MCF) at Hassan in Karnataka took over the command and control of GSAT-15 immediately after its separation from the
launch vehicle. During the next few days, orbit raising manoeuvres were performed to place the satellite in the
Geostationary Orbit (36,000 km above the equator) by using the satellite's propulsion system in steps. After the completion of orbit raising operations, the
2 solar arrays and both antenna reflectors were deployed.
ISRO paid Arianespace Rs. 581 Crores for the launch, and as lofted into orbit along with the
Arabsat-6B (BADR-7) satellite.
CO-LOCATED AT 93.5 DEG
GSAT-15 will be co-located at 93.5 degrees East longitude, along with the operational INSAT-3A and INSAT-4B satellites.
GSAT-15 has a projected life of 12 years. The GSAT-15 will augment the capacity of the INSAT-3A and INSAT-4B. The INSAT-3A has been operational, normally, for last 12 years. However, half of the INSAT-4B is
dead since 2010 when one of its solar panels developed a fault.
PAYLOADS
The tenth GSAT satellite, GSAT-15 is similar to the
GSAT-10 satellite. Weighing 3,164 kilograms it has 24 Ku Band (DTH) transponders, and has cost the nation Rs. 278 crores. GSAT-15 also has a GPS Aided GEO Augmented
Navigation (GAGAN) payload operating in L1 and L5
bands. it is the third satellite to carry Gagan payload after GAST-8 and GSAT-10, which are
already providing Indian GPS services from orbit. GSAT-15, also carries 2 Ku-band beacons to help accurately point ground antennas to the satellite.
FREEDISH TO SHIFT
Doordarshan's Free Dish DTH service will soon migrate to GSAT-15, since the INSAT-4B satellite is already half non-functional. Launched in March
2007, INSAT 4B was reduced to half its functions in 2010 after one of its power-generating solar panels developed a snag.
FreeDish will probably be allocated 6 transponders
on the new GSAT-15. FreeDish currently offers MPEG- 2 compressed 64 Standard Definition TV channels along with 24 radio channels. it plans to increase its channel count to 100 TV channels, with
additional channels downlinked using the more bandwidth efficient MPEG-4 compression.
FreeDish currently auctions its MPEG-2 slots @ a base price of Rs. 4.3 Crores per year.
Doordarshan DDG (Comm. & Sales/ IR & IMD/ DCD)
CK Jain told the press that a specific transition date has not yet been finalised. Since the FREE Dish downlink frequencies will change with the transition,
the FreeDish STBs will all have to be re-tuned.
ACUTE KU BAND SHORTAGE
India currently has an acute shortage of transponders in space. Even by ISRO's own plan, India should have had 500
transponders by end of 2012 (11th plan, 2007-12) and 800 transponders by 2017 (12th plan, 2012-17) . However, today ISRO has only 200 operational
transponders. The 2014 Comptroller and Auditor
General report has criticised ISRO's performance in this arena. India currently rents more than 100 transponders
from foreign countries / companies.
COMMERCIAL IMPLICATIONS
The 24 Ku Band transponders on the GSAT-15 will more than double India's DTH capacity.
Indian DTH currently uses 76 Ku band transponders of which only 19 are on ISRO satellites.
Sun Direct & FreeDish DTH are likely to benefit the most from the launch of the new satellite, since they currently use transponders at 93.5 degrees East.
SUN DIRECT
Sun Direct had all its channels beamed from 5 transponders on the INSAT-4B. But its July 2010,
power failure forced the shutdown of 4 transponders, compelling Sun TV to move most of its channels to the neighbouring Measat-3. Like Dish TV, Sun Direct uses 2 satellites to ensure that it has enough capacity. For beaming standard- definition channels, it uses the Measat- 3, located at
91.5 degrees east.
Sun Direct DTH uses one transponder on INSAT- 4B
located at 93.5 degrees east to beam its HD channels. As a result, any customer who subscribes to HD packages gets a bigger dish antenna which
is capable of receiving signals from both satellites. The GSAT-15 will enable Sun Direct to increase its HD channels, which are the lowest of any Indian DTH operator, with the exception of Reliance Digital
TV. A single 36 MHz transponder can beam 8 HD
channels.
HD ON DTH
Dish TV holds the distinction of having the highest number of HD channels in India. Using its 6
transponders on Asiasat-5, the DTH player offers close to 50 HD channels, while Videocon D2h and Airtel Digital TV, which are also aggressive on the HD channel front, offer about 30 channels each.
TATASKY
Tata Sky has worked around its meagre transponder capacity by migrating from MPEG-2 to MPEG-4 compression. Unfortunately for Tata Sky, the
GSAT-15 is too far away from its GSAT-10 satellite @ 83 degrees East. However, there is hope that the government could move some of its existing traffic
from GSAT-10 to GSAT-15. This would help ISRO'S fulfil its deal to provide extra capacity to Tata Sky on GSAT-10, which was launched in 2012.
GSAT-17 & 18
India has also booked 2 more Ariane launches for the GSAT-17 (2016) & GSAT-18 (2017)
communications satellites. ISRO hopes that beyond 2018, its indigenously developed GSLV will loft all future ISRO satellites into geo orbit.
www.scatmag.com/article6.htm
- the indigenously built GSAT-15 DTH Satellite.
LAUNCH
GSAT-15 was successfully launched by the European Ariane 5 VA-227 launch vehicle at 3:04 AM on November 11, 2015, from Kourou in French
Guyana in South America.
After a smooth 11 hours, 30-minute countdown, the
GSAT-15 was lofted for 43 minutes and 24 seconds. It separated from the Ariane 5 upper stage in an elliptical Geosynchronous Transfer Orbit (GTO) with a perigee (nearest point to Earth) of 250 km
and an apogee (farthest point to Earth) of 35,819 km, inclined at an angle of 3.9 degree to the
equator.
ISRO's Master Control Facility (MCF) at Hassan in Karnataka took over the command and control of GSAT-15 immediately after its separation from the
launch vehicle. During the next few days, orbit raising manoeuvres were performed to place the satellite in the
Geostationary Orbit (36,000 km above the equator) by using the satellite's propulsion system in steps. After the completion of orbit raising operations, the
2 solar arrays and both antenna reflectors were deployed.
ISRO paid Arianespace Rs. 581 Crores for the launch, and as lofted into orbit along with the
Arabsat-6B (BADR-7) satellite.
CO-LOCATED AT 93.5 DEG
GSAT-15 will be co-located at 93.5 degrees East longitude, along with the operational INSAT-3A and INSAT-4B satellites.
GSAT-15 has a projected life of 12 years. The GSAT-15 will augment the capacity of the INSAT-3A and INSAT-4B. The INSAT-3A has been operational, normally, for last 12 years. However, half of the INSAT-4B is
dead since 2010 when one of its solar panels developed a fault.
PAYLOADS
The tenth GSAT satellite, GSAT-15 is similar to the
GSAT-10 satellite. Weighing 3,164 kilograms it has 24 Ku Band (DTH) transponders, and has cost the nation Rs. 278 crores. GSAT-15 also has a GPS Aided GEO Augmented
Navigation (GAGAN) payload operating in L1 and L5
bands. it is the third satellite to carry Gagan payload after GAST-8 and GSAT-10, which are
already providing Indian GPS services from orbit. GSAT-15, also carries 2 Ku-band beacons to help accurately point ground antennas to the satellite.
FREEDISH TO SHIFT
Doordarshan's Free Dish DTH service will soon migrate to GSAT-15, since the INSAT-4B satellite is already half non-functional. Launched in March
2007, INSAT 4B was reduced to half its functions in 2010 after one of its power-generating solar panels developed a snag.
FreeDish will probably be allocated 6 transponders
on the new GSAT-15. FreeDish currently offers MPEG- 2 compressed 64 Standard Definition TV channels along with 24 radio channels. it plans to increase its channel count to 100 TV channels, with
additional channels downlinked using the more bandwidth efficient MPEG-4 compression.
FreeDish currently auctions its MPEG-2 slots @ a base price of Rs. 4.3 Crores per year.
Doordarshan DDG (Comm. & Sales/ IR & IMD/ DCD)
CK Jain told the press that a specific transition date has not yet been finalised. Since the FREE Dish downlink frequencies will change with the transition,
the FreeDish STBs will all have to be re-tuned.
ACUTE KU BAND SHORTAGE
India currently has an acute shortage of transponders in space. Even by ISRO's own plan, India should have had 500
transponders by end of 2012 (11th plan, 2007-12) and 800 transponders by 2017 (12th plan, 2012-17) . However, today ISRO has only 200 operational
transponders. The 2014 Comptroller and Auditor
General report has criticised ISRO's performance in this arena. India currently rents more than 100 transponders
from foreign countries / companies.
COMMERCIAL IMPLICATIONS
The 24 Ku Band transponders on the GSAT-15 will more than double India's DTH capacity.
Indian DTH currently uses 76 Ku band transponders of which only 19 are on ISRO satellites.
Sun Direct & FreeDish DTH are likely to benefit the most from the launch of the new satellite, since they currently use transponders at 93.5 degrees East.
SUN DIRECT
Sun Direct had all its channels beamed from 5 transponders on the INSAT-4B. But its July 2010,
power failure forced the shutdown of 4 transponders, compelling Sun TV to move most of its channels to the neighbouring Measat-3. Like Dish TV, Sun Direct uses 2 satellites to ensure that it has enough capacity. For beaming standard- definition channels, it uses the Measat- 3, located at
91.5 degrees east.
Sun Direct DTH uses one transponder on INSAT- 4B
located at 93.5 degrees east to beam its HD channels. As a result, any customer who subscribes to HD packages gets a bigger dish antenna which
is capable of receiving signals from both satellites. The GSAT-15 will enable Sun Direct to increase its HD channels, which are the lowest of any Indian DTH operator, with the exception of Reliance Digital
TV. A single 36 MHz transponder can beam 8 HD
channels.
HD ON DTH
Dish TV holds the distinction of having the highest number of HD channels in India. Using its 6
transponders on Asiasat-5, the DTH player offers close to 50 HD channels, while Videocon D2h and Airtel Digital TV, which are also aggressive on the HD channel front, offer about 30 channels each.
TATASKY
Tata Sky has worked around its meagre transponder capacity by migrating from MPEG-2 to MPEG-4 compression. Unfortunately for Tata Sky, the
GSAT-15 is too far away from its GSAT-10 satellite @ 83 degrees East. However, there is hope that the government could move some of its existing traffic
from GSAT-10 to GSAT-15. This would help ISRO'S fulfil its deal to provide extra capacity to Tata Sky on GSAT-10, which was launched in 2012.
GSAT-17 & 18
India has also booked 2 more Ariane launches for the GSAT-17 (2016) & GSAT-18 (2017)
communications satellites. ISRO hopes that beyond 2018, its indigenously developed GSLV will loft all future ISRO satellites into geo orbit.
www.scatmag.com/article6.htm
