INSAT-4E

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INSAT 4E
GSAT-6 seen with two halves of payload faring of GSLV-D6.jpg
GSAT-6 seen with two halves of payload faring of GSLV-D6
Mission type Communication
Operator INSAT
COSPAR ID 2015-041A OOjs UI icon edit-ltr-progressive.svg
SATCAT no. 40880 OOjs UI icon edit-ltr-progressive.svg
Website https://www.isro.gov.in/Spacecraft/gsat-6
Mission durationPlanned: 9 years
Elapsed: 8 years, 6 months, 11 days
Spacecraft properties
Bus I-2K
Manufacturer ISRO Satellite Centre
Space Applications Centre
Launch mass2,117 kilograms (4,667 lb)
Dry mass985 kg (2,172 lb)
Power3.1 kilowatts
Start of mission
Launch date27 August 2015, 11:22 (2015-08-27UTC11:22Z) UTC
Rocket GSLV Mk.II D6
Launch site Satish Dhawan SLP
Contractor ISRO
Orbital parameters
Reference system Geocentric
Regime Geostationary
Longitude83°E
Epoch Planned
Transponders
Band5, C x S transponders (9 megahertz bandwidth)
5, S x C transponders (2.7 megahertz bandwidth)
  GSAT-16
GSAT-15  
 

INSAT-4E, also known as GSAT-6, is a member of the INSAT family and is a multimedia communication satellite that will offer a Satellite Digital Multimedia Broadcasting (S-DMB) service across several digital multimedia terminals or consoles which can be used to provide information services to vehicles on the fly and to the mobile phones. The satellite can be used for other social and strategic applications. [1] [2]

Contents

Satellite

Render of GSAT-6 spacecraft in deployed configuration Render of GSAT-6 spacecraft in deployed configuration.png
Render of GSAT-6 spacecraft in deployed configuration

INSAT-4E has five C x S transponders each of 9 MHz bandwidth and five S x C transponders each of 2.7 MHz bandwidth which will together cover the entire country. [3] GSAT-6 uses a 0.8 meter (fixed) and one 6 meter S-Band unfurlable antenna (transmit and receive). [4]

The unfurlable antenna weighing 18 kg has CFRP truss construction with aluminium alloy joints and its parabolic gold plated molybdenum mesh is supported and shaped by cable mesh structures. [5]

The cost of GSAT-6 satellite is ₹232 crore [6] and it is identical in configuration to GSAT-6A which was launched later.

Launch

ISRO successfully launched INSAT-4E on 27 August 2015, using a GSLV D6 Mk.II rocket flying from the Satish Dhawan Space Centre and inserted into a Geostationary Transfer Orbit (GTO) with injection parameters of 170 km x 35945 km, 19.96 degree inclination. [7] The cost of launch vehicle was around ₹276 crore. [6]

Orbit raising

Maneuvers to move the satellite into its designated geosynchronous orbit at 83 degrees East longitude were initiated on 28 August 2015 by firing motors on board the GSAT-6 satellite.

The GSAT-6 satellite's Liquid Apogee Motor (LAM) was fired for 3385 seconds at 08:35 hours IST on August 28 during the first orbit raising operation and modified the satellite orbit to 8,408 km (perigee height) by 35,708 km (apogee height) with an inclination of 7.5 degree and an orbital period of 13 hours, 15 minutes and 24 seconds. [8] [9]

Second orbit raising operation of GSAT-6 was successfully completed by firing the Apogee Motor for 2663 seconds at 11:10:53 hours IST on Aug 29, 2015. Realized orbit was 26,998 km (perigee height) by 35,682 km (apogee height) with an inclination of 0.115 degree and an orbital period of 20 hours and 15 minutes. [10]

Third orbit raising operation of GSAT-6 was successfully completed by firing the Apogee Motor for 580.32 seconds at 07:46 hours IST on Aug 30, 2015. Deployment of the unfurlable antenna (UFA) also successfully completed with this. [11] The satellite was at 78 degrees east longitude and was drifting towards its final slot at 83 degrees east.

GSAT-6 was successfully positioned in its orbital slot of 83 degree east and collocated with INSAT-4A, GSAT-12, GSAT-10 and IRNSS-1C on September 6, 2015, morning, after carrying out four drift arresting maneuvers. [12]

Under-utilization of GSAT-6

According to Comptroller and Auditor General of India report submitted to parliament in 20 December 2022, the GSAT-6 satellite has remained largely underutilized since its launch in August 2015 which is almost half of the expected operational life of 12 years. The audit observed the lack of coordination between Department of Space and DRDO and the delay in establishing ground segment by DRDO as the reason behind this disuse. According to Department of Space the 20 per cent of the GSAT-6 capacity was used for its research projects and societal applications but was not aware of the status of utilization of the remaining capacity. [6]

See also

Related Research Articles

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The Indian National Satellite System or INSAT, is a series of multipurpose geostationary satellites launched by ISRO to satisfy telecommunications, broadcasting, meteorology, and search and rescue operations. Commissioned in 1983, INSAT is the largest domestic communication system in the Indo-Pacific Region. It is a joint venture of the Department of Space, Department of Telecommunications, India Meteorological Department, All India Radio and Doordarshan. The overall coordination and management of INSAT system rests with the Secretary-level INSAT Coordination Committee.

<span class="mw-page-title-main">Geosynchronous Satellite Launch Vehicle</span> Class of Indian medium-lift expendable launch vehicles, developed by ISRO

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<span class="mw-page-title-main">GSAT</span>

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GSAT-1 was an experimental communications satellite launched aboard the maiden flight of the GSLV rocket. The spacecraft was equipped with instrumentation to test Pulse-code modulation (PCM) transmitting on S-band frequencies and transponders operating in the C-band. The spacecraft was unable to complete its mission after a launch failure left it in a lower than planned orbit and propulsion issues prevented the satellite from correcting this via its own maneuvering system.

<span class="mw-page-title-main">GSAT-2</span>

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<span class="mw-page-title-main">Master Control Facility</span> Space research facility in Hassan, India

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<span class="mw-page-title-main">INSAT-3A</span> Multipurpose satellite launched in 2003

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References

  1. "ISRO proposes INSAT-4E satellite". spacedaily.com. Retrieved 2012-05-29.
  2. "Space Application center". sac.gov.in. Archived from the original on 3 March 2016. Retrieved 2012-05-29.
  3. "ISRO Proposes INSAT 4E Multimedia Mobile SBand Satellite Mission". spacedaily.com. 2 December 2005. Retrieved 5 March 2023.
  4. "GSAT-6 - ISRO". www.isro.gov.in. 27 August 2015. Retrieved 5 March 2023.
  5. "Upagrah newsletter Apr-June 2018" (PDF). Archived from the original (PDF) on 9 November 2018.
  6. 1 2 3 "Report of the Comptroller and Auditor General of India for the year ended March 2021" (PDF). 19 December 2022. Archived from the original (PDF) on 20 December 2022.
  7. "ISRO's GSLV D-6 puts GSAT-6 satellite in orbit". The Hindu. 27 August 2015.
  8. "First orbit raising operation of GSAT-6 completes successfully". Press Trust of India. PTI. 29 August 2015.
  9. "GSAT-6 Update: First orbit raising operation of GSAT-6 was successfully completed". isro.org. Archived from the original on 31 August 2015. Retrieved 30 August 2015.
  10. "Second orbit raising operation of GSAT-6 was successfully completed". isro.org. Archived from the original on 31 August 2015. Retrieved 30 August 2015.
  11. "Third orbit raising operation of GSAT-6 was successfully completed". isro.org. Archived from the original on 1 September 2015. Retrieved 30 August 2015.
  12. "GSAT-6 has been successfully positioned in its orbital slot". isro.org. Archived from the original on 2015-09-10. Retrieved 2015-09-07.