# GSAT

The GSAT (Geosynchronous Satellite) satellites are India's indigenously developed communications satellites, used for digital audio, data and video broadcasting. As of 5 December 2018, 20 GSAT satellites manufactured by ISRO have been launched, out of which 14 are in service.

## History

The GSAT series of geosynchronous satellites is a system developed by ISRO with an objective to make India self-reliant in broadcasting services. The system includes a total of 168 transponders (out of which 95 are leased out to provide services to broadcasters) in the C, Extended C and K$_u$ bands, providing services to telecommunications, television broadcasting, weather forecasting, disaster warning and search and rescue operations.

## List of GSAT satellites

This is a list of GSAT satellites and their status.
List of GSAT satellites :
| Satellite | Satellite | Satellite | Longitude | Date of launch | Launch vehicle | Lift-off mass | Status | Notes |
| GSAT series | INSAT series | Known as | Longitude | Date of launch | Launch vehicle | Lift-off mass | Status | Notes |
| GSAT-1 | - | GramSat 1 | 73° West (2000) 99° West (2000–2006) 76.85° West (2006–2009) | 18 April 2001 | GSLV Mk I D1 | 1,540 kg (3,400 lb) | Failed to orbit (Experimental satellite) | Envisaged as a technology demonstrator; Failed to achieve its target orbit, which prevented it from fulfilling its primary communications mission. |
| GSAT-2 | - | GramSat 2 | 47.95° East | 8 May 2003 | GSLV Mk I D2 | 1,825 kg (4,023 lb) | Decommissioned (Experimental satellite) | Experimental communication satellite on board the second developmental test flight of India's GSLV. |
| GSAT-3 | - | EduSat | 74° East | 20 September 2004 | GSLV Mk I F01 | 1,950 kg (4,300 lb) | Decommissioned (30 September 2010) | Built exclusively to serve the educational sector. It was mainly intended to meet the demand for an interactive satellite-based distance education system for the country. |
| GSAT-4 | - | HealthSat | 82° East | 15 April 2010 | GSLV Mk II D3 | 2,220 kg (4,890 lb) | Failed to orbit | Experimental communication and navigation satellite; maiden flight of the GSLV Mk.II rocket. |
| GSAT-5 | INSAT-4D | | | | GSLV Mk II | 2,250 kg (4,960 lb) | Cancelled | Rebuilt as the GSAT-5P. |
| GSAT-5P | - | | 55° East | 25 December 2010 | GSLV Mk I F06 | 2,310 kg (5,090 lb) | Failed to orbit | As a replacement for INSAT-3E. |
| GSAT-6 | INSAT-4E | | 83° East | 27 August 2015 | GSLV Mk II D6 | 2,132 kg (4,700 lb) | In service | A multimedia mobile satellite system; will offer a Satellite Digital Multimedia Broadcasting (S-DMB) service, via mobile phones and mobile video/audio receivers for vehicles; can also be utilized for strategic and social applications. |
| GSAT-6A | - | | | 29 March 2018 | GSLV Mk II F08 | 2,140 kg (4,720 lb) | Communication lost | Communication with the satellite was lost after the second orbit raising manoeuvre. Efforts are on to re-establish link but at this point it remains incommunicado. |
| GSAT-7 | INSAT-4F | Rukmani | 74° East | 30 August 2013 | Ariane 5 ECA VA-215 | 2,650 kg (5,840 lb) | In service | According to defense experts, to enable the Indian Navy to acquire blue water capabilities and remove dependence on foreign satellites like Inmarsat, which provide communication services to its ships. |
| GSAT-7A | - | Angry Bird | | 19 December 2018 | GSLV Mk II F11 | 2,250 kg (4,960 lb) | In service | GSAT-7A is an advanced military communications satellite meant exclusively for the Indian Air Force. |
| GSAT-7B | - | | | 20XX | GSLV Mk II F? | | Planned | Military communication satellite for Indian Army |
| GSAT-7C | - | | | 20XX | GSLV Mk II F? | | Planned | Military communication satellite for Indian Air Force |
| GSAT-7S | - | | | 20XX | GSLV Mk II | | Planned | Military communication satellite for Indian Air Force |
| GSAT-7R | - | | | 20XX | GSLV Mk II F? | | Planned | Replacement for GSAT-7 Rukmini for Indian Navy |
| GSAT-8 | INSAT-4G | GramSat 8 | 55° East | 20 May 2011 | Ariane 5 ECA VA-202 | 3,093 kg (6,819 lb) | In service | To augment the capacity in the INSAT system; the GAGAN payload provides the Satellite Based Augmentation System (SBAS), through which the accuracy of the positioning information obtained from the IRNSS satellites is improved by a network of ground-based receivers and made available to users in the country through the geostationary satellites. |
| GSAT-9 | - | South Asia Satellite | 48° East | 5 May 2017 | GSLV Mk II F09 | 2,330 kg (5,140 lb) | In service | Carried GAGAN navigation payload, a regional NAVIC navigational system developed by India, that provides navigational services to the security forces and air traffic control organizations. |
| GSAT-10 | - | | 83° East | 29 September 2012 | Ariane 5 ECA VA-209 | 3,435 kg (7,573 lb) | In service | To augment telecommunication, direct-to-home and radio navigation services. |
| GSAT-11 | - | | 74° East | 4 December 2018 | Ariane 5 ECA VA-246 | 5854 kg (12,906 lb) | In service | Aimed at providing advanced telecom and direct-to-home services in the country. Heaviest satellite built by India. |
| GSAT-12 | - | GramSat 12 | 83° East | 15 July 2011 | PSLV-XL C17 | 1,412 kg (3,113 lb) | Decommissioned (March 2023) | Replacement of the INSAT-3B; to provide services like tele-education, telemedicine, disaster management support and satellite internet access. Only GSAT satellite to be launched by PSLV. |
| GSAT-12R | - | CMS-01 | 83° East | 17 December 2020 | PSLV-XL C50 | 1,425 kg (3,142 lb) | In Service | Replacement satellite of GSAT-12. |
| GSAT-14 | - | | 75° East | 5 January 2014 | GSLV Mk.II D5 | 1,982 kg (4,370 lb) | In service | To replace the GSAT-3 satellite; launched by a GSLV Mk.II, which incorporated an Indian-built cryogenic engine on the third stage. |
| GSAT-15 | - | | 93.5° East | 10 November 2015 | Ariane 5 ECA VA-227 | 3,100 kg (6,800 lb) | In service | Similar to GSAT-10 satellite; to augment the capacity of transponders to provide more bandwidth for direct-to-home television and VSAT services. |
| GSAT-16 | - | | 55° East | 6 December 2014 | Ariane 5 ECA VA-221 | 3,150 kg (6,940 lb) | In service | The communication payloads provide a combination of total 48 transponders across the three frequency bands (24 in Normal C band, 12 in Extended-C band and 12 in K$_u$-band) along with a K$_u$-band beacon transmitter, which is the highest for an Indian satellite. The spacecraft will be co-located with GSAT-8 at 55 deg E. |
| GSAT-17 | - | | 93.5° East | 28 June 2017 | Ariane 5 ECA VA-238 | 3,477 kg (7,551 lb) | In service | Payload includes 24 C-band, 2 lower C-band, 12 upper C-band, 2 CxS (C-band up/S-band down), and 1 SxC (S-band up/C-band down) transponders as well as a dedicated transponder for data relay (DRT) and search-and-rescue (SAR) services. |
| GSAT-18 | - | | 74° East | 5 October 2016 | Ariane 5 ECA VA-231 | 3,404 kg (7,505 lb) | In service | To provide services in Normal C-band, Upper Extended C-band and K$_u$ bands of the frequency spectrum. |
| GSAT-19 | - | | 48° East | 5 June 2017 | LVM3 D1 | 3,136 kg (6,914 lb) | In service | Maiden (developmental) flight of GSLV Mark III |
| GSAT-20 | - | CMS-03 GSAT-N2 | 55° East | 18 November 2024 | Falcon 9 Block 5 F9-398 | 5,300 kg (11,684 lb) | In Service | |
| GSAT-22 | - | | | 2024 | LVM3 | | Planned | |
| GSAT-23 | - | | | 2024 | LVM3 | | Planned | |
| GSAT-24 | - | CMS-02 GSAT-N1 | 48° East | 22 June 2022 | Ariane 5 ECA VA-257 | 4,181 kg (9,218 lb) | In Service | |
| GSAT-29 | - | | 55° East | 14 November 2018 | LVM3 D2 | 3,423 kg (7,546 lb) | In service | Second developmental flight of GSLV Mark III |
| GSAT-30 | | | 83° East | 17 January 2020 | Ariane 5 ECA VA-251 | 3,547 kg (7,820 lb) | In Service | Replacement satellite for INSAT-4A |
| GSAT-31 | | | 48° East | 6 February 2019 | Ariane 5 ECA VA-247 | 2,535 kg (5,589 lb) | In Service | |
| GSAT-32 | | GSAT-N3 | | Q1 2025 | LVM3 | 4,500 kg (9,900 lb) | Planned | Replacement of GSAT–6A. |