The Indian National Satellite System or INSAT, is a series of multipurpose geostationary satellites launched by the

Indian Space Research Organisation The Indian Space Research Organisation (ISRO ) is India's national List of government space agencies, space agency, headquartered in Bengaluru, Karnataka. It serves as the principal research and development arm of the Department of Space (DoS), ...

(ISRO) to satisfy

telecommunications Telecommunication, often used in its plural form or abbreviated as telecom, is the transmission of information over a distance using electronic means, typically through cables, radio waves, or other communication technologies. These means of ...

broadcasting Broadcasting is the data distribution, distribution of sound, audio audiovisual content to dispersed audiences via a electronic medium (communication), mass communications medium, typically one using the electromagnetic spectrum (radio waves), ...

meteorology Meteorology is the scientific study of the Earth's atmosphere and short-term atmospheric phenomena (i.e. weather), with a focus on weather forecasting. It has applications in the military, aviation, energy production, transport, agricultur ...

, and

search and rescue Search and rescue (SAR) is the search for and provision of aid to people who are in distress or imminent danger. The general field of search and rescue includes many specialty sub-fields, typically determined by the type of terrain the search ...

operations. Commissioned in 1983, INSAT is the largest domestic communication system in the

Indo-Pacific The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...

Region. It is a joint venture of the Department of Space,

Department of Telecommunications The Department of Telecommunications, abbreviated to DoT, is a department of the Ministry of Communications of the executive branch of the Government of India The Government of India (ISO 15919, ISO: Bhārata Sarakāra, legally the Union ...

India Meteorological Department India Meteorological Department (IMD) is an Indian agency of the Ministry of Earth Sciences of the Government of India. It is the principal agency responsible for meteorological observations, weather forecasting and seismology. IMD is headquar ...

All India Radio All India Radio (AIR), also known as Akashvani (), is India's state-owned public broadcasting, public radio broadcaster. Founded in 1936, it operates under the Ministry of Information and Broadcasting (India), Ministry of Information and Broa ...

and

Doordarshan Doordarshan (), abbreviated as DD, is India's State-owned enterprise, state-owned public broadcasting, public television broadcaster. Established by the Government of India on 15 September 1959, it is owned by the Ministry of Information and B ...

. The overall coordination and management of INSAT system rests with the Secretary-level INSAT Coordination Committee. INSAT satellites provide

transponder In telecommunications, a transponder is a device that, upon receiving a signal, emits a different signal in response. The term is a blend of ''transmitter'' and ''responder''. In air navigation or radio frequency identification, a flight trans ...

s in various bands to serve the television and communication needs of India. Some of the satellites also have the Very High Resolution Radiometer (VHRR), CCD

camera A camera is an instrument used to capture and store images and videos, either digitally via an electronic image sensor, or chemically via a light-sensitive material such as photographic film. As a pivotal technology in the fields of photograp ...

s for

meteorological Meteorology is the scientific study of the Earth's atmosphere and short-term atmospheric phenomena (i.e. weather), with a focus on weather forecasting. It has applications in the military, aviation, energy production, transport, agriculture ...

imaging. The satellites also incorporate transponder(s) for receiving distress alert signals for search and rescue missions in the

South Asia South Asia is the southern Subregion#Asia, subregion of Asia that is defined in both geographical and Ethnicity, ethnic-Culture, cultural terms. South Asia, with a population of 2.04 billion, contains a quarter (25%) of the world's populatio ...

n and

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or approximately 20% of the water area of Earth#Surface, Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia (continent), ...

Region, as ISRO is a member of the Cospas-Sarsat program.

INSAT system

The Indian National Satellite (INSAT) system was commissioned with the launch of INSAT-1B in August 1983 ( INSAT-1A, the first satellite was launched in April 1982 but could not fulfil the mission). INSAT system ushered in a revolution in India's

television Television (TV) is a telecommunication medium for transmitting moving images and sound. Additionally, the term can refer to a physical television set rather than the medium of transmission. Television is a mass medium for advertising, ...

and

radio Radio is the technology of communicating using radio waves. Radio waves are electromagnetic waves of frequency between 3 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmitter connec ...

broadcasting,

telecommunication Telecommunication, often used in its plural form or abbreviated as telecom, is the transmission of information over a distance using electronic means, typically through cables, radio waves, or other communication technologies. These means of ...

s and

sectors. It enabled the rapid expansion of TV and modern telecommunication facilities to even the remote areas and off-shore islands. Together, the system provides transponders in C, Extended C and K_u bands for a variety of communication services. Some of the INSATs also carry instruments for meteorological observation and data relay for providing meteorological services. KALPANA-1 is an exclusive meteorological satellite. The satellites are monitored and controlled by Master Control Facilities that exist in Hassan and

Bhopal Bhopal (; ISO 15919, ISO: Bhōpāl, ) is the capital (political), capital city of the Indian state of Madhya Pradesh and the administrative headquarters of both Bhopal district and Bhopal division. It is known as the ''City of Lakes,'' due to ...

List of INSAT Satellite

This is a total list of INSAT satellites with their outcome.

Satellites in service

Of the 24 satellites launched in the course of the INSAT program, 11 are still in operation.

INSAT-2E

It is the last of the six five satellites in INSAT-2 series. It carries seventeen C-band and lower extended C-band transponders providing zonal and global coverage with an Effective Isotropic Radiated Power (EIRP) of 36 dBW. It also carries a Very High Resolution Radiometer (VHRR) with imaging capacity in the visible (0.55–0.75 μm), thermal infrared (10.5–12.5 μm) and water vapour (5.7–7.1 μm) channels and provides 2x2 km, 8x8 km ground resolution respectively. In addition to the above two payloads it has with it a

CCD camera A charge-coupled device (CCD) is an integrated circuit containing an array of linked, or coupled, capacitors. Under the control of an external circuit, each capacitor can transfer its electric charge to a neighboring capacitor. CCD sensors are a ...

providing km ground resolution in the Visible (0.63–0.69 μm), Near Infrared (0.77–0.86 μm) and Shortwave Infrared (1.55–1.70 μm) bands.

INSAT-3A

The multipurpose satellite, INSAT-3A, was launched by Ariane in April 2003. It is located at 93.5 degree East longitude. The payloads on INSAT-3A are as follows: *12 Normal C-band transponders (9 channels provide expanded coverage from Middle East to South East Asia with an EIRP of 38 dBW, 3 channels provide India coverage with an EIRP of 36 dBW and 6 Extended C-band transponders provide India coverage with an EIRP of 36 dBW). *6 K_u band transponders provide India coverage with EIRP of 48 dBW. * Very High Resolution Radiometer (VHRR) with imaging capacity in the visible (0.55–0.75 μm), infrared (10.5–12.5 μm) and water vapour (5.7–7.1 μm) channels, provide 2x2 km, 8x8 km and 8x8 km ground resolutions respectively. *A CCD camera provides 1x1 km ground resolution, in the visible (0.63–0.69 μm), near infrared (0.77–0.86 μm) and shortwave infrared (1.55–1.70 μm) bands. *A Data Relay Transponder (DRT) having global receive coverage with a 400 MHz uplink and 4500 MHz downlink for relay of meteorological, hydrological and oceanographic data from unattended land and ocean-based automatic data collection-cum-transmission platforms. *A Satellite Aided Search and Rescue (SAS&R) SARP payload having global receive coverage with 406 MHz uplink and 4500 MHz downlink with India coverage, for relay of signals from distress beacons in sea, air or land. See also Cospas-Sarsat.

INSAT-3C

Launched in January 2002, INSAT-3C is positioned at 74 degree East longitude. INSAT-3C payloads include 24 Normal C-band transponders providing an EIRP of 37 dBW, six Extended C-band transponders with EIRP of 37 dBW, two S-band transponders to provide BSS services with 42 dBW EIRP and an MSS payload similar to that on INSAT-3B. All the transponders provide coverage over India.

INSAT-3D

Launched in July 2013, INSAT-3D is positioned at 82 Degree East longitude. INSAT-3D payloads include Imager, Sounder, Data Relay Transponder and Search & Rescue Transponder. All the transponders provide coverage over large part of the Indian Ocean region covering India, Bangladesh, Bhutan, Maldives, Nepal, Seychelles, Sri Lanka and Tanzania for rendering distress alert services.

INSAT-3DR

INSAT-3DR is a weather satellite meant to provide meteorological services to India using a 6-channel imager and a 19-channel sounder, it was launched on 9 September 2016 by the GSLV Mk II F05, and is a follow-up to INSAT-3D.

INSAT-3E

Launched in September 2003, INSAT-3E is positioned at 55 degree East longitude and carries 24 Normal C-band transponders provide an edge of coverage EIRP of 37 dBW over India and 12 Extended C-band transponders provide an edge of coverage EIRP of 38 dBW over India. The satellite has been decommissioned and gone out of service from April 2014. GSAT-16 will replace this satellite.

KALPANA-1

KALPANA-1 is an exclusive meteorological satellite launched by PSLV in September 2002. It carries Very High Resolution Radiometer and DRT payloads to provide meteorological services. It is located at 74 degree East longitude. Its first name was METSAT. It was later renamed as KALPANA-1 to commemorate

Kalpana Chawla Kalpana Chawla (March 17, 1962 – February 1, 2003) was an American astronaut and aerospace engineer who was the first woman of Indian origin to fly to space. Chawla expressed an interest in aerospace engineering from an early age and took engi ...

INSAT-4 Series

INSAT-4A

Launched in December 2005 by the European Ariane launch vehicle, INSAT-4A is positioned at 83 degree East longitude along with INSAT-2E and INSAT-3B. INSAT-A carries 12 K_u band 36 MHz bandwidth transponders employing 140 W TWTAs to provide an EIRP of 52 dBW at the edge of coverage polygon with footprint covering Indian main land and 12 C-band 36 MHz bandwidth transponders provide an EIRP of 39 dBW at the edge of coverage with expanded radiation patterns encompassing Indian geographical boundary, area beyond India in southeast and northwest regions. Tata Sky, a

joint venture A joint venture (JV) is a business entity created by two or more parties, generally characterized by shared ownership, shared returns and risks, and shared governance. Companies typically pursue joint ventures for one of four reasons: to acce ...

between the

TATA Group The Tata Group () is an Indian multinational conglomerate group of companies headquartered in Mumbai. Established in 1868, it is India's largest business conglomerate, with products and services in over 160 countries, and operations in 100 c ...

and

STAR A star is a luminous spheroid of plasma (physics), plasma held together by Self-gravitation, self-gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night sk ...

uses INSAT-4A for distributing their DTH service.

INSAT-4B

It was launched in March 2007 by the European Ariane launch vehicle. Configured with payloads identical to that of INSAT-4A, INSAT-4B carries 12 K_u band and 12 C-band transponders to provide EIRP of 52 dBW and 39 dBW respectively. Two Tx/Rx dual grid offset fed shaped beam reflectors of 2.2 m diameter for K_u band and 2 m diameter for C-band are used. INSAT-4B augments the high power transponder capacity over India in K_u band and over a wider region in C-band. It is co-located with INSAT-3A at 93.5 degree E longitude. The national space agency Indian Space Research Organisation (ISRO) has allotted nearly seven K_u band transponders to Sun Direct; a DTH service provider from South India, and the other five to Doordarshan's DD Direct Plus. 12 transponders in the C band are for TV, radio and telecommunication purposes. The satellite was decommissioned on 24 January 2022. The satellite was moved to a disposal orbit, 340 km above geostationary orbit.

= China-Stuxnet Connection

= American cyber warfare expert Jeffrey Carr, who specialises in investigations of cyber attacks against government, mentioned in his interview with The Times of India, that the reason for this power glitch may have been an infection by the sophisticated

Stuxnet Stuxnet is a Malware, malicious computer worm first uncovered on June 17, 2010, and thought to have been in development since at least 2005. Stuxnet targets supervisory control and data acquisition (SCADA) systems and is believed to be responsibl ...

worm. He attributed the development of Stuxnet worm most likely to Government of China which had the necessary sophistication to develop the bug and would gain the maximum by failure of Indian satellite. He also pointed out that Stuxnet was discovered just a month before the Indian satellite was hit by the power glitch, the reason for which still remains unknown. ISRO uses the same Siemens software that was targeted by Stuxnet.

INSAT-4CR

INSAT-4CR was launched on 2 September 2007 by GSLV-F04. It is a replacement satellite of INSAT-4C which was lost when GSLV-F02 failed and had to be destroyed on its course. It carries 12 K_u band 36 MHz bandwidth transponders employing 140 W TWTAs to provide an Effective Isotropic Radiated Power of 51.5 dBW at Edge of Coverage with footprint covering Indian mainland. It also incorporates a K_u band Beacon as an aid to tracking the satellite. On 8 September 2007 ISRO reported the satellite had reached a near geosynchronous orbit, and would be stabilized in its intended orbital position of 74 degrees E longitude by 15 September. The satellite is designed for a mission life in of ten years. There were reports that the mission life of the satellite had decreased by five years as the thrusters had to burn this much fuel to restore the satellite to its correct orbit. However, the ISRO later refuted this claim dismissing it as false.

GSAT Series

The GSAT satellites are India's indigenously developed communications satellites, used for digital audio, data and video broadcasting for both military and civilian users. As of November 2018, 19 GSAT satellites of ISRO have been launched out of which 15 satellites are currently in service.

GSAT-2

Launched by the second flight of GSLV in May 2003, GSAT-2 is located at 48 degree East longitude and carries four Normal C-band transponders to provide 36 dBW EIRP with India coverage, two K_u band transponders with 42 dBW EIRP over India and an MSS payload similar to those on INSAT-3B and INSAT-3C.

GSAT-3

Configured for audio-visual medium employing digital interactive classroom lessons and multimedia content, GSAT-3 (EDUSAT) was launched by a GSLV in September 2004. Its transponders and their ground coverage are specially configured to cater to the educational requirements. The satellite carries a K_u band transponder covering the Indian mainland region with 50 dBW EIRP, five K_u band spot beam transponders for south, west, central, north and north-east regional coverage with 55 dBW EIRP and six Extended C-band transponders with India coverage with 37 dBW EIRP. EDUSAT is positioned at 74 degree East longitude and is collocated with KALPANA-1 and INSAT-3.

GSAT-6

GSAT-6 (also called INSAT-4E) is a multimedia communication satellite that offers 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.

GSAT-7

GSAT-7 (or INSAT-4F) is a multi-band military communications satellite developed by ISRO. The Indian Navy is the user of the multi-band communication spacecraft, which has been operational since September 2013.

GSAT-8

GSAT-8 (INSAT-4G), is a high power communication satellite in the INSAT system. Weighing about 3,100 kg at lift-off, GSAT-8 is configured to carry 24 high power transponders

Ku band The Ku band () is the portion of the electromagnetic spectrum in the microwave range of frequencies from 12 to 18 gigahertz (GHz). The symbol is short for "K-under" (originally ), because it is the lower part of the original NATO K ban ...

and a two-channel GPS Aided Geo Augmented Navigation (GAGAN) payload operating in L1 and L5 bands.

GSAT 9

The GSAT-9, also known as the "South Asia Satellite", is a

geostationary A geostationary orbit, also referred to as a geosynchronous equatorial orbit''Geostationary orbit'' and ''Geosynchronous (equatorial) orbit'' are used somewhat interchangeably in sources. (GEO), is a circular geosynchronous orbit in altitud ...

communications satellite and meteorology satellite operated by the ISRO for the

South Asian Association for Regional Cooperation The South Asian Association for Regional Cooperation (SAARC) is the regional intergovernmental organization and geopolitical union of states in South Asia. Its member states are Afghanistan, Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, ...

(SAARC) region. The satellite was launched on 5 May 2017.

GSAT-10

GSAT-10 was launched by Ariane-5ECA carrier rocket in 2012. It serves with C and Ku band transponders, and includes a navigation payload to augment GAGAN capacity.

GSAT-12

GSAT-12 configured to carry 12 Extended C-band transponders to meet the country's growing demand for transponders in a short turn-around-time. The 12 Extended C-band transponders of GSAT-12 will augment the capacity in the INSAT system for various communication services like Tele-education, Telemedicine and for Village Resource Centres (VRC). It weighs about at lift-off.

GSAT-14

GSAT-14 was launched in January 2014 to replace the GSAT-3 satellite, which was launched in 2004.

GSAT-15

GSAT-15 is similar to GSAT-10 and is used to augment the capacity of transponders to provide more bandwidth for Direct-to-Home television and VSAT services. It was successfully launched on 10 November 2015 at 21:34:07 UTC aboard an

Ariane 5 Ariane 5 is a retired European heavy-lift space launch vehicle operated by Arianespace for the European Space Agency (ESA). It was launched from the Guiana Space Centre (CSG) in French Guiana. It was used to deliver payloads into geostationar ...

rocket, along with the ArabSat 6B satellite.

GSAT-16

GSAT-16 is the 11th Indian communication satellite meant to increase the number of transponders that in turn enhance the satellite based telecommunication, television, VSAT services in India. GSAT-16 was launched on 7 December 2014 from the Guiana Space Centre, French Guiana, by an Ariane 5 rocket.

GSAT-17

it carries 24 C-band, 2 lower C-band, 12 upper C-band, 2 CxS (C-band up/

S-band The S band is a designation by the Institute of Electrical and Electronics Engineers (IEEE) for a part of the microwave band of the electromagnetic spectrum covering frequencies from 2 to 4 gigahertz (GHz). Thus it crosses the convention ...

down), and 1 SxC (S-band up/C-band down) transponders. It additionally carries a dedicated transponder for data relay (DRT) and search-and-rescue (SAR) services. At the time of launch, GSAT-17 was the heaviest satellite built by ISRO. The satellite was launched on 28 June 2017 aboard an

Ariane 5 ECA Ariane 5 is a retired European Heavy-lift launch vehicle, heavy-lift space launch vehicle operated by Arianespace for the European Space Agency (ESA). It was launched from the Guiana Space Centre (CSG) in French Guiana. It was used to deliver p ...

rocket from the

Guiana Space Centre The Guiana Space Centre (; CSG), also called Europe's Spaceport, is a spaceport to the northwest of Kourou in French Guiana, an Overseas departments and regions of France, overseas region of France in South America. Kourou is located approxim ...

in Kourou, French Guiana.

GSAT-18

GSAT-18 carries 24 C-band, 12 extended C-band, and 12 K_u-band transponders. It was launched on 5 October 2016 aboard an

rocket from the

in Kourou, French Guiana.

GSAT-19

Launched on 5 June 2017, GSAT-19 is a communication satellite

testbed A testbed (also spelled test bed) is a platform for conducting rigorous, transparent, and replicable testing of scientific theories, computing tools, and new technologies. The term is used across many disciplines to describe experimental research ...

for the modular I-6K

satellite bus A satellite bus (or spacecraft bus) is the main body and structural component of a satellite or spacecraft, in which the payload and all scientific instruments are held. Bus-derived satellites are less customized than specially-produced satelli ...

, carrying experimental technologies such as

ion thruster An ion thruster, ion drive, or ion engine is a form of electric propulsion used for spacecraft propulsion. An ion thruster creates a cloud of positive ions from a neutral gas by ionizing it to extract some electrons from its atoms. The i ...

s for manoeuvring and stabilisation, active thermal control using thermal radiators, a miniaturised inertial reference unit, indigenously produced

lithium-ion batteries A lithium-ion or Li-ion battery is a type of rechargeable battery that uses the reversible intercalation of Li+ ions into electronically conducting solids to store energy. Li-ion batteries are characterized by higher specific energy, energy ...

, and C-band traveling-wave-tube amplifiers.

GSAT-29

The GSAT-29 is a large high-throughput communication satellite that was launched on 14 November 2018 through the second developmental flight of GSLV Mark III, that placed the satellite into its planned geosynchronous transfer orbit (GTO) over the equator. Apart from its main communication payload in Ka/Ku bands, GSAT-29 hosts few experimental payloads to mature their technology for use in future spacecraft.

Others

* GSAT-7A * GSAT-11 * GSAT-31 * GSAT-30

Commercial Communications satellite

* ExseedSat-1 is the first Indian commercial satellite built by Satellize (formerly known as Exseed Space). It was a communication satellite launched by SpaceX's Falcon-9 rocket on 6 December 2018. * ExseedSat-2 (AISAT) is the second Indian commercial satellite built for Amsat India launched on the fourth stage of the PSLV-C45 mission.

Indian Communication Satellites Launch Log

References

{{Indian space programme ISRO programs * Communications satellite constellations 1983 establishments in India