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Indian National Satellite System

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81-784: The Indian National Satellite System or INSAT , is a series of multipurpose geostationary satellites launched by the Indian Space Research Organisation (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

162-563: 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 providing 1 × 1  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. The multipurpose satellite, INSAT-3A,

243-479: A delta-v of approximately 50 m/s per year. A second effect to be taken into account is the longitudinal drift, caused by the asymmetry of the Earth – the equator is slightly elliptical ( equatorial eccentricity ). There are two stable equilibrium points sometimes called "gravitational wells" (at 75.3°E and 108°W) and two corresponding unstable points (at 165.3°E and 14.7°W). Any geostationary object placed between

324-427: A geostationary transfer orbit (GTO), an elliptical orbit with an apogee at GEO height and a low perigee . On-board satellite propulsion is then used to raise the perigee, circularise and reach GEO. Satellites in geostationary orbit must all occupy a single ring above the equator . The requirement to space these satellites apart, to avoid harmful radio-frequency interference during operations, means that there are

405-431: A geosynchronous equatorial orbit ( GEO ), is a circular geosynchronous orbit 35,786 km (22,236 mi) in altitude above Earth's equator , 42,164 km (26,199 mi) in radius from Earth's center, and following the direction of Earth's rotation . An object in such an orbit has an orbital period equal to Earth's rotational period, one sidereal day , and so to ground observers it appears motionless, in

486-551: A default thrust of 75 kN (17,000 lb f ) but is capable of a maximum thrust of 93.1 kN (20,900 lb f ). In GSLV-F14 mission, a new white coloured C15 stage was introduced which has more environmental-friendly manufacturing processes, better insulation properties and the use of lightweight materials. GSLV rockets using the Russian Cryogenic Stage (CS) are designated as the GSLV Mark I while versions using

567-455: A fixed position in the sky. The concept of a geostationary orbit was popularised by the science fiction writer Arthur C. Clarke in the 1940s as a way to revolutionise telecommunications, and the first satellite to be placed in this kind of orbit was launched in 1963. Communications satellites are often placed in a geostationary orbit so that Earth-based satellite antennas do not have to rotate to track them but can be pointed permanently at

648-415: A geostationary orbit in particular, it ensures that it holds the same longitude over time. This orbital period, T , is directly related to the semi-major axis of the orbit through the formula: where: The eccentricity is zero, which produces a circular orbit . This ensures that the satellite does not move closer or further away from the Earth, which would cause it to track backwards and forwards across

729-576: A geostationary satellite to globalise communications. Telecommunications between the US and Europe was then possible between just 136 people at a time, and reliant on high frequency radios and an undersea cable . Conventional wisdom at the time was that it would require too much rocket power to place a satellite in a geostationary orbit and it would not survive long enough to justify the expense, so early efforts were put towards constellations of satellites in low or medium Earth orbit. The first of these were

810-547: A higher graveyard orbit to avoid collisions. In 1929, Herman Potočnik described both geosynchronous orbits in general and the special case of the geostationary Earth orbit in particular as useful orbits for space stations . The first appearance of a geostationary orbit in popular literature was in October 1942, in the first Venus Equilateral story by George O. Smith , but Smith did not go into details. British science fiction author Arthur C. Clarke popularised and expanded

891-399: A known position) and providing an additional reference signal. This improves position accuracy from approximately 5m to 1m or less. Past and current navigation systems that use geostationary satellites include: Geostationary satellites are launched to the east into a prograde orbit that matches the rotation rate of the equator. The smallest inclination that a satellite can be launched into

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972-408: A large area of the earth's surface, extending 81° away in latitude and 77° in longitude. They appear stationary in the sky, which eliminates the need for ground stations to have movable antennas. This means that Earth-based observers can erect small, cheap and stationary antennas that are always directed at the desired satellite. However, latency becomes significant as it takes about 240 ms for

1053-501: A limited number of orbital slots available, and thus only a limited number of satellites can be operated in geostationary orbit. This has led to conflict between different countries wishing access to the same orbital slots (countries near the same longitude but differing latitudes ) and radio frequencies . These disputes are addressed through the International Telecommunication Union 's allocation mechanism under

1134-406: A signal to pass from a ground based transmitter on the equator to the satellite and back again. This delay presents problems for latency-sensitive applications such as voice communication, so geostationary communication satellites are primarily used for unidirectional entertainment and applications where low latency alternatives are not available. Geostationary satellites are directly overhead at

1215-462: 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

1296-470: Is pump-fed and generates 760 kN (170,000 lb f ) of thrust, with a burn time of 150 seconds. GSLV-D1 used the S125 stage which contained 125 t (123 long tons; 138 short tons) of solid propellant and had a burn time of 100 seconds. All subsequent launches have used enhanced propellant loaded S139 stage. The S139 stage is 2.8 m in diameter and has a nominal burn time of 100 seconds. The GS2 stage

1377-524: Is a class of expendable launch systems operated by the Indian Space Research Organisation (ISRO). GSLV has been used in fifteen launches since 2001. The Geosynchronous Satellite Launch Vehicle (GSLV) project was initiated in 1990 with the objective of acquiring an Indian launch capability for geosynchronous satellites . GSLV uses major components that are already proven in the Polar Satellite Launch Vehicle (PSLV) launch vehicles in

1458-426: Is a communication satellite testbed for the modular I-6K satellite bus , carrying experimental technologies such as ion thrusters for manoeuvring and stabilisation, active thermal control using thermal radiators , a miniaturised inertial reference unit , indigenously produced lithium-ion batteries , and C-band traveling-wave-tube amplifiers . The GSAT-29 is a large high-throughput communication satellite that

1539-600: 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 (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 and a two-channel GPS Aided Geo Augmented Navigation (GAGAN) payload operating in L1 and L5 bands. The GSAT-9, also known as

1620-784: Is a prototype spaceplane concept created by ISRO. For the Orbital return Flight experiment, a modified version of the GSLV mk.II launcher, with the upper Cryogenic Stage replaced with the PS-4 stage from the PSLV is currently in development,as the RLV won't need all the excess energy produced by the CUS . As of 17 February 2024 , rockets from the GSLV family have made 16 launches, resulting in 10 successes, four failures, and two partial failures. All launches have occurred from

1701-566: Is a total list of INSAT satellites with their outcome. 74° East (1983-92) 93° East (1992-93) 55° East 82.5° East 83° East 111.2° East 93.48° East 74° East Of the 24 satellites launched in the course of the INSAT program, 11 are still in operation. 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

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1782-725: 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 . 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

1863-700: 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 . 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

1944-411: Is positioned at 74 degree East longitude and is collocated with KALPANA-1 and INSAT-3. 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 (or INSAT-4F)

2025-653: Is powered by the Vikas engine . It has a diameter of 2.8 m (9 ft 2 in). The third stage of the GSLV Mark II is propelled by the Indian CE-7.5 cryogenic rocket engine while the older defunct Mark I is propelled using a Russian made KVD-1 . It uses liquid hydrogen (LH 2 ) and liquid oxygen (LOX) The Indian cryogenic engine was built at the Liquid Propulsion Systems Centre The engine has

2106-452: Is that of the launch site's latitude, so launching the satellite from close to the equator limits the amount of inclination change needed later. Additionally, launching from close to the equator allows the speed of the Earth's rotation to give the satellite a boost. A launch site should have water or deserts to the east, so any failed rockets do not fall on a populated area. Most launch vehicles place geostationary satellites directly into

2187-403: Is the gravitational constant , (6.674 28 ± 0.000 67 ) × 10  m kg s . The magnitude of the acceleration, a , of a body moving in a circle is given by: where v is the magnitude of the velocity (i.e. the speed) of the satellite. From Newton's second law of motion , the centripetal force F c is given by: As F c = F g , so that Replacing v with the equation for

2268-781: Is typically 70°, and in some cases less. Geostationary satellite imagery has been used for tracking volcanic ash , measuring cloud top temperatures and water vapour, oceanography , measuring land temperature and vegetation coverage, facilitating cyclone path prediction, and providing real time cloud coverage and other tracking data. Some information has been incorporated into meteorological prediction models , but due to their wide field of view, full-time monitoring and lower resolution, geostationary weather satellite images are primarily used for short-term and real-time forecasting. Geostationary satellites can be used to augment GNSS systems by relaying clock , ephemeris and ionospheric error corrections (calculated from ground stations of

2349-408: Is used to provide visible and infrared images of Earth's surface and atmosphere for weather observation, oceanography , and atmospheric tracking. As of 2019 there are 19 satellites in either operation or stand-by. These satellite systems include: These satellites typically capture images in the visual and infrared spectrum with a spatial resolution between 0.5 and 4 square kilometres. The coverage

2430-677: The Missile Technology Control Regime (MTCR) in May 1992. As a result, ISRO initiated the Cryogenic Upper Stage Project in April 1994 and began developing its own cryogenic engine. A new agreement was signed with Russia for 7 KVD-1 cryogenic stages and 1 ground mock-up stage with no technology transfer, instead of 5 cryogenic stages along with the technology and design as per the earlier agreement. These engines were used for

2511-543: The National Aerospace Laboratories ' 1.2m Trisonic Wind Tunnel Facility. The first development flight of the GSLV (Mk I configuration) was launched on 18 April 2001 was a failure as the payload failed to reach the intended orbit parameters. The launcher was declared operational after the second development flight successfully launched the GSAT-2 satellite. During the initial years from the initial launch to 2014

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2592-473: The Radio Regulations . In the 1976 Bogota Declaration , eight countries located on the Earth's equator claimed sovereignty over the geostationary orbits above their territory, but the claims gained no international recognition. A statite is a hypothetical satellite that uses radiation pressure from the sun against a solar sail to modify its orbit. It would hold its location over the dark side of

2673-654: The South Asian and Indian Ocean Region, as ISRO is a member of the Cospas-Sarsat program. 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 and radio broadcasting, telecommunications and meteorological sectors. It enabled

2754-714: The USNS Kingsport docked in Lagos on August 23, 1963. The first satellite placed in a geostationary orbit was Syncom 3 , which was launched by a Delta D rocket in 1964. With its increased bandwidth, this satellite was able to transmit live coverage of the Summer Olympics from Japan to America. Geostationary orbits have been in common use ever since, in particular for satellite television. Today there are hundreds of geostationary satellites providing remote sensing and communications. Although most populated land locations on

2835-430: The centripetal force required to maintain the orbit ( F c ) is equal to the gravitational force acting on the satellite ( F g ): From Isaac Newton 's universal law of gravitation , where F g is the gravitational force acting between two objects, M E is the mass of the Earth, 5.9736 × 10  kg , m s is the mass of the satellite, r is the distance between the centers of their masses , and G

2916-486: The speed of an object moving around a circle produces: where T is the orbital period (i.e. one sidereal day), and is equal to 86 164 .090 54  s . This gives an equation for r : The product GM E is known with much greater precision than either factor alone; it is known as the geocentric gravitational constant μ = 398 600 .4418 ± 0.0008 km s . Hence Geosynchronous Satellite Launch Vehicle Geosynchronous Satellite Launch Vehicle ( GSLV )

2997-589: The "South Asia Satellite", is a geostationary communications satellite and meteorology satellite operated by the ISRO for the South Asian Association for Regional Cooperation (SAARC) region. The satellite was launched on 5 May 2017. 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 configured to carry 12 Extended C-band transponders to meet

3078-591: The CE-7.5, and is capable of launching 2500 kg into geostationary transfer orbit. Previous GSLV vehicles (GSLV Mark I) have used Russian cryogenic engines. For launches from 2018, a 6% increased thrust version of the Vikas engine was developed. It was demonstrated on 29 March 2018 in the GSAT-6A launch second stage. It was used for the four Vikas engines first stage boosters on future missions. A 4m diameter Ogive payload fairing

3159-424: The Earth at a latitude of approximately 30 degrees. A statite is stationary relative to the Earth and Sun system rather than compared to surface of the Earth, and could ease congestion in the geostationary ring. Geostationary satellites require some station keeping to keep their position, and once they run out of thruster fuel they are generally retired. The transponders and other onboard systems often outlive

3240-548: The L40 stage. Subsequent flights of the GSLV used high pressure engines in the strap-on boosters called the L40H. The GSLV uses four L40H liquid strap-on boosters derived from the L37.5 second stage, which are loaded with 42.6 tons of hypergolic propellants ( UDMH and N 2 O 4 ). The propellants are stored in tandem in two independent tanks 2.1 m (6 ft 11 in) diameter. The engine

3321-569: The Secretary-level INSAT Coordination Committee. INSAT satellites provide transponders 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 cameras for meteorological imaging. The satellites also incorporate transponder(s) for receiving distress alert signals for search and rescue missions in

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3402-400: The absence of servicing missions from the Earth or a renewable propulsion method, the consumption of thruster propellant for station-keeping places a limitation on the lifetime of the satellite. Hall-effect thrusters , which are currently in use, have the potential to prolong the service life of a satellite by providing high-efficiency electric propulsion . For circular orbits around a body,

3483-406: The atmosphere. It is discarded when the vehicle reaches an altitude of about 115 km (71 mi). GSLV employs S-band telemetry and C-band transponders for enabling vehicle performance monitoring, tracking, range safety / flight safety and preliminary orbit determination. The Redundant Strap Down Inertial Navigation System/Inertial Guidance System of GSLV housed in its equipment bay guides

3564-458: The collection of artificial satellites in this orbit is known as the Clarke Belt. In technical terminology the orbit is referred to as either a geostationary or geosynchronous equatorial orbit, with the terms used somewhat interchangeably. The first geostationary satellite was designed by Harold Rosen while he was working at Hughes Aircraft in 1959. Inspired by Sputnik 1 , he wanted to use

3645-509: The concept in a 1945 paper entitled Extra-Terrestrial Relays – Can Rocket Stations Give Worldwide Radio Coverage? , published in Wireless World magazine. Clarke acknowledged the connection in his introduction to The Complete Venus Equilateral . The orbit, which Clarke first described as useful for broadcast and relay communications satellites, is sometimes called the Clarke orbit. Similarly,

3726-513: 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 1,410 kg (3,110 lb) at lift-off. GSAT-14 was launched in January 2014 to replace the GSAT-3 satellite, which

3807-472: 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

3888-471: 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 between the TATA Group and STAR uses INSAT-4A for distributing their DTH service. It

3969-659: The equator and appear lower in the sky to an observer nearer the poles. As the observer's latitude increases, communication becomes more difficult due to factors such as atmospheric refraction , Earth's thermal emission , line-of-sight obstructions, and signal reflections from the ground or nearby structures. At latitudes above about 81°, geostationary satellites are below the horizon and cannot be seen at all. Because of this, some Russian communication satellites have used elliptical Molniya and Tundra orbits, which have excellent visibility at high latitudes. A worldwide network of operational geostationary meteorological satellites

4050-474: The equilibrium points would (without any action) be slowly accelerated towards the stable equilibrium position, causing a periodic longitude variation. The correction of this effect requires station-keeping maneuvers with a maximal delta-v of about 2 m/s per year, depending on the desired longitude. Solar wind and radiation pressure also exert small forces on satellites: over time, these cause them to slowly drift away from their prescribed orbits. In

4131-542: The following properties: An inclination of zero ensures that the orbit remains over the equator at all times, making it stationary with respect to latitude from the point of view of a ground observer (and in the Earth-centered Earth-fixed reference frame). The orbital period is equal to exactly one sidereal day. This means that the satellite will return to the same point above the Earth's surface every (sidereal) day, regardless of other orbital properties. For

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4212-455: The form of the S125/S139 solid rocket booster and the liquid-fueled Vikas engine . Due to the thrust required for injecting the satellite in a geostationary transfer orbit (GTO) the third stage was to be powered by a LOX / LH 2 Cryogenic engine which at that time India did not possess or have the technological expertise to build. The aerodynamic characterization research was conducted at

4293-523: The ground. All geostationary satellites have to be located on this ring. A combination of lunar gravity, solar gravity, and the flattening of the Earth at its poles causes a precession motion of the orbital plane of any geostationary object, with an orbital period of about 53 years and an initial inclination gradient of about 0.85° per year, achieving a maximal inclination of 15° after 26.5 years. To correct for this perturbation , regular orbital stationkeeping maneuvers are necessary, amounting to

4374-536: The indigenous Cryogenic Upper Stage (CUS) are designated the GSLV Mark II. All GSLV launches have been conducted from the Satish Dhawan Space Centre in Sriharikota . The first developmental flight of GSLV Mark I had a 129 tonne (S125) first stage and was capable of launching around 1500 kg into geostationary transfer orbit . The second developmental flight replaced the S125 stage with S139. It used

4455-412: The initial flights and were named GSLV Mk I. The 49 m (161 ft) tall GSLV, with a lift-off mass of 415 t (408 long tons; 457 short tons), is a three-stage vehicle with solid, liquid and cryogenic stages respectively. The payload fairing, which is 7.8 m (26 ft) long and 3.4 m (11 ft) in diameter, protects the vehicle electronics and the spacecraft during its ascent through

4536-407: The launcher had a checkered history with only 2 successful launches out of 7, resulting in the rocket gaining the nickname "naughty boy". The third stage was to be procured from Russian company Glavkosmos , including transfer of technology and design details of the engine based on an agreement signed in 1991. Russia backed out of the deal after United States objected to the deal as in violation of

4617-538: The passive Echo balloon satellites in 1960, followed by Telstar 1 in 1962. Although these projects had difficulties with signal strength and tracking, issues that could be solved using geostationary orbits, the concept was seen as impractical, so Hughes often withheld funds and support. By 1961, Rosen and his team had produced a cylindrical prototype with a diameter of 76 centimetres (30 in), height of 38 centimetres (15 in), weighing 11.3 kilograms (25 lb), light and small enough to be placed into orbit. It

4698-476: The planet now have terrestrial communications facilities ( microwave , fiber-optic ), with telephone access covering 96% of the population and internet access 90%, some rural and remote areas in developed countries are still reliant on satellite communications. Most commercial communications satellites , broadcast satellites and SBAS satellites operate in geostationary orbits. Geostationary communication satellites are useful because they are visible from

4779-485: The position in the sky where the satellites are located. Weather satellites are also placed in this orbit for real-time monitoring and data collection, and navigation satellites to provide a known calibration point and enhance GPS accuracy. Geostationary satellites are launched via a temporary orbit , and placed in a slot above a particular point on the Earth's surface. The orbit requires some stationkeeping to keep its position, and modern retired satellites are placed in

4860-624: 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 . This

4941-524: The same plane, altitude and speed; however, the presence of satellites in eccentric orbits allows for collisions at up to 4 km/s. Although a collision is comparatively unlikely, GEO satellites have a limited ability to avoid any debris. At geosynchronous altitude, objects less than 10 cm in diameter cannot be seen from the Earth, making it difficult to assess their prevalence. Despite efforts to reduce risk, spacecraft collisions have occurred. The European Space Agency telecom satellite Olympus-1

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5022-524: The same solid motor with 138 tonne propellant loading. The chamber pressure in all liquid engines were enhanced, enabling a higher propellant mass and burn time. These improvements allowed GSLV to carry an additional 300 kg of payload. The fourth operational flight of GSLV Mark I, GSLV-F06, had a longer third stage called the C15 with 15 tonne propellant loading and also employed a 4 meter diameter payload fairing. This variant uses an Indian cryogenic engine,

5103-496: 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. it carries 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. It additionally carries a dedicated transponder for data relay (DRT) and search-and-rescue (SAR) services. At

5184-412: The satellite to its correct orbit. However, the ISRO later refuted this claim dismissing it as false. 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. Launched by

5265-410: 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

5346-420: 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. Configured for audio-visual medium employing digital interactive classroom lessons and multimedia content, GSAT-3 (EDUSAT)

5427-405: The sky. A geostationary orbit can be achieved only at an altitude very close to 35,786 kilometres (22,236 miles) and directly above the equator. This equates to an orbital speed of 3.07 kilometres per second (1.91 miles per second) and an orbital period of 1,436 minutes, one sidereal day . This ensures that the satellite will match the Earth's rotational period and has a stationary footprint on

5508-485: The thruster fuel and by allowing the satellite to move naturally into an inclined geosynchronous orbit some satellites can remain in use, or else be elevated to a graveyard orbit . This process is becoming increasingly regulated and satellites must have a 90% chance of moving over 200 km above the geostationary belt at end of life. Space debris at geostationary orbits typically has a lower collision speed than at low Earth orbit (LEO) since all GEO satellites orbit in

5589-558: 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 rocket from the Guiana Space Centre in Kourou , French Guiana. 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 Ariane 5 ECA rocket from the Guiana Space Centre in Kourou , French Guiana. Launched on 5 June 2017, GSAT-19

5670-549: The transponders provide coverage over India. 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

5751-499: The vehicle from lift-off to spacecraft injection. The digital auto-pilot and closed loop guidance scheme ensure the required altitude maneuver and guide injection of the spacecraft to the specified orbit. The GSLV can place approximately 5,000 kg (11,000 lb) into an easterly low Earth orbit (LEO) or 2,500 kg (5,500 lb) (for the Mk II version) into an 18° geostationary transfer orbit . The first GSLV flight, GSLV-D1 used

5832-560: Was spin stabilised with a dipole antenna producing a pancake shaped beam. In August 1961, they were contracted to begin building the real satellite. They lost Syncom 1 to electronics failure, but Syncom 2 was successfully placed into a geosynchronous orbit in 1963. Although its inclined orbit still required moving antennas, it was able to relay TV transmissions, and allowed for US President John F. Kennedy in Washington D.C., to phone Nigerian prime minister Abubakar Tafawa Balewa aboard

5913-411: Was decommissioned on 24 January 2022. The satellite was moved to a disposal orbit , 340 km above geostationary orbit. 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 worm. He attributed

5994-582: Was developed and deployed for the first time in the EOS-03 launch on 12 August 2021, although this launch was a failure due to technical anomalies with the Cryogenic Upper Stage. This will allow GSLV vehicles to accommodate larger payloads. As of October 2024, ISRO has stopped selling GSLV Mk II Rockets. Eight Known launches are planned with NVS Missions, IDRSS Missions, NISAR Mission,etc. The Reusable Launch Vehicle Technology Demonstration program ,

6075-463: Was launched by Ariane in April 2003. It is located at 93.5 degree East longitude. The payloads on INSAT-3A are as follows: 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

6156-459: 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

6237-487: Was launched in 2004. 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 rocket, along with the ArabSat 6B satellite. GSAT-16 is the 11th Indian communication satellite meant to increase the number of transponders that in turn enhance

6318-496: 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

6399-506: Was launched on 14 November 2018 through the second developmental flight of GSLV Mark III , that placed the 3,423 kg (7,546 lb) 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. Geostationary satellites A geostationary orbit , also referred to as

6480-431: 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

6561-490: Was struck by a meteoroid on August 11, 1993, and eventually moved to a graveyard orbit , and in 2006 the Russian Express-AM11 communications satellite was struck by an unknown object and rendered inoperable, although its engineers had enough contact time with the satellite to send it into a graveyard orbit. In 2017, both AMC-9 and Telkom-1 broke apart from an unknown cause. A typical geostationary orbit has

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