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58-538: StarBand ceased operations effective September 30, 2015 citing increased competition from other internet providers. The StarBand satellite Internet system was a VSAT platform that used K u band satellites for transmission of data from users' PCs to the StarBand network operations center. Two-way bandwidth for residential users was up to 1.5 Mbit/s download speed and 256 kbit/s upload speed, with unlimited usage and online hours. A 0.75 meter satellite dish

116-483: 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

174-427: 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

232-431: 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

290-449: A consequence it is only 500 mW compared with the normal 2W, thus is poorer in rain. Skylogic's Tooway system also uses an integrated OMT/BUC/LNB assembly called a transmit and receive integrated assembly (TRIA), which is 3W. For large antennas there are also mechanical struts that prevent them to move due to strong winds, losing the pointing and causing service interruption A maritime VSAT has features that allow it to be operated on

348-455: 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

406-415: 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

464-579: 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

522-552: 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

580-399: 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

638-408: 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

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696-516: 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

754-439: A ship at sea. A ship that is underway is in continuous motion in all axes. The antenna part of a marine VSAT system must be stabilized with respect to the horizon and true north as the ship moves beneath it. Motors and sensors are used to keep the antenna pointed accurately at the satellite. This enables it to transmit to and receive from the satellite while minimising losses and interference with adjacent satellites. New technology

812-406: 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

870-550: A third generation .78M antenna, which required a separate antenna to receive satellite television signals. The third generation antenna provided a longer focal length, which helped to create a better signal-to-noise ratio. All satellite internet providers such as StarBand measure the amount of data you transfer. Starband had six plans ranging from 500 kbit/s down to 1500 kbit/s down with weekly download limits of 750 Mbytes to 4,000 Mbytes. Very-small-aperture terminal A very-small-aperture terminal ( VSAT )

928-624: Is a two-way satellite ground station with a dish antenna that is smaller than 3.8 meters. The majority of VSAT antennas range from 75 cm to 1.2 m. Bit rates , in most cases, range from 4 kbit/s to 16 Mbit/s. VSATs access satellites in geosynchronous orbit or geostationary orbit to relay data from small remote Earth stations (terminals) to other terminals (in mesh topology ) or master Earth station "hubs" (in star topology ). VSATs are used to transmit narrowband data (e.g., point-of-sale transactions using credit cards, polling or RFID data, or SCADA ), or broadband data (for

986-450: Is emerging that will allow a solid state device (flat panel) to steer an antenna electronically without moving parts. Initially, stabilized satellite antennas were used on ships for reception of television signals. One of the first companies to manufacture stabilized VSAT antennas was SeaTel of Concord , California , which launched its first stabilized antenna in 1978. SeaTel dominates the supply of two-way VSAT stabilised antenna systems to

1044-420: Is needed; the antenna was sufficiently small that homeowner associations could not prohibit its installation. StarBand Communications Inc. was initially a joint venture between Gilat Satellite Networks , EchoStar and Microsoft , and the StarBand service launched in 2000. StarBand Communications filed for Chapter 11 bankruptcy in 2002 and emerged from bankruptcy in 2003. In March 2005, StarBand Communications

1102-452: 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

1160-403: 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

1218-781: 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

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1276-408: 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

1334-481: 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

1392-732: 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

1450-430: 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

1508-682: The price–performance ratio of fixed satellite service (FSS) over the past five years. New VSAT systems are coming online using K a band technology that promise higher data rates for lower costs. FSS systems currently in orbit have a huge capacity with a relatively low price structure. FSS systems provide various applications for subscribers, including: telephony , fax , television , high-speed data communication services, Internet access, satellite news gathering (SNG), Digital Audio Broadcasting (DAB) and others. These systems provide high-quality service because they create efficient communication systems for both residential and business users. All

1566-424: 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

1624-417: The Earth's rotational period, making it appear to hover over a fixed point on the Earth's equator . Arthur C. Clarke's October 1945 Wireless World article (called "Extra-Terrestrial Relays: Can Rocket Stations Give World-wide Radio Coverage?") discussed the necessary orbital characteristics for a geostationary orbit and the frequencies and power needed for communication. Live satellite communication

1682-466: The Gilat SkyEdge series). The StarBand Nova modems were capable of higher speeds, optimized for VoIP, VPN, and worked on a more efficient hub. The SkyEdge modems had one Ethernet port and did not require hosting software for any OS platform. Initially, StarBand supplied a .76M convergence antenna, which picked up two Dish Network signals and the satellite internet signal. StarBand later supplied

1740-604: The Model 480 modem (based on the Gilat Skystar 360E VSAT), which connected via Ethernet, supported multiple computers/OSes and required no additional software. The 48x series service supported Microsoft Windows PC , Macintosh , Unix and Linux computers. In late 2005, StarBand began selling only Model 480-based services. In October 2006, StarBand introduced its next-generation service, the StarBand Nova (based on

1798-601: The StarBand Model 180 (based on the Gilat Skystar Advantage/180 VSAT) connected via USB. The 180 modem was Windows OS-only because it required specialized Windows drivers for the USB interface. In 2002, StarBand switched to Gilat's Model 360 VSAT, which enabled higher speed and allowed USB or Ethernet connections, but still required driver software to communicate. In 2003, StarBand introduced

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1856-400: 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,

1914-464: 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

1972-520: 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,

2030-585: The early 1980s. Equatorial later developed a C band (4/6 GHz) two-way system using 1 m x 0.5 m antennas and sold about 10,000 units in 1984–85. In the early 1980s, LINKABIT (the predecessor to Qualcomm and ViaSat) developed the world's first Ku-band (12–14 GHz) VSAT for Schlumberger to provide network connectivity for oil field drilling and exploration units. LINKABIT which had become part of M/A-COM went on to develop K u band VSATs for enterprise customers such as Walmart , Holiday Inn , Chrysler , and General Motors . These enterprise terminals made up

2088-551: The entry-level cost for getting maritime VSAT installed, which turned out to be of key importance to small to mid-sized fleets, and thus to the market acceptance of VSAT. According to the Maritime VSAT report issued by the Comsys Group, the market for stabilised maritime VSAT services (not including oil and gas rigs) reached more than $ 400 million in 2007. In 2010, COMSYS released its "2nd Maritime VSAT Report", where

2146-659: 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

2204-474: 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

2262-553: 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

2320-523: 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

2378-654: The highest capacity satellite ever, ViaSat-1, in 2011 to expand the WildBlue base under its Exede brand. In 2007, Hughes Communications started deploying K a band VSAT sites for consumers under its HughesNet brand on the Spaceway 3 satellite and later in 2012 on its EchoStar XVII/Jupiter 1 satellite. By September 2014, Hughes became the first Satellite Internet Provider to surpass one million active terminals. Most VSAT networks are configured in one of these topologies : Advances in technology have dramatically improved

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2436-734: The horizon, with new constellations slated to come online before 2020. StarBand offered the first residential two-way satellite Internet service in the United States market. Launched in November 2000, StarBand began selling the Gilat Satellite Networks SkyBlaster PCI card VSAT . Initially, the only way to purchase the StarBand system was to purchase a PC with the send/receive adapter card pre-installed as well as hosting software. In 2001, StarBand began offering service using standalone VSAT units using

2494-547: The major providers have branded their maritime VSAT offerings such that Vizada offers its service through the Marlink division and the SeaLink and WaveCall products, OmniAccess, through their BroadBEAM products and Ship Equip calls its offering Sevsat . VSAT Maritime Connectivity Service Providers Market Shares Global - Revenues (2018 & 2019): Geostationary orbit A geostationary orbit , also referred to as

2552-515: The marine industry with almost 72% of the market in 2007 compared to Orbit's 17.6%. Initially, maritime VSAT was using single channel per carrier technology, which suited large-volume users like oil drilling rigs and oil platforms and large fleets of ships from one shipowner sailing within one or few satellite footprints . This changed when the company iDirect launched its IP-based time-division multiple access technology that dynamically allocated bandwidth to each ship for shared bandwidth, lowering

2610-687: The market estimate had increased to $ 590 million in 2009 with predictions for 2010 at $ 850 million. The estimated size of the market in terms of vessels eligible to get VSAT was in this report set to in excess of 42,000 with just over 34,000 to go. The major companies market share in terms of number of vessels in service were in 2009 (2007 in parentheses) according to these reports: Vizada: 17.6% (26.0%), Ship Equip: 11.0% (10.7%), Cap Rock 2.8% (2.9%), MTN 7.5% (6.4%), Stratos - % (3.6%), KVH 5.4% (- %) Elektrikom 4.9% (3.2%), Intelsat 3.4% (- %), Eutelsat 3.1%, NSSL 3.1%, Radio Holland 3.0%, Telemar 3.0%, DTS 2.6% and others accounted for 32.6% (27.7%). Many of

2668-450: The outdoor parts on the dish are collectively called the ODU (Outdoor Unit), i.e., OMT to split signal between BUC and LNB. The IDU is effectively a modem, usually with Ethernet port and 2 x F-connectors for the coax to BUC (Transmit) and from LNB (Receive). The Astra2Connect has an all-in-one OMT/BUC/LNA that looks like a Quad LNB in shape and size which mounts on a regular TV satellite mount. As

2726-538: 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

2784-476: 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

2842-485: 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

2900-636: The provision of satellite Internet access to remote locations, VoIP or video). VSATs are also used for transportable, on-the-move (utilising phased array antennas) or mobile maritime communications. The concept of the geostationary orbit was originated by Russian theorist Konstantin Tsiolkovsky , who wrote articles on space travel around the beginning of the 20th century. In the 1920s, Hermann Oberth and Herman Potocnik , also known as Herman Noordung, described an orbit at an altitude of 35,900 kilometres (22,300 miles) whose period exactly matched

2958-524: 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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3016-405: 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

3074-485: 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

3132-486: The vast majority of sites for the next 20 years for two-way data or telephony applications. A large VSAT network, with more than 12,000 sites, was deployed by Spacenet and MCI for the U.S. Postal Service in the 1980s. As of 2015 , the largest VSAT Ku-band network containing over 100,000 VSATs was deployed by and is operated by Hughes Communications for lottery applications. In 2005, WildBlue (now ViaSat) started deploying VSAT networks deploying Ka-band. ViaSat launched

3190-566: 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

3248-616: Was developed in the 1960s by NASA , which launched Syncom 1–3 satellites. Syncom 3 transmitted live coverage of the 1964 Olympics in Japan to viewers in the United States and Europe . On April 6, 1965, the first commercial satellite was launched into space, Intelsat I , nicknamed Early Bird. The first commercial VSATs were C band (6 GHz) receive-only systems by Equatorial Communications using spread spectrum technology. More than 30,000 60 cm antenna systems were sold in

3306-499: 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

3364-472: Was wholly acquired by Spacenet , a division of Gilat Satellite Networks, which continued to operate the service. As of mid-2005, StarBand had approximately 32,000 subscribers. StarBand announced in August 2015 that they would cease operations on 30 September 2015, citing competitive pressures from other current satellite internet providers, as well as new higher-bandwidth providers ( Starlink and OneWeb ) on

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