796:(COMSAT) private corporation, which was subject to instruction by the US Government on matters of national policy. Over the next two years, international negotiations led to the Intelsat Agreements, which in turn led to the launch of Intelsat 1, also known as Early Bird, on 6 April 1965, and which was the first commercial communications satellite to be placed in geosynchronous orbit. Subsequent Intelsat launches in the 1960s provided multi-destination service and video, audio, and data service to ships at sea (Intelsat 2 in 1966–67), and the completion of a fully global network with Intelsat 3 in 1969–70. By the 1980s, with significant expansions in commercial satellite capacity, Intelsat was on its way to become part of the competitive private telecommunications industry, and had started to get competition from the likes of
828:
885:(GEO), which is 22,236 miles (35,785 km) from Earth's surface. This orbit has the special characteristic that the apparent position of the satellite in the sky when viewed by a ground observer does not change, the satellite appears to "stand still" in the sky. This is because the satellite's orbital period is the same as the rotation rate of the Earth. The advantage of this orbit is that ground antennas do not have to track the satellite across the sky, they can be fixed to point at the location in the sky the satellite appears.
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62:
1050:, was launched. It was a medium Earth orbit satellite designed to help facilitate high-speed telephone signals. Although it was the first practical way to transmit signals over the horizon, its major drawback was soon realised. Because its orbital period of about 2.5 hours did not match the Earth's rotational period of 24 hours, continuous coverage was impossible. It was apparent that multiple MEOs needed to be used in order to provide continuous coverage.
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between 2 and 8 hours. MEO satellites have a larger coverage area than LEO satellites. A MEO satellite's longer duration of visibility and wider footprint means fewer satellites are needed in a MEO network than a LEO network. One disadvantage is that a MEO satellite's distance gives it a longer time delay and weaker signal than a LEO satellite, although these limitations are not as severe as those of a GEO satellite.
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continuous communications capability with these lower orbits requires a larger number of satellites, so that one of these satellites will always be visible in the sky for transmission of communication signals. However, due to their closer distance to the Earth, LEO or MEO satellites can communicate to ground with reduced latency and at lower power than would be required from a geosynchronous orbit.
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638:. Military planners had long shown considerable interest in secure and reliable communications lines as a tactical necessity, and the ultimate goal of this project was the creation of the longest communications circuit in human history, with the Moon, Earth's natural satellite, acting as a passive relay. After achieving the first transoceanic communication between
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1600:, where no submarine cables are in service, need satellite telephones. There are also regions of some continents and countries where landline telecommunications are rare to non existent, for example large regions of South America, Africa, Canada, China, Russia, and Australia. Satellite communications also provide connection to the edges of
742:. After an initial failure in 1961, a launch on 9 May 1963 dispersed 350 million copper needle dipoles to create a passive reflecting belt. Even though only about half of the dipoles properly separated from each other, the project was able to successfully experiment and communicate using frequencies in the
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The
Molniya orbit is designed so that the satellite spends the great majority of its time over the far northern latitudes, during which its ground footprint moves only slightly. Its period is one half day, so that the satellite is available for operation over the targeted region for six to nine hours
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The definitions of FSS and DBS satellites outside of North
America, especially in Europe, are a bit more ambiguous. Most satellites used for direct-to-home television in Europe have the same high power output as DBS-class satellites in North America, but use the same linear polarization as FSS-class
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Satellite phone systems can be accomplished by a number of means. On a large scale, often there will be a local telephone system in an isolated area with a link to the telephone system in a main land area. There are also services that will patch a radio signal to a telephone system. In this example,
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In the United States, the
National Polar-orbiting Operational Environmental Satellite System (NPOESS) was established in 1994 to consolidate the polar satellite operations of NASA (National Aeronautics and Space Administration) NOAA (National Oceanic and Atmospheric Administration). NPOESS manages a
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Because of their low altitude, these satellites are only visible from within a radius of roughly 1,000 kilometres (620 mi) from the sub-satellite point. In addition, satellites in low Earth orbit change their position relative to the ground position quickly. So even for local applications, many
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As satellites in MEO and LEO orbit the Earth faster, they do not remain visible in the sky to a fixed point on Earth continually like a geostationary satellite, but appear to a ground observer to cross the sky and "set" when they go behind the Earth beyond the visible horizon. Therefore, to provide
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Molniya orbits can be an appealing alternative in such cases. The
Molniya orbit is highly inclined, guaranteeing good elevation over selected positions during the northern portion of the orbit. (Elevation is the extent of the satellite's position above the horizon. Thus, a satellite at the horizon
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was launched on 4 October 1960 to explore whether it would be possible to establish a global military communications network by using "delayed repeater" satellites, which receive and store information until commanded to rebroadcast them. After 17 days, a command system failure ended communications
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the signal coming from the source, toward the direction of the receiver. With passive satellites, the reflected signal is not amplified at the satellite, and only a small amount of the transmitted energy actually reaches the receiver. Since the satellite is so far above Earth, the radio signal is
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that worked on two frequencies of 20.005 and 40.002 MHz, or 7 and 15 meters wavelength. The satellite was not placed in orbit to send data from one point on Earth to another, but the radio transmitter was meant to study the properties of radio wave distribution throughout the ionosphere. The
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A medium Earth orbit is a satellite in orbit somewhere between 2,000 and 35,786 kilometres (1,243 and 22,236 mi) above the Earth's surface. MEO satellites are similar to LEO satellites in functionality. MEO satellites are visible for much longer periods of time than LEO satellites, usually
1005:
It is also possible to offer discontinuous coverage using a low-Earth-orbit satellite capable of storing data received while passing over one part of Earth and transmitting it later while passing over another part. This will be the case with the CASCADE system of Canada's
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and so are obstructed by the curve of the Earth. The purpose of communications satellites is to relay the signal around the curve of the Earth allowing communication between widely separated geographical points. Communications satellites use a wide range of radio and
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or dish antennas. Due to launch costs, most current amateur satellites are launched into fairly low Earth orbits, and are designed to deal with only a limited number of brief contacts at any given time. Some satellites also provide data-forwarding services using the
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These orbits are Sun synchronous, meaning that they cross the equator at the same local time each day. For example, the satellites in the NPOESS (civilian) orbit will cross the equator, going from south to north, at times 1:30 P.M., 5:30 P.M., and 9:30 P.M.
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The bandwidth available from a satellite depends upon the number of transponders provided by the satellite. Each service (TV, Voice, Internet, radio) requires a different amount of bandwidth for transmission. This is typically known as link budgeting and a
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627:, so the signal received on Earth is very weak. Active satellites, on the other hand, amplify the received signal before retransmitting it to the receiver on the ground. Passive satellites were the first communications satellites, but are little used now.
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active communications satellite was launched on 11 February 1965 to explore the feasibility of active solid-state X band long-range military communications. A total of nine satellites were launched between 1965 and 1976 as part of this series.
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used by DBS satellites), but this is a minor technical difference that users do not notice. FSS satellite technology was also originally used for DTH satellite TV from the late 1970s to the early 1990s in the United States in the form of
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Geostationary satellites must operate above the equator and therefore appear lower on the horizon as the receiver gets farther from the equator. This will cause problems for extreme northerly latitudes, affecting connectivity and causing
661:(ARPA) and launched on 18 December 1958, which used a tape recorder to carry a stored voice message, as well as to receive, store, and retransmit messages. It was used to send a Christmas greeting to the world from U.S. President
522:. To avoid signal interference, international organizations have regulations for which frequency ranges or "bands" certain organizations are allowed to use. This allocation of bands minimizes the risk of signal interference.
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operators have access to amateur satellites, which have been designed specifically to carry amateur radio traffic. Most such satellites operate as spaceborne repeaters, and are generally accessed by amateurs equipped with
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Within these regions, frequency bands are allocated to various satellite services, although a given service may be allocated different frequency bands in different regions. Some of the services provided by satellites are:
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is an equivalent ESA project that is stated to be compatible and providing navigational services for the lunar surface. Both programmes are satellite constellstions of several satellites in various orbits around the Moon.
768:, launched on 19 July 1964, was the first geostationary communications satellite. Syncom 3 obtained a geosynchronous orbit, without a north–south motion, making it appear from the ground as a stationary object in the sky.
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Command and
Control subsystem, which maintains communications with ground control stations. The ground control Earth stations monitor the satellite performance and control its functionality during various phases of its
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signals. Communication signals were bounced off the satellite from one point on Earth to another. This experiment sought to establish the feasibility of worldwide broadcasts of telephone, radio, and television signals.
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technology as a reference, these antennas automatically re-aim to the satellite no matter where or how the vehicle (on which the antenna is mounted) is situated. These mobile satellite antennas are popular with some
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Thus, for areas close to the North (and South) Pole, a geostationary satellite may appear below the horizon. Therefore, Molniya orbit satellites have been launched, mainly in Russia, to alleviate this problem.
819:, with two high apogees daily over the northern hemisphere. This orbit provides a long dwell time over Russian territory as well as over Canada at higher latitudes than geostationary orbits over the equator.
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Typically the orbit of a medium Earth orbit satellite is about 16,000 kilometres (10,000 mi) above Earth. In various patterns, these satellites make the trip around Earth in anywhere from 2 to 8 hours.
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Like LEOs, these satellites do not maintain a stationary distance from the Earth. This is in contrast to the geostationary orbit, where satellites are always 35,786 kilometres (22,236 mi) from Earth.
938:(LEO) typically is a circular orbit about 160 to 2,000 kilometres (99 to 1,243 mi) above the Earth's surface and, correspondingly, a period (time to revolve around the Earth) of about 90 minutes.
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A satellite radio or subscription radio (SR) is a digital radio signal that is broadcast by a communications satellite, which covers a much wider geographical range than terrestrial radio signals.
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A geostationary orbit is useful for communications because ground antennas can be aimed at the satellite without their having to track the satellite's motion. This is relatively inexpensive.
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almost any type of satellite can be used. Satellite phones connect directly to a constellation of either geostationary or low-Earth-orbit satellites. Calls are then forwarded to a satellite
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number of satellites for various purposes; for example, METSAT for meteorological satellite, EUMETSAT for the
European branch of the program, and METOP for meteorological operations.
949:(signal strength falls off as the square of the distance from the source, so the effect is considerable). Thus there is a trade off between the number of satellites and their cost.
1218:, to distribute programming to their local affiliate stations. Satcom 1 was widely used because it had twice the communications capacity of the competing Westar 1 in America (24
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spacecraft in orbit over the
European continent. Because of this, the terms FSS and DBS are more so used throughout the North American continent, and are uncommon in Europe.
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To an observer on Earth, a satellite in a gestationary orbit appears motionless, in a fixed position in the sky. This is because it revolves around the Earth at Earth's own
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Allocating frequencies to satellite services is a complicated process which requires international coordination and planning. This is carried out under the auspices of the
2794:
Ward, William W.; Floyd, Franklin W. (1997). "Chapter 8: Thirty Years of Space
Communications Research and Development at Lincoln Laboratory". In Butrica, Andrew J (ed.).
1680:. They are normally used for broadcast feeds to and from television networks and local affiliate stations (such as program feeds for network and syndicated programming,
1608:. Other land use for satellite phones are rigs at sea, a backup for hospitals, military, and recreation. Ships at sea, as well as planes, often use satellite phones.
764:. It revolved around the Earth once per day at constant speed, but because it still had north–south motion, special equipment was needed to track it. Its successor,
665:. The satellite also executed several realtime transmissions before the non-rechargeable batteries failed on 30 December 1958 after eight hours of actual operation.
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3649:
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1133:, was launched on 6 April 1965 and placed in orbit at 28° west longitude. It was the first geostationary satellite for telecommunications over the Atlantic Ocean.
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2578:
van Keuren, David K. (1997). "Chapter 2: Moon in Their Eyes: Moon
Communication Relay at the Naval Research Laboratory, 1951-1962". In Butrica, Andrew J (ed.).
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Low-Earth-orbiting satellites are less expensive to launch into orbit than geostationary satellites and, due to proximity to the ground, do not require as high
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services in some countries, notably the United States. Mobile services allow listeners to roam a continent, listening to the same audio programming anywhere.
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was the first active, direct relay communications commercial satellite and marked the first transatlantic transmission of television signals. Belonging to
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Operating at lower frequency and lower power than DBS, FSS satellites require a much larger dish for reception (3 to 8 feet (1 to 2.5 m) in diameter for K
1222:
as opposed to the 12 of Westar 1), resulting in lower transponder-usage costs. Satellites in later decades tended to have even higher transponder numbers.
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3354:"DIRECTV's Spaceway F1 Satellite Launches New Era in High-Definition Programming; Next Generation Satellite Will Initiate Historic Expansion of DIRECTV"
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807:, who did not participate in the Intelsat agreements. The Soviet Union launched its first communications satellite on 23 April 1965 as part of the
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Altshuler, José (1997). "Chapter 18: From
Shortwave and Scatter to Satellite: Cuba's International Communications". In Butrica, Andrew J (ed.).
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1763:(usually 18 to 24 inches or 45 to 60 cm in diameter). Direct broadcast satellites generally operate in the upper portion of the microwave
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1700:, and general commercial telecommunications. FSS satellites are also used to distribute national cable channels to cable television headends.
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used to keep the satellite in the right orbit, with its antennas pointed in the right direction, and its power system pointed towards the Sun
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every second revolution. In this way a constellation of three Molniya satellites (plus in-orbit spares) can provide uninterrupted coverage.
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1230:) had built nearly 40 percent of the more than one hundred satellites in service worldwide. Other major satellite manufacturers include
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Region A, Low Earth Orbit (or LEO) Region – spherical region that extends from the Earth's surface up to an altitude (Z) of 2,000 km
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using the satellite. Additionally, it was the first satellite used by broadcast television networks in the United States, like
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distribution, the savings in ground equipment can more than outweigh the cost and complexity of placing a satellite into orbit.
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In addition, there are important differences in the onboard and ground equipment needed to support the two types of missions.
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antennas of ground stations can be aimed permanently at that spot and do not have to move to track the satellite. Others form
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1573:, where they are then transmitted to a geostationary satellite. The downlink follows an analogous path. Improvements in
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launch of Sputnik 1 was a major step in the exploration of space and rocket development, and marks the beginning of the
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via broadband data connections. This can be very useful for users who are located in remote areas, and cannot access a
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There are plans and initiatives to bring dedicated communications satellite beyond geostationary orbits. NASA proposed
503:, where antennas on the ground have to follow the position of the satellites and switch between satellites frequently.
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642:, and Hawaii on 23 January 1956, this system was publicly inaugurated and put into formal production in January 1960.
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of the concept of the communications satellite, and the term 'Clarke Belt' is employed as a description of the orbit.
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1121:, launched on 19 August 1964, and used for communication across the Pacific starting with television coverage of the
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679:'s satellite applications program launched the first artificial satellite used for passive relay communications in
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3107:. INTER-AGENCY SPACE DEBRIS COORDINATION COMMITTEE: Issued by Steering Group and Working Group 4. September 2007.
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Pelton, Joseph N. (2015). "History of Satellite Communications". In Pelton J.; Madry S.; Camacho-Lara S. (eds.).
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in geostationary orbits to relay radio signals. Because of this, Arthur C. Clarke is often quoted as being the
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3210:"TYCHO: Supporting Permanently Crewed Lunar Exploration with High-Speed Optical Communication from Everywhere"
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As television became the main market, its demand for simultaneous delivery of relatively few signals of large
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The first and historically most important application for communication satellites was in intercontinental
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The Atlas-B with SCORE on the launch pad; the rocket (without booster engines) constituted the satellite.
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Some manufacturers have also introduced special antennas for mobile reception of DBS television. Using
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service has also recently used FSS technology as well for their programming packages requiring their
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become successful, because these channels distributed their programming to all of the local cable TV
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1874:, a subsidiary of JetBlue), which passengers can view on-board on LCD screens mounted in the seats.
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After the launches of the Telstar through Westar 1 satellites, RCA Americom (later GE Americom, now
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are also proposed for communication satellites covering the Moon alike communication satellites in
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of 86.4° and inter-satellite links provide service availability over the entire surface of Earth.
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2447:. Vol. 51, no. 10. Arthur C. Clarke Institute for Space Education. pp. 305–308.
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After the 1990s, satellite communication technology has been used as a means to connect to the
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program. This program was also unique at the time for its use of what then became known as the
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antenna, due to Dish Network needing more capacity to carry local television stations per the
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3081:"SKYTRAC #SatcomSeries: The Differences, Strengths, and Weaknesses of LEO and GEO Satellites"
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are used to further specify orbital details. MEO and LEO are non-geostationary orbit (NGSO).
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Another passive relay experiment primarily intended for military communications purposes was
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Satellite communications are still used in many applications today. Remote islands such as
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caused some decline in the use of satellites for fixed telephony in the late 20th century.
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Region 1: Europe, Africa, the Middle East, what was formerly the Soviet Union, and Mongolia
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When Intelsat was launched, the United States was the only launch source outside of the
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supporting different missions on surface and other orbits are considered, such as the
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satellites over North America provide a quite large amount of FTA channels on their K
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On 30 May 1974, the first geostationary communications satellite in the world to be
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3777:
2199:
2076:
2005:
1926:
1734:
1593:
1589:
1578:
1293:
has zero elevation and a satellite directly overhead has elevation of 90 degrees.)
1091:
804:
800:
in the United States, which, ironically, was then bought by its archrival in 2005.
573:
276:
2639:"United States Aeronautics and Space Activities - first Annual Report to Congress"
1480:(ITU). To facilitate frequency planning, the world is divided into three regions:
1136:
On 9 November 1972, Canada's first geostationary satellite serving the continent,
1053:
In 2013, the first four of a constellation of 20 MEO satellites was launched. The
3492:
Beyond Sputnik and the Space Race: The Origins of Global Satellite Communications
2406:"Military Satellite Communications Fundamentals | The Aerospace Corporation"
760:, launched on 26 July 1963. Syncom 2 was the first communications satellite in a
6002:
5868:
5558:
5541:
5413:
5253:
4903:
4813:
4798:
4758:
4718:
4577:
4202:
3863:
3797:
3413:
2092:
2080:
1784:
1727:
1703:
1638:
comsats. Two satellite types are used for North American television and radio:
1541:
1365:
1337:
1010:
communications satellite. Another system using this store and forward method is
723:(Post Office) to develop satellite communications, it was launched by NASA from
720:
592:
519:
452:
201:
118:
53:
30:
2436:"Extra-terrestrial Relays: Can Rocket Stations Give World-wide Radio Coverage?"
1490:
Region 3: Asia (excluding region 1 areas), Australia, and the southwest Pacific
6136:
6044:
5987:
5947:
5741:
5442:
5258:
4965:
4663:
4572:
4528:
4498:
4476:
4466:
4441:
4104:
3828:
3525:
3305:
3228:
2068:
1839:
1715:
1601:
1449:
1329:
1126:
979:
906:(LEO), and is about 160 to 2,000 kilometres (99 to 1,243 mi) above Earth.
669:
539:
published an article titled "Extraterrestrial Relays" in the British magazine
507:
464:
288:
252:
178:
85:
2521:
1706:
satellite TV channels are also usually distributed on FSS satellites in the K
630:
Work that was begun in the field of electrical intelligence gathering at the
6146:
5997:
5714:
5595:
5516:
5499:
5243:
4708:
4523:
4217:
4125:
4070:
3782:
3055:
2088:
1993:
1953:
1889:
1824:
1741:
1651:
1605:
1566:
1423:
Communications Satellites are usually composed of the following subsystems:
897:
range from 2,000 to 36,000 kilometres (1,200 to 22,400 mi) above Earth.
712:
692:
597:
569:
565:
550:
546:
516:
468:
283:
196:
3533:
2795:
2766:
2692:
2638:
2579:
1448:
Power subsystem, used to power the Satellite systems, normally composed of
1407:
cover the Earth. Also, dedicated communication satellites in orbits around
1285:(caused by signals reflecting off the ground and into the ground antenna).
771:
A direct extension of the passive experiments of Project West Ford was the
668:
The direct successor to SCORE was another ARPA-led project called Courier.
3467:
Manual on sea level measurement and interpretation, volume V: Radar gauges
942:
satellites are needed if the mission requires uninterrupted connectivity.
5238:
5228:
5145:
4970:
4793:
4084:
3883:
3848:
3843:
3833:
3823:
3818:
3694:
2159:
2104:
1984:. Examples of military systems that use communication satellites are the
1949:
1819:(Television Receive Only) receivers and dishes. It was also used in its K
1655:
1317:
1259:
1239:
1179:
1175:
1145:
1118:
1007:
987:
797:
480:
476:
556:
5233:
5218:
3888:
3873:
3792:
3772:
3741:
3731:
2061:
2045:
2025:
1985:
1831:
1788:
1776:
1764:
1673:
1659:
1384:
1333:
1325:
1321:
1263:
1137:
1105:
1011:
704:
653:
The first satellite purpose-built to actively relay communications was
488:
60:
5960:
5824:
5263:
5223:
4545:
4337:
4290:
3944:
3893:
3787:
3736:
3721:
3644:
3634:
2037:
2009:
1871:
1634:
to many receivers being a more precise match for the capabilities of
1341:
1313:
1309:
995:
867:
Communications satellites usually have one of three primary types of
793:
765:
757:
746:
680:
3408:. Berlin, Heidelberg: Springer Berlin Heidelberg. pp. 311–328.
2646:
Published as House Document Number 71, 86th Congress, first Session
1304:
series was launched on 23 April 1965 and was used for experimental
1076:
775:
program, also conducted by the Lincoln Laboratory on behalf of the
5248:
5185:
4493:
3929:
3726:
3404:
Kramer, Herbert J. (2002). "Data Collection (Messaging) Systems".
3380:"India's first 'military' satellite GSAT-7 put into earth's orbit"
2739:
Martin, Donald; Anderson, Paul; Bartamian, Lucy (March 16, 2007).
2611:
Martin, Donald; Anderson, Paul; Bartamian, Lucy (March 16, 2007).
1719:
1540:
1160:
1075:
868:
860:
780:
644:
589:
555:
545:. The article described the fundamentals behind the deployment of
472:
460:
440:
29:
1830:
Some satellites have been launched that have transponders in the
1810:
for each of the transponders' RF input and output (as opposed to
1250:(owns the former RCA Astro Electronics/GE Astro Space business),
1178:
in 1975. It was Satcom 1 that was instrumental in helping early
5190:
3746:
2585:
2229:
Orbital periods and speeds are calculated using the relations 4Ď€
2100:
2008:. India has launched its first Military Communication satellite
1997:
1989:
1931:
1847:
1816:
1796:
1749:
1408:
1164:
974:
and low-speed data services, primarily to remote areas, are the
752:
An immediate antecedent of the geostationary satellites was the
727:
on 10 July 1962, in the first privately sponsored space launch.
676:
5386:
4294:
4043:
3537:
5841:
5382:
4436:
4233:
3229:"TYCHO mission to Earth-Moon libration point EML-4 @ IAC 2013"
2013:
1918:
1215:
1211:
1187:
1054:
3527:
Beyond The Ionosphere: Fifty Years of Satellite Communication
3057:
Beyond The Ionosphere: Fifty Years of Satellite Communication
2797:
Beyond The Ionosphere: Fifty Years of Satellite Communication
2581:
Beyond The Ionosphere: Fifty Years of Satellite Communication
1748:'s "must-carry" regulations, and for more bandwidth to carry
4039:
1806:
band, and 12 feet (3.6 m) or larger for C band). They use
1399:
Other orbits are also planned to be used. Positions in the
1144:, with the United States following suit with the launch of
1104:
In applications that require many ground antennas, such as
1759:
is a communications satellite that transmits to small DBS
1387:
as a data network aiming to provide a „Lunar Internet for
608:
There are two major classes of communications satellites,
2032:
bands. Typically military satellites operate in the UHF,
1438:
Engines used to bring the satellite to its desired orbit
711:
as part of a multi-national agreement between AT&T,
2549:"Design of the first artificial satellite of the Earth"
966:
A group of satellites working in concert is known as a
3008:"NASA Compendium Of Satellite Communications Programs"
2933:"NASA Compendium Of Satellite Communications Programs"
2842:"NASA Compendium Of Satellite Communications Programs"
2698:. The White House. 18 January 1961. pp. 12–13, 26
1956:
connection, or require high availability of services.
2767:"United States Aeronautics and Space Activities 1962"
2693:"United States Aeronautics and Space Activities 1960"
1850:
have also launched experimental satellites carrying K
1616:
connected to the Public Switched Telephone Network .
1340:. In November 1967 Soviet engineers created a unique
982:
systems. The Iridium system has 66 satellites, which
483:
applications. Many communications satellites are in
2000:
satellites, United Kingdom satellites (for instance
1443:
station keeping tracking and stabilization subsystem
6155:
6108:
6060:
5946:
5882:
5787:
5707:
5698:
5586:
5420:
5272:
5209:
5131:
5095:
5052:
4993:
4927:
4636:
4328:
4226:
4195:
4134:
4113:
4077:
3984:
3963:
3912:
3806:
3760:
3708:
3627:
3571:
3507:
2772:. The White House. 28 January 1963. pp. 20, 96
1866:owners. Such mobile DBS antennas are also used by
792:In the United States, 1962 saw the creation of the
3328:"Indian GSLV successfully lofts GSAT-14 satellite"
2648:. The White House. 2 February 1959. pp. 13–14
2296:Approximately 8.6 times when the Moon is nearest
2115:). The data rate is typically much lower than in
1779:, DISH Network and Orby TV in the United States,
900:The region below medium orbits is referred to as
6246:Telecommunications-related introductions in 1962
2400:
2398:
1487:Region 2: North and South America and Greenland
970:. Two such constellations, intended to provide
2095:. It may be based on a secondary payload of a
1226:By 2000, Hughes Space and Communications (now
604:Early active and passive satellite experiments
27:Artificial satellite that relays radio signals
5398:
4306:
4055:
3971:Consultative Committee for Space Data Systems
3549:
3013:. NASA. December 1975. pp. 10-1 to 10-64
2267:is the gravitational constant, approximately
412:
8:
3464:. "Equipment needed for Telemetry of Data".
3406:Observation of the Earth and Its Environment
1427:Communication Payload, normally composed of
683:on 12 August 1960. Echo 1 was an aluminized
510:used for telecommunications links travel by
5321:Global telecommunications regulation bodies
3438:"Satellite Data Telecommunication Handbook"
2938:. NASA. December 1975. pp. 9-1 to 9-56
2847:. NASA. December 1975. pp. 5-1 to 5-16
1771:. DBS technology is used for DTH-oriented (
1452:, and batteries that maintain power during
788:International commercial satellite projects
5704:
5405:
5391:
5383:
5357:
4313:
4299:
4291:
4062:
4048:
4040:
3556:
3542:
3534:
3462:Intergovernmental Oceanographic Commission
1472:Frequency allocation for satellite systems
1468:can be used to arrive at the exact value.
588:. Sputnik 1 was equipped with an on-board
419:
405:
217:
183:
40:
3997:List of communication satellite companies
3102:"IADC Space Debris Mitigation Guidelines"
2687:
2685:
2316:, to 9.6 times when the Moon is farthest
2150:List of communication satellite companies
1159:was launched: the experimental satellite
463:. Communications satellites are used for
3494:(Johns Hopkins University Press, 2022);
2957:
2955:
2953:
2789:
2787:
2614:Communications Satellites: Project SCORE
2279:is the mass of Earth, approximately 5.98
2145:Inter-satellite communications satellite
1795:in the UK, Ireland, and New Zealand and
1356:, that was based on Molniya satellites.
826:
487:22,236 miles (35,785 km) above the
5890:Effect of spaceflight on the human body
3992:List of communications satellite firsts
3513:Communications satellites short history
2382:"Satellites - Communication Satellites"
2348:
2222:
2155:List of communications satellite firsts
1976:Communications satellites are used for
1921:radio equipment and highly directional
1046:In 1962, the communications satellite,
632:United States Naval Research Laboratory
576:on 4 October 1957. It was developed by
52:
5912:Psychological and sociological effects
3874:Shanghai Spacecom Satellite Technology
3124:The Basics of Satellite Communications
2559:from the original on 26 September 2023
2111:) or in dedicated satellites (such as
1650:satellites. Examples of these are the
1117:The first geostationary satellite was
893:(MEO) satellites are closer to Earth.
3360:from the original on 20 December 2023
2600:from the original on 29 October 2023.
2528:from the original on 24 November 2023
2454:from the original on 19 November 2023
1478:International Telecommunication Union
736:Massachusetts Institute of Technology
7:
5367:
4022:
1505:Broadcasting satellite service (BSS)
794:Communications Satellite Corporation
1228:Boeing Satellite Development Center
833:medium altitude orbits around Earth
777:United States Department of Defense
700:More firsts and further experiments
5621:Weather and environment monitoring
2964:Handbook of Satellite Applications
2742:Communications Satellites: Telstar
2487:from the original on 13 April 2023
2434:Clarke, Arthur C. (October 1945).
2259:is the orbital period in seconds;
2255:is the radius of orbit in metres;
2083:), may use satellites for one-way
1982:Global Command and Control Systems
1435:, amplifiers and switching systems
1391:spacecraft and Installations. The
1244:Indian Space Research Organisation
572:, which was put into orbit by the
25:
3655:Automatic Tracking Satellite Dish
1966:Military communications satellite
1775:) satellite TV services, such as
1559:Public Switched Telephone Network
1515:Radionavigation-satellite service
659:Advanced Research Projects Agency
6204:
6194:
6193:
5366:
5356:
5347:
5346:
5335:
4956:Free-space optical communication
4275:
4265:
4021:
4010:
4009:
2004:), and satellites of the former
1672:, and the lower portions of the
1520:Meteorological-satellite service
992:satellite internet constellation
879:Geostationary satellites have a
443:telecommunication signals via a
388:
5665:Space launch market competition
3127:. Intl. Engineering Consortiu.
3079:Mann, Reuben (April 26, 2022).
2506:Siddiqi, Asif (November 2007).
2356:Labrador, Virgil (2015-02-19).
1859:Global Positioning System (GPS)
1575:submarine communications cables
1413:Mars Telecommunications Orbiter
634:in 1951 led to a project named
18:Active communications satellite
6251:Wireless communication systems
5902:Health threat from cosmic rays
3508:Satellite Industry Association
3227:Hornig, Andreas (2013-10-06).
3208:Hornig, Andreas (2022-05-01).
3149:"Soyuz Flight VS05 Launch Kit"
2135:High-altitude platform station
2012:, its transponders operate in
1972:X Band Satellite Communication
1823:band form for the now-defunct
831:Clickable image, highlighting
773:Lincoln Experimental Satellite
1:
2473:Mills, Mike (3 August 1997).
2263:is the orbital speed in m/s;
1888:Satellite radio offers audio
1692:by schools and universities,
1688:), as well as being used for
1500:Fixed satellite service (FSS)
1324:and the Russian Far East, in
5342:Telecommunication portal
5123:Telecommunications equipment
4357:
4272:Telecommunication portal
3976:ETSI Satellite Digital Radio
3700:Very-small-aperture terminal
2508:"The Man Behind the Curtain"
2412:. 2010-04-01. Archived from
2140:History of telecommunication
1236:Orbital Sciences Corporation
6018:Self-replicating spacecraft
5854:International Space Station
4859:Alexander Stepanovich Popov
3752:Digital audio radio service
3660:Motor-driven Satellite dish
3414:10.1007/978-3-642-56294-5_4
3356:. SpaceRef. 26 April 2005.
2513:Air & Space/Smithsonian
1401:Earth-Moon-Libration points
1300:The first satellite of the
1182:channels such as WTBS (now
1059:broadband internet services
713:Bell Telephone Laboratories
361:List of space organizations
6267:
5532:Space Liability Convention
4563:Telecommunications history
3121:Pelton, Joseph N. (2006).
2130:Commercialization of space
1969:
1963:
1941:
1902:
1881:
1757:direct broadcast satellite
1640:Direct broadcast satellite
1623:
1534:
1379:Beyond geostationary orbit
1363:
1273:
1125:. Shortly after Syncom 3,
1069:
1021:
959:
918:
618:. Passive satellites only
566:artificial Earth satellite
459:at different locations on
439:that relays and amplifies
6231:Communications satellites
6188:
5895:Space adaptation syndrome
5330:
5171:Public Switched Telephone
4983:telecommunication circuit
4944:Fiber-optic communication
4689:Francis Blake (telephone)
4484:Optical telecommunication
4262:
4147:Communications satellites
4005:
3807:Relay satellite companies
3604:High-throughput satellite
3589:Satellite Internet access
3276:"Orby TV (United States)"
2384:. Satellites.spacesim.org
2358:"satellite communication"
1944:Satellite Internet access
1870:for DirecTV (supplied by
1066:Geostationary orbit (GEO)
1000:satellite Internet access
857:Van Allen radiation belts
5628:Communications satellite
5082:Orbital angular-momentum
4519:Satellite communications
4358:Communications satellite
3565:Satellite communications
2165:Reconnaissance satellite
2065:environmental monitoring
1666:Fixed Service Satellites
1510:Mobile-satellite service
1018:Medium Earth orbit (MEO)
636:Communication Moon Relay
497:satellite constellations
433:communications satellite
6132:reusable launch systems
5749:Extravehicular activity
5660:Commercial use of space
5564:Militarisation of space
5537:Registration Convention
5453:Accidents and incidents
4961:Molecular communication
4784:Gardiner Greene Hubbard
4613:Undersea telegraph line
4348:Cable protection system
4142:Cable protection system
3913:Satellite manufacturers
3060:. NASA History Office.
2800:. NASA History Office.
2195:Satellite space segment
1978:military communications
1905:Amateur radio satellite
1854:band beacons recently.
1644:Fixed Service Satellite
1555:long distance telephony
998:, that aims for global
968:satellite constellation
962:Satellite constellation
956:Satellite constellation
873:orbital classifications
853:Moon's orbital distance
817:highly elliptical orbit
754:Hughes Aircraft Company
91:Timeline of spaceflight
6236:Satellite broadcasting
6180:Mission control center
6142:Non-rocket spacelaunch
5576:Billionaire space race
5103:Communication protocol
4889:Charles Sumner Tainter
4704:Walter Houser Brattain
4649:Edwin Howard Armstrong
4457:Information revolution
3304:. ISRO. Archived from
2966:. New York: Springer.
2745:(5th ed.). AIAA.
2617:(5th ed.). AIAA.
2170:Relay (disambiguation)
1996:of the United States,
1980:applications, such as
1934:or similar protocols.
1827:satellite TV service.
1550:
1283:multipath interference
1083:
864:
851:, at one ninth of the
650:
586:Konstantin Tsiolkovsky
584:, building on work by
561:
395:Spaceflight portal
311:Non-rocket spacelaunch
81:History of spaceflight
65:
38:
6030:Spacecraft propulsion
5480:European Space Agency
5077:Polarization-division
4809:Narinder Singh Kapany
4774:Erna Schneider Hoover
4694:Jagadish Chandra Bose
4674:Alexander Graham Bell
4405:online video platform
4282:Telephones portal
2547:Zak, Anatoly (2017).
1970:Further information:
1812:circular polarization
1544:
1254:, Alcatel Space, now
1157:three-axis stabilized
1079:
915:Low Earth orbit (LEO)
830:
648:
559:
547:artificial satellites
449:communication channel
64:
33:
5655:Satellite navigation
4919:Vladimir K. Zworykin
4879:Almon Brown Strowger
4849:Charles Grafton Page
4504:Prepaid mobile phone
4432:Electrical telegraph
4244:Telephone newspapers
3579:Satellite television
3529:(NASA SP-4217, 1997)
3247:"Connected:Maritime"
1864:recreational vehicle
1838:, such as DirecTV's
1626:Satellite television
1405:geosynchronous orbit
1393:Moonlight Initiative
1350:satellite television
1320:stations located in
1123:1964 Summer Olympics
1090:(one revolution per
815:, which describes a
762:geosynchronous orbit
715:, NASA, the British
687:acting as a passive
673:from the satellite.
663:Dwight D. Eisenhower
625:free-space path loss
560:Replica of Sputnik 1
437:artificial satellite
6040:Electric propulsion
5727:Life-support system
5611:Imagery and mapping
5571:Private spaceflight
4869:Johann Philipp Reis
4628:Wireless revolution
4590:The Telephone Cases
4447:Hydraulic telegraph
4167:Mobile phone signal
3964:Trade organizations
3955:Thales Alenia Space
3768:Astra Digital Radio
3761:Broadcast companies
3690:Satellite data unit
3192:"Moonlight Webinar"
3178:"Project Moonlight"
3066:1997bify.book.....B
2972:2017hsa..book.....P
2820:"Project West Ford"
2806:1997bify.book.....B
2594:1997bify.book.....B
2553:RussianSpaceWeb.com
2480:The Washington Post
2205:Traveling-wave tube
2180:Satellite data unit
2099:(as in the case of
2067:equipment (such as
2052:) frequency bands.
1808:linear polarization
1712:Intelsat Americas 5
1694:business television
1577:through the use of
1256:Thales Alenia Space
1232:Space Systems/Loral
1200:The Weather Channel
1081:Geostationary orbit
1072:Geostationary orbit
1057:satellites provide
984:orbital inclination
882:geostationary orbit
845:geostationary orbit
734:, which was led by
721:French National PTT
717:General Post Office
578:Mikhail Tikhonravov
485:geostationary orbit
233:Apollo Lunar Module
6241:Satellites by type
5993:Robotic spacecraft
5919:Space and survival
5774:Space colonization
5670:Space architecture
5522:Outer Space Treaty
5067:Frequency-division
5044:Telephone exchange
4914:Charles Wheatstone
4844:Jun-ichi Nishizawa
4819:Innocenzo Manzetti
4754:Reginald Fessenden
4489:Optical telegraphy
4322:Telecommunications
4157:Free-space optical
3783:Sirius XM Holdings
3674:Parabolic antennas
3522:by David J. Whalen
3518:2015-05-12 at the
2175:Satcom On The Move
2117:satellite Internet
2107:and others in the
1878:Radio broadcasting
1551:
1140:, was launched by
1084:
1024:Medium Earth orbit
890:Medium Earth orbit
865:
740:Lincoln Laboratory
651:
623:attenuated due to
562:
190:Robotic spacecraft
66:
39:
6218:
6217:
6165:Flight controller
5942:
5941:
5700:Human spaceflight
5675:Space exploration
5601:Earth observation
5380:
5379:
5118:Store and forward
5113:Data transmission
5027:Network switching
4978:Transmission line
4824:Guglielmo Marconi
4789:Internet pioneers
4654:Mohamed M. Atalla
4623:Whistled language
4288:
4287:
4121:Answering machine
4037:
4036:
3594:Amateur satellite
3490:Slotten, Hugh R.
3423:978-3-642-62688-3
3332:NASA Space Flight
3308:on 8 January 2014
3134:978-1-931695-48-0
2283:10 kg (1.318
2097:weather satellite
2085:data transmission
1799:in South Africa.
1781:Bell Satellite TV
1698:Videoconferencing
1690:distance learning
1569:telephones to an
1466:network simulator
1152:on 13 April 1974.
895:Orbital altitudes
732:Project West Ford
685:balloon satellite
535:In October 1945,
451:between a source
429:
428:
323:Spaceflight types
267:
266:
224:Crewed spacecraft
216:
215:
131:Earth observation
36:Iridium satellite
16:(Redirected from
6258:
6208:
6197:
6196:
5907:Space psychology
5732:Animals in space
5705:
5685:Space technology
5527:Rescue Agreement
5407:
5400:
5393:
5384:
5370:
5369:
5360:
5359:
5350:
5349:
5340:
5339:
5338:
5211:Notable networks
5201:Wireless network
5141:Cellular network
5133:Types of network
5108:Computer network
4995:Network topology
4909:Thomas A. Watson
4764:Oliver Heaviside
4749:Philo Farnsworth
4724:Daniel Davis Jr.
4699:Charles Bourseul
4659:John Logie Baird
4368:Data compression
4363:Computer network
4315:
4308:
4301:
4292:
4280:
4279:
4278:
4270:
4269:
4268:
4234:Fax transmission
4182:Submarine cables
4064:
4057:
4050:
4041:
4025:
4024:
4013:
4012:
3940:Northrop Grumman
3619:Carriage dispute
3558:
3551:
3544:
3535:
3478:
3477:
3475:
3474:
3458:
3452:
3451:
3449:
3448:
3434:
3428:
3427:
3401:
3395:
3394:
3392:
3391:
3376:
3370:
3369:
3367:
3365:
3350:
3344:
3343:
3341:
3339:
3334:. 4 January 2014
3324:
3318:
3317:
3315:
3313:
3298:
3292:
3291:
3289:
3287:
3278:. Archived from
3272:
3266:
3265:
3263:
3262:
3253:. Archived from
3243:
3237:
3236:
3224:
3218:
3217:
3205:
3199:
3198:
3196:
3188:
3182:
3181:
3174:
3168:
3167:
3165:
3163:
3153:
3145:
3139:
3138:
3118:
3112:
3111:
3106:
3098:
3092:
3091:
3089:
3087:
3076:
3070:
3069:
3051:
3045:
3044:
3042:
3040:
3029:
3023:
3022:
3020:
3018:
3012:
3004:
2998:
2997:
2995:
2993:
2982:
2976:
2975:
2959:
2948:
2947:
2945:
2943:
2937:
2929:
2923:
2922:
2920:
2918:
2907:
2901:
2900:
2898:
2896:
2885:
2879:
2878:
2876:
2874:
2863:
2857:
2856:
2854:
2852:
2846:
2838:
2832:
2831:
2829:
2827:
2816:
2810:
2809:
2791:
2782:
2781:
2779:
2777:
2771:
2763:
2757:
2756:
2736:
2730:
2729:
2727:
2725:
2714:
2708:
2707:
2705:
2703:
2697:
2689:
2680:
2679:
2677:
2675:
2664:
2658:
2657:
2655:
2653:
2643:
2635:
2629:
2628:
2608:
2602:
2601:
2588:History Office.
2575:
2569:
2568:
2566:
2564:
2544:
2538:
2537:
2535:
2533:
2503:
2497:
2496:
2494:
2492:
2470:
2464:
2463:
2461:
2459:
2453:
2440:
2431:
2425:
2424:
2422:
2421:
2402:
2393:
2392:
2390:
2389:
2378:
2372:
2371:
2369:
2368:
2353:
2336:
2335:
2333:
2331:
2330:
2327:
2324:
2315:
2313:
2311:
2310:
2307:
2304:
2294:
2288:
2286:
2282:
2274:
2272:
2227:
2073:weather stations
1761:satellite dishes
1586:Ascension Island
1252:Northrop Grumman
1096:equatorial orbit
1088:angular velocity
927:
841:High Earth orbit
823:Satellite orbits
640:Washington, D.C.
537:Arthur C. Clarke
421:
414:
407:
393:
392:
391:
218:
207:Cargo spacecraft
184:
41:
21:
6266:
6265:
6261:
6260:
6259:
6257:
6256:
6255:
6221:
6220:
6219:
6214:
6184:
6151:
6123:Escape velocity
6104:
6056:
6023:Space telescope
5976:Reentry capsule
5938:
5878:
5783:
5754:Overview effect
5737:Bioastronautics
5694:
5582:
5416:
5411:
5381:
5376:
5336:
5334:
5326:
5268:
5205:
5127:
5091:
5048:
4997:
4989:
4930:
4923:
4829:Robert Metcalfe
4684:Tim Berners-Lee
4632:
4452:Information Age
4324:
4319:
4289:
4284:
4276:
4274:
4266:
4264:
4258:
4239:Telephone calls
4222:
4191:
4130:
4109:
4100:Satellite phone
4090:Cable telephony
4073:
4068:
4038:
4033:
4001:
3980:
3959:
3935:Lockheed Martin
3908:
3814:AST SpaceMobile
3802:
3756:
3710:Satellite radio
3704:
3685:Satellite modem
3680:Satellite phone
3665:Multi-satellite
3623:
3609:Relay satellite
3584:Satellite radio
3567:
3562:
3520:Wayback Machine
3504:
3487:
3485:Further reading
3482:
3481:
3472:
3470:
3460:
3459:
3455:
3446:
3444:
3442:library.wmo.int
3436:
3435:
3431:
3424:
3403:
3402:
3398:
3389:
3387:
3378:
3377:
3373:
3363:
3361:
3352:
3351:
3347:
3337:
3335:
3326:
3325:
3321:
3311:
3309:
3300:
3299:
3295:
3285:
3283:
3282:on 28 July 2020
3274:
3273:
3269:
3260:
3258:
3245:
3244:
3240:
3226:
3225:
3221:
3207:
3206:
3202:
3194:
3190:
3189:
3185:
3176:
3175:
3171:
3161:
3159:
3151:
3147:
3146:
3142:
3135:
3120:
3119:
3115:
3104:
3100:
3099:
3095:
3085:
3083:
3078:
3077:
3073:
3053:
3052:
3048:
3038:
3036:
3031:
3030:
3026:
3016:
3014:
3010:
3006:
3005:
3001:
2991:
2989:
2984:
2983:
2979:
2961:
2960:
2951:
2941:
2939:
2935:
2931:
2930:
2926:
2916:
2914:
2909:
2908:
2904:
2894:
2892:
2887:
2886:
2882:
2872:
2870:
2865:
2864:
2860:
2850:
2848:
2844:
2840:
2839:
2835:
2825:
2823:
2818:
2817:
2813:
2793:
2792:
2785:
2775:
2773:
2769:
2765:
2764:
2760:
2753:
2738:
2737:
2733:
2723:
2721:
2716:
2715:
2711:
2701:
2699:
2695:
2691:
2690:
2683:
2673:
2671:
2666:
2665:
2661:
2651:
2649:
2641:
2637:
2636:
2632:
2625:
2610:
2609:
2605:
2577:
2576:
2572:
2562:
2560:
2546:
2545:
2541:
2531:
2529:
2505:
2504:
2500:
2490:
2488:
2472:
2471:
2467:
2457:
2455:
2451:
2438:
2433:
2432:
2428:
2419:
2417:
2404:
2403:
2396:
2387:
2385:
2380:
2379:
2375:
2366:
2364:
2355:
2354:
2350:
2345:
2340:
2339:
2328:
2325:
2323:405,696 km
2322:
2321:
2319:
2317:
2308:
2305:
2303:363,104 km
2302:
2301:
2299:
2297:
2295:
2291:
2284:
2280:
2270:
2268:
2228:
2224:
2219:
2214:
2209:
2200:Space pollution
2190:Satellite modem
2185:Satellite delay
2125:
2058:
2056:Data collection
2049:
2044:(also known as
2036:(also known as
2029:
1974:
1968:
1962:
1946:
1940:
1938:Internet access
1907:
1901:
1886:
1884:Satellite radio
1880:
1868:JetBlue Airways
1853:
1842:satellite, and
1835:
1822:
1805:
1768:
1725:
1709:
1677:
1628:
1622:
1563:telephone calls
1539:
1537:Satellite phone
1533:
1528:
1474:
1421:
1381:
1368:
1362:
1344:of national TV
1278:
1272:
1248:Lockheed Martin
1114:
1112:Examples of GEO
1074:
1068:
1043:
1041:Examples of MEO
1026:
1020:
972:satellite phone
964:
958:
947:signal strength
936:low Earth orbit
932:
930:Low Earth orbit
925:
923:
921:Low Earth orbit
917:
903:low Earth orbit
849:graveyard orbit
825:
790:
702:
606:
533:
528:
501:low Earth orbit
447:; it creates a
425:
389:
387:
382:
381:
362:
354:
353:
324:
316:
315:
306:Escape velocity
301:launch vehicles
279:
269:
268:
263:
262:
226:
212:
211:
192:
181:
171:
170:
121:
111:
110:
76:
28:
23:
22:
15:
12:
11:
5:
6264:
6262:
6254:
6253:
6248:
6243:
6238:
6233:
6223:
6222:
6216:
6215:
6213:
6212:
6201:
6189:
6186:
6185:
6183:
6182:
6177:
6172:
6170:Ground station
6167:
6161:
6159:
6157:Ground segment
6153:
6152:
6150:
6149:
6144:
6139:
6134:
6125:
6120:
6114:
6112:
6106:
6105:
6103:
6102:
6097:
6092:
6090:Interplanetary
6087:
6086:
6085:
6083:Geosynchronous
6080:
6070:
6064:
6062:
6058:
6057:
6055:
6054:
6053:
6052:
6050:Gravity assist
6047:
6042:
6037:
6027:
6026:
6025:
6020:
6015:
6010:
6005:
6000:
5990:
5985:
5984:
5983:
5981:Service module
5978:
5973:
5971:Orbital module
5963:
5958:
5956:Launch vehicle
5952:
5950:
5944:
5943:
5940:
5939:
5937:
5936:
5934:Space sexology
5931:
5926:
5924:Space medicine
5921:
5916:
5915:
5914:
5904:
5899:
5898:
5897:
5886:
5884:
5880:
5879:
5877:
5876:
5871:
5866:
5861:
5856:
5851:
5850:
5849:
5839:
5834:
5833:
5832:
5827:
5817:
5812:
5807:
5802:
5797:
5791:
5789:
5785:
5784:
5782:
5781:
5776:
5771:
5766:
5761:
5759:Weightlessness
5756:
5751:
5746:
5745:
5744:
5739:
5734:
5724:
5723:
5722:
5711:
5709:
5702:
5696:
5695:
5693:
5692:
5687:
5682:
5680:Space research
5677:
5672:
5667:
5662:
5657:
5652:
5651:
5650:
5645:
5640:
5635:
5625:
5624:
5623:
5618:
5616:Reconnaissance
5613:
5608:
5598:
5592:
5590:
5584:
5583:
5581:
5580:
5579:
5578:
5568:
5567:
5566:
5561:
5556:
5546:
5545:
5544:
5539:
5534:
5529:
5524:
5514:
5513:
5512:
5507:
5502:
5497:
5492:
5487:
5485:European Union
5482:
5477:
5472:
5462:
5457:
5456:
5455:
5450:
5445:
5440:
5430:
5424:
5422:
5418:
5417:
5412:
5410:
5409:
5402:
5395:
5387:
5378:
5377:
5375:
5374:
5364:
5354:
5344:
5331:
5328:
5327:
5325:
5324:
5317:
5312:
5307:
5302:
5297:
5296:
5295:
5290:
5282:
5276:
5274:
5270:
5269:
5267:
5266:
5261:
5256:
5251:
5246:
5241:
5236:
5231:
5226:
5221:
5215:
5213:
5207:
5206:
5204:
5203:
5198:
5193:
5188:
5183:
5178:
5173:
5168:
5163:
5158:
5153:
5148:
5143:
5137:
5135:
5129:
5128:
5126:
5125:
5120:
5115:
5110:
5105:
5099:
5097:
5093:
5092:
5090:
5089:
5084:
5079:
5074:
5069:
5064:
5062:Space-division
5058:
5056:
5050:
5049:
5047:
5046:
5041:
5040:
5039:
5034:
5024:
5023:
5022:
5012:
5007:
5001:
4999:
4991:
4990:
4988:
4987:
4986:
4985:
4975:
4974:
4973:
4963:
4958:
4953:
4952:
4951:
4941:
4935:
4933:
4925:
4924:
4922:
4921:
4916:
4911:
4906:
4901:
4899:Camille Tissot
4896:
4891:
4886:
4881:
4876:
4874:Claude Shannon
4871:
4866:
4864:Tivadar Puskás
4861:
4856:
4851:
4846:
4841:
4836:
4834:Antonio Meucci
4831:
4826:
4821:
4816:
4811:
4806:
4804:Charles K. Kao
4801:
4796:
4791:
4786:
4781:
4779:Harold Hopkins
4776:
4771:
4766:
4761:
4756:
4751:
4746:
4741:
4736:
4731:
4726:
4721:
4716:
4711:
4706:
4701:
4696:
4691:
4686:
4681:
4679:Emile Berliner
4676:
4671:
4666:
4661:
4656:
4651:
4646:
4640:
4638:
4634:
4633:
4631:
4630:
4625:
4620:
4618:Videotelephony
4615:
4610:
4609:
4608:
4603:
4593:
4586:
4581:
4575:
4570:
4565:
4560:
4555:
4554:
4553:
4548:
4543:
4533:
4532:
4531:
4521:
4516:
4514:Radiotelephone
4511:
4506:
4501:
4496:
4491:
4486:
4481:
4480:
4479:
4469:
4464:
4459:
4454:
4449:
4444:
4439:
4434:
4429:
4424:
4419:
4418:
4417:
4412:
4407:
4402:
4400:Internet video
4392:
4391:
4390:
4385:
4380:
4375:
4365:
4360:
4355:
4350:
4345:
4340:
4334:
4332:
4326:
4325:
4320:
4318:
4317:
4310:
4303:
4295:
4286:
4285:
4263:
4260:
4259:
4257:
4256:
4251:
4246:
4241:
4236:
4230:
4228:
4224:
4223:
4221:
4220:
4215:
4210:
4208:Misdialed call
4205:
4199:
4197:
4193:
4192:
4190:
4189:
4184:
4179:
4174:
4169:
4164:
4159:
4154:
4149:
4144:
4138:
4136:
4132:
4131:
4129:
4128:
4123:
4117:
4115:
4111:
4110:
4108:
4107:
4102:
4097:
4092:
4087:
4081:
4079:
4075:
4074:
4069:
4067:
4066:
4059:
4052:
4044:
4035:
4034:
4032:
4031:
4019:
4006:
4003:
4002:
4000:
3999:
3994:
3988:
3986:
3982:
3981:
3979:
3978:
3973:
3967:
3965:
3961:
3960:
3958:
3957:
3952:
3947:
3942:
3937:
3932:
3927:
3922:
3916:
3914:
3910:
3909:
3907:
3906:
3901:
3896:
3891:
3886:
3881:
3876:
3871:
3866:
3861:
3856:
3851:
3846:
3841:
3836:
3831:
3826:
3821:
3816:
3810:
3808:
3804:
3803:
3801:
3800:
3795:
3790:
3785:
3780:
3775:
3770:
3764:
3762:
3758:
3757:
3755:
3754:
3749:
3744:
3739:
3734:
3729:
3724:
3718:
3716:
3706:
3705:
3703:
3702:
3697:
3692:
3687:
3682:
3677:
3670:Satellite dish
3667:
3662:
3657:
3652:
3647:
3642:
3637:
3631:
3629:
3625:
3624:
3622:
3621:
3616:
3611:
3606:
3601:
3599:Ground station
3596:
3591:
3586:
3581:
3575:
3573:
3569:
3568:
3563:
3561:
3560:
3553:
3546:
3538:
3532:
3531:
3523:
3510:
3503:
3502:External links
3500:
3499:
3498:
3486:
3483:
3480:
3479:
3453:
3429:
3422:
3396:
3371:
3345:
3319:
3293:
3267:
3238:
3219:
3200:
3183:
3169:
3158:. June 1, 2013
3140:
3133:
3113:
3093:
3071:
3046:
3024:
2999:
2977:
2949:
2924:
2902:
2880:
2858:
2833:
2811:
2783:
2758:
2752:978-1884989193
2751:
2731:
2709:
2681:
2659:
2630:
2624:978-1884989193
2623:
2603:
2570:
2539:
2498:
2465:
2444:Wireless World
2426:
2394:
2373:
2362:Britannica.com
2347:
2346:
2344:
2341:
2338:
2337:
2329:42,164 km
2309:42,164 km
2289:
2221:
2220:
2218:
2215:
2213:
2210:
2208:
2207:
2202:
2197:
2192:
2187:
2182:
2177:
2172:
2167:
2162:
2157:
2152:
2147:
2142:
2137:
2132:
2126:
2124:
2121:
2057:
2054:
2047:
2027:
1964:Main article:
1961:
1958:
1942:Main article:
1939:
1936:
1903:Main article:
1900:
1897:
1882:Main article:
1879:
1876:
1851:
1833:
1820:
1803:
1773:Direct-To-Home
1766:
1723:
1707:
1675:
1636:geosynchronous
1624:Main article:
1621:
1618:
1535:Main article:
1532:
1529:
1527:
1524:
1523:
1522:
1517:
1512:
1507:
1502:
1492:
1491:
1488:
1485:
1473:
1470:
1461:
1460:
1456:
1446:
1439:
1436:
1420:
1417:
1380:
1377:
1364:Main article:
1361:
1358:
1312:from a Moscow
1274:Main article:
1271:
1268:
1224:
1223:
1168:
1153:
1142:Telesat Canada
1134:
1113:
1110:
1070:Main article:
1067:
1064:
1063:
1062:
1051:
1042:
1039:
1022:Main article:
1019:
1016:
960:Main article:
957:
954:
924:
919:Main article:
916:
913:
908:
907:
898:
886:
871:, while other
839:to the lowest
824:
821:
789:
786:
725:Cape Canaveral
701:
698:
605:
602:
582:Sergey Korolev
542:Wireless World
532:
529:
527:
524:
493:satellite dish
427:
426:
424:
423:
416:
409:
401:
398:
397:
384:
383:
380:
379:
374:
369:
367:Space agencies
363:
360:
359:
356:
355:
352:
351:
346:
341:
339:Interplanetary
336:
331:
325:
322:
321:
318:
317:
314:
313:
308:
303:
291:
286:
280:
275:
274:
271:
270:
265:
264:
261:
260:
255:
250:
248:Space stations
245:
240:
238:Space capsules
235:
230:
227:
222:
221:
214:
213:
210:
209:
204:
199:
193:
188:
187:
182:
177:
176:
173:
172:
169:
168:
163:
158:
153:
148:
143:
138:
133:
128:
126:Communications
122:
117:
116:
113:
112:
109:
108:
103:
101:Lunar missions
98:
93:
88:
83:
77:
72:
71:
68:
67:
57:
56:
50:
49:
34:Replica of an
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
6263:
6252:
6249:
6247:
6244:
6242:
6239:
6237:
6234:
6232:
6229:
6228:
6226:
6211:
6207:
6202:
6200:
6191:
6190:
6187:
6181:
6178:
6176:
6173:
6171:
6168:
6166:
6163:
6162:
6160:
6158:
6154:
6148:
6145:
6143:
6140:
6138:
6135:
6133:
6129:
6126:
6124:
6121:
6119:
6118:Direct ascent
6116:
6115:
6113:
6111:
6107:
6101:
6100:Intergalactic
6098:
6096:
6093:
6091:
6088:
6084:
6081:
6079:
6076:
6075:
6074:
6071:
6069:
6066:
6065:
6063:
6059:
6051:
6048:
6046:
6043:
6041:
6038:
6036:
6035:Rocket engine
6033:
6032:
6031:
6028:
6024:
6021:
6019:
6016:
6014:
6011:
6009:
6006:
6004:
6001:
5999:
5996:
5995:
5994:
5991:
5989:
5986:
5982:
5979:
5977:
5974:
5972:
5969:
5968:
5967:
5966:Space capsule
5964:
5962:
5959:
5957:
5954:
5953:
5951:
5949:
5945:
5935:
5932:
5930:
5929:Space nursing
5927:
5925:
5922:
5920:
5917:
5913:
5910:
5909:
5908:
5905:
5903:
5900:
5896:
5893:
5892:
5891:
5888:
5887:
5885:
5883:Health issues
5881:
5875:
5872:
5870:
5867:
5865:
5862:
5860:
5857:
5855:
5852:
5848:
5845:
5844:
5843:
5840:
5838:
5837:Space Shuttle
5835:
5831:
5828:
5826:
5823:
5822:
5821:
5818:
5816:
5813:
5811:
5808:
5806:
5803:
5801:
5798:
5796:
5793:
5792:
5790:
5786:
5780:
5777:
5775:
5772:
5770:
5769:Space tourism
5767:
5765:
5762:
5760:
5757:
5755:
5752:
5750:
5747:
5743:
5740:
5738:
5735:
5733:
5730:
5729:
5728:
5725:
5721:
5718:
5717:
5716:
5713:
5712:
5710:
5706:
5703:
5701:
5697:
5691:
5690:Space weather
5688:
5686:
5683:
5681:
5678:
5676:
5673:
5671:
5668:
5666:
5663:
5661:
5658:
5656:
5653:
5649:
5646:
5644:
5641:
5639:
5636:
5634:
5631:
5630:
5629:
5626:
5622:
5619:
5617:
5614:
5612:
5609:
5607:
5604:
5603:
5602:
5599:
5597:
5594:
5593:
5591:
5589:
5585:
5577:
5574:
5573:
5572:
5569:
5565:
5562:
5560:
5557:
5555:
5554:Space command
5552:
5551:
5550:
5549:Space warfare
5547:
5543:
5540:
5538:
5535:
5533:
5530:
5528:
5525:
5523:
5520:
5519:
5518:
5515:
5511:
5510:United States
5508:
5506:
5503:
5501:
5498:
5496:
5493:
5491:
5488:
5486:
5483:
5481:
5478:
5476:
5473:
5471:
5468:
5467:
5466:
5463:
5461:
5458:
5454:
5451:
5449:
5446:
5444:
5441:
5439:
5436:
5435:
5434:
5431:
5429:
5428:Astrodynamics
5426:
5425:
5423:
5419:
5415:
5408:
5403:
5401:
5396:
5394:
5389:
5388:
5385:
5373:
5365:
5363:
5355:
5353:
5345:
5343:
5333:
5332:
5329:
5322:
5318:
5316:
5313:
5311:
5308:
5306:
5303:
5301:
5298:
5294:
5291:
5289:
5286:
5285:
5283:
5281:
5278:
5277:
5275:
5271:
5265:
5262:
5260:
5257:
5255:
5252:
5250:
5247:
5245:
5242:
5240:
5237:
5235:
5232:
5230:
5227:
5225:
5222:
5220:
5217:
5216:
5214:
5212:
5208:
5202:
5199:
5197:
5194:
5192:
5189:
5187:
5184:
5182:
5179:
5177:
5174:
5172:
5169:
5167:
5164:
5162:
5159:
5157:
5154:
5152:
5149:
5147:
5144:
5142:
5139:
5138:
5136:
5134:
5130:
5124:
5121:
5119:
5116:
5114:
5111:
5109:
5106:
5104:
5101:
5100:
5098:
5094:
5088:
5087:Code-division
5085:
5083:
5080:
5078:
5075:
5073:
5072:Time-division
5070:
5068:
5065:
5063:
5060:
5059:
5057:
5055:
5051:
5045:
5042:
5038:
5035:
5033:
5030:
5029:
5028:
5025:
5021:
5018:
5017:
5016:
5013:
5011:
5008:
5006:
5003:
5002:
5000:
4998:and switching
4996:
4992:
4984:
4981:
4980:
4979:
4976:
4972:
4969:
4968:
4967:
4964:
4962:
4959:
4957:
4954:
4950:
4949:optical fiber
4947:
4946:
4945:
4942:
4940:
4939:Coaxial cable
4937:
4936:
4934:
4932:
4926:
4920:
4917:
4915:
4912:
4910:
4907:
4905:
4902:
4900:
4897:
4895:
4892:
4890:
4887:
4885:
4882:
4880:
4877:
4875:
4872:
4870:
4867:
4865:
4862:
4860:
4857:
4855:
4854:Radia Perlman
4852:
4850:
4847:
4845:
4842:
4840:
4837:
4835:
4832:
4830:
4827:
4825:
4822:
4820:
4817:
4815:
4812:
4810:
4807:
4805:
4802:
4800:
4797:
4795:
4792:
4790:
4787:
4785:
4782:
4780:
4777:
4775:
4772:
4770:
4767:
4765:
4762:
4760:
4757:
4755:
4752:
4750:
4747:
4745:
4744:Lee de Forest
4742:
4740:
4739:Thomas Edison
4737:
4735:
4732:
4730:
4729:Donald Davies
4727:
4725:
4722:
4720:
4717:
4715:
4714:Claude Chappe
4712:
4710:
4707:
4705:
4702:
4700:
4697:
4695:
4692:
4690:
4687:
4685:
4682:
4680:
4677:
4675:
4672:
4670:
4667:
4665:
4662:
4660:
4657:
4655:
4652:
4650:
4647:
4645:
4642:
4641:
4639:
4635:
4629:
4626:
4624:
4621:
4619:
4616:
4614:
4611:
4607:
4604:
4602:
4599:
4598:
4597:
4594:
4592:
4591:
4587:
4585:
4582:
4579:
4576:
4574:
4571:
4569:
4566:
4564:
4561:
4559:
4558:Smoke signals
4556:
4552:
4549:
4547:
4544:
4542:
4539:
4538:
4537:
4536:Semiconductor
4534:
4530:
4527:
4526:
4525:
4522:
4520:
4517:
4515:
4512:
4510:
4507:
4505:
4502:
4500:
4497:
4495:
4492:
4490:
4487:
4485:
4482:
4478:
4475:
4474:
4473:
4470:
4468:
4465:
4463:
4460:
4458:
4455:
4453:
4450:
4448:
4445:
4443:
4440:
4438:
4435:
4433:
4430:
4428:
4425:
4423:
4420:
4416:
4413:
4411:
4408:
4406:
4403:
4401:
4398:
4397:
4396:
4395:Digital media
4393:
4389:
4386:
4384:
4381:
4379:
4376:
4374:
4371:
4370:
4369:
4366:
4364:
4361:
4359:
4356:
4354:
4351:
4349:
4346:
4344:
4341:
4339:
4336:
4335:
4333:
4331:
4327:
4323:
4316:
4311:
4309:
4304:
4302:
4297:
4296:
4293:
4283:
4273:
4261:
4255:
4252:
4250:
4247:
4245:
4242:
4240:
4237:
4235:
4232:
4231:
4229:
4225:
4219:
4216:
4214:
4213:Nuisance call
4211:
4209:
4206:
4204:
4201:
4200:
4198:
4194:
4188:
4185:
4183:
4180:
4178:
4175:
4173:
4170:
4168:
4165:
4163:
4160:
4158:
4155:
4153:
4152:Fibre-optical
4150:
4148:
4145:
4143:
4140:
4139:
4137:
4133:
4127:
4124:
4122:
4119:
4118:
4116:
4112:
4106:
4103:
4101:
4098:
4096:
4093:
4091:
4088:
4086:
4083:
4082:
4080:
4076:
4072:
4065:
4060:
4058:
4053:
4051:
4046:
4045:
4042:
4030:
4029:
4020:
4018:
4017:
4008:
4007:
4004:
3998:
3995:
3993:
3990:
3989:
3987:
3983:
3977:
3974:
3972:
3969:
3968:
3966:
3962:
3956:
3953:
3951:
3948:
3946:
3943:
3941:
3938:
3936:
3933:
3931:
3928:
3926:
3923:
3921:
3918:
3917:
3915:
3911:
3905:
3902:
3900:
3897:
3895:
3892:
3890:
3887:
3885:
3882:
3880:
3877:
3875:
3872:
3870:
3867:
3865:
3862:
3860:
3857:
3855:
3852:
3850:
3847:
3845:
3842:
3840:
3837:
3835:
3832:
3830:
3827:
3825:
3822:
3820:
3817:
3815:
3812:
3811:
3809:
3805:
3799:
3796:
3794:
3791:
3789:
3786:
3784:
3781:
3779:
3776:
3774:
3771:
3769:
3766:
3765:
3763:
3759:
3753:
3750:
3748:
3745:
3743:
3740:
3738:
3735:
3733:
3730:
3728:
3725:
3723:
3720:
3719:
3717:
3715:
3711:
3707:
3701:
3698:
3696:
3693:
3691:
3688:
3686:
3683:
3681:
3678:
3675:
3671:
3668:
3666:
3663:
3661:
3658:
3656:
3653:
3651:
3648:
3646:
3643:
3641:
3640:Monoblock LNB
3638:
3636:
3633:
3632:
3630:
3626:
3620:
3617:
3615:
3612:
3610:
3607:
3605:
3602:
3600:
3597:
3595:
3592:
3590:
3587:
3585:
3582:
3580:
3577:
3576:
3574:
3572:Main articles
3570:
3566:
3559:
3554:
3552:
3547:
3545:
3540:
3539:
3536:
3530:
3528:
3524:
3521:
3517:
3514:
3511:
3509:
3506:
3505:
3501:
3497:
3496:online review
3493:
3489:
3488:
3484:
3469:
3468:
3463:
3457:
3454:
3443:
3439:
3433:
3430:
3425:
3419:
3415:
3411:
3407:
3400:
3397:
3385:
3381:
3375:
3372:
3359:
3355:
3349:
3346:
3333:
3329:
3323:
3320:
3307:
3303:
3297:
3294:
3281:
3277:
3271:
3268:
3257:on 2013-08-15
3256:
3252:
3248:
3242:
3239:
3234:
3230:
3223:
3220:
3215:
3211:
3204:
3201:
3193:
3187:
3184:
3179:
3173:
3170:
3157:
3150:
3144:
3141:
3136:
3130:
3126:
3125:
3117:
3114:
3110:
3103:
3097:
3094:
3082:
3075:
3072:
3067:
3063:
3059:
3058:
3050:
3047:
3034:
3033:"Molniya 1-1"
3028:
3025:
3009:
3003:
3000:
2987:
2981:
2978:
2973:
2969:
2965:
2958:
2956:
2954:
2950:
2934:
2928:
2925:
2912:
2906:
2903:
2890:
2884:
2881:
2868:
2862:
2859:
2843:
2837:
2834:
2821:
2815:
2812:
2807:
2803:
2799:
2798:
2790:
2788:
2784:
2768:
2762:
2759:
2754:
2748:
2744:
2743:
2735:
2732:
2719:
2713:
2710:
2694:
2688:
2686:
2682:
2669:
2663:
2660:
2647:
2640:
2634:
2631:
2626:
2620:
2616:
2615:
2607:
2604:
2599:
2595:
2591:
2587:
2583:
2582:
2574:
2571:
2558:
2554:
2550:
2543:
2540:
2527:
2523:
2519:
2515:
2514:
2509:
2502:
2499:
2486:
2482:
2481:
2476:
2469:
2466:
2450:
2446:
2445:
2437:
2430:
2427:
2416:on 2015-09-05
2415:
2411:
2407:
2401:
2399:
2395:
2383:
2377:
2374:
2363:
2359:
2352:
2349:
2342:
2293:
2290:
2278:
2273:10 Nm/kg
2266:
2262:
2258:
2254:
2250:
2247: =
2246:
2243:
2239:
2236:
2233: =
2232:
2226:
2223:
2216:
2211:
2206:
2203:
2201:
2198:
2196:
2193:
2191:
2188:
2186:
2183:
2181:
2178:
2176:
2173:
2171:
2168:
2166:
2163:
2161:
2158:
2156:
2153:
2151:
2148:
2146:
2143:
2141:
2138:
2136:
2133:
2131:
2128:
2127:
2122:
2120:
2118:
2114:
2110:
2106:
2102:
2098:
2094:
2090:
2086:
2082:
2078:
2077:weather buoys
2074:
2070:
2066:
2063:
2055:
2053:
2051:
2043:
2039:
2035:
2031:
2023:
2019:
2015:
2011:
2007:
2003:
1999:
1995:
1991:
1987:
1983:
1979:
1973:
1967:
1959:
1957:
1955:
1951:
1945:
1937:
1935:
1933:
1928:
1924:
1920:
1916:
1911:
1910:Amateur radio
1906:
1899:Amateur radio
1898:
1896:
1893:
1891:
1885:
1877:
1875:
1873:
1869:
1865:
1860:
1855:
1849:
1845:
1841:
1837:
1828:
1826:
1818:
1813:
1809:
1800:
1798:
1794:
1790:
1786:
1782:
1778:
1774:
1770:
1762:
1758:
1753:
1751:
1747:
1743:
1739:
1736:
1733:The American
1731:
1729:
1721:
1717:
1713:
1705:
1701:
1699:
1695:
1691:
1687:
1683:
1679:
1671:
1667:
1663:
1661:
1657:
1653:
1647:
1645:
1641:
1637:
1633:
1627:
1619:
1617:
1615:
1609:
1607:
1603:
1599:
1598:Easter Island
1595:
1591:
1587:
1582:
1580:
1576:
1572:
1571:Earth station
1568:
1564:
1560:
1556:
1548:
1543:
1538:
1530:
1525:
1521:
1518:
1516:
1513:
1511:
1508:
1506:
1503:
1501:
1498:
1497:
1496:
1489:
1486:
1483:
1482:
1481:
1479:
1471:
1469:
1467:
1457:
1455:
1454:solar eclipse
1451:
1447:
1444:
1440:
1437:
1434:
1430:
1426:
1425:
1424:
1418:
1416:
1414:
1410:
1406:
1402:
1397:
1394:
1390:
1386:
1378:
1376:
1372:
1367:
1359:
1357:
1355:
1351:
1347:
1343:
1339:
1335:
1331:
1327:
1323:
1319:
1315:
1311:
1307:
1303:
1298:
1294:
1290:
1286:
1284:
1277:
1276:Molniya orbit
1270:Molniya orbit
1269:
1267:
1265:
1261:
1257:
1253:
1249:
1245:
1241:
1237:
1233:
1229:
1221:
1217:
1213:
1209:
1205:
1201:
1197:
1193:
1189:
1185:
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1177:
1173:
1169:
1166:
1162:
1158:
1154:
1151:
1150:Western Union
1147:
1143:
1139:
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1132:
1128:
1124:
1120:
1116:
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1111:
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838:
834:
829:
822:
820:
818:
814:
813:Molniya orbit
810:
806:
801:
799:
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785:
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769:
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664:
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656:
655:Project SCORE
647:
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621:
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543:
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521:
518:
513:
512:line of sight
509:
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357:
350:
349:Intergalactic
347:
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246:
244:
243:Space Shuttle
241:
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114:
107:
106:Mars missions
104:
102:
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79:
78:
75:
70:
69:
63:
59:
58:
55:
51:
47:
43:
42:
37:
32:
19:
6110:Space launch
6095:Interstellar
6061:Destinations
5830:Apollo–Soyuz
5779:Space diving
5764:Space toilet
5627:
5588:Applications
5505:Soviet Union
5465:Space policy
5460:Space launch
5054:Multiplexing
4929:Transmission
4894:Nikola Tesla
4884:Henry Sutton
4839:Samuel Morse
4769:Robert Hooke
4734:Amos Dolbear
4669:John Bardeen
4588:
4568:Telautograph
4518:
4472:Mobile phone
4427:Edholm's law
4410:social media
4343:Broadcasting
4249:Théâtrophone
4227:Applications
4146:
4135:Connectivity
4095:Mobile phone
4027:
4015:
3854:Intersputnik
3778:Dish Network
3608:
3564:
3526:
3491:
3471:. Retrieved
3466:
3456:
3445:. Retrieved
3441:
3432:
3405:
3399:
3388:. Retrieved
3386:. 2013-09-04
3383:
3374:
3362:. Retrieved
3348:
3336:. Retrieved
3331:
3322:
3310:. Retrieved
3306:the original
3296:
3284:. Retrieved
3280:the original
3270:
3259:. Retrieved
3255:the original
3250:
3241:
3232:
3222:
3213:
3203:
3186:
3172:
3160:. Retrieved
3155:
3143:
3123:
3116:
3108:
3096:
3084:. Retrieved
3074:
3056:
3049:
3037:. Retrieved
3027:
3015:. Retrieved
3002:
2990:. Retrieved
2986:"Early Bird"
2980:
2963:
2940:. Retrieved
2927:
2915:. Retrieved
2905:
2893:. Retrieved
2883:
2871:. Retrieved
2861:
2849:. Retrieved
2836:
2824:. Retrieved
2814:
2796:
2774:. Retrieved
2761:
2741:
2734:
2722:. Retrieved
2720:. NASA. 2020
2712:
2700:. Retrieved
2672:. Retrieved
2670:. NASA. 2020
2668:"Courier 1B"
2662:
2650:. Retrieved
2645:
2633:
2613:
2606:
2580:
2573:
2561:. Retrieved
2552:
2542:
2530:. Retrieved
2511:
2501:
2489:. Retrieved
2478:
2475:"Orbit Wars"
2468:
2456:. Retrieved
2442:
2429:
2418:. Retrieved
2414:the original
2409:
2386:. Retrieved
2376:
2365:. Retrieved
2361:
2351:
2292:
2287:10 lb).
2276:
2264:
2260:
2256:
2252:
2248:
2244:
2241:
2237:
2234:
2230:
2225:
2109:Argos system
2060:Near-ground
2059:
2006:Soviet Union
1975:
1947:
1908:
1894:
1887:
1856:
1829:
1801:
1754:
1735:Dish Network
1732:
1728:transponders
1702:
1664:
1648:
1629:
1610:
1594:Diego Garcia
1590:Saint Helena
1583:
1579:fiber-optics
1557:. The fixed
1552:
1526:Applications
1493:
1475:
1462:
1429:transponders
1422:
1398:
1382:
1373:
1369:
1306:transmission
1299:
1295:
1291:
1287:
1279:
1262:series, and
1225:
1220:transponders
1130:
1103:
1100:
1092:sidereal day
1085:
1047:
1035:
1031:
1027:
1004:
994:operated by
965:
951:
944:
940:
933:
909:
901:
888:
880:
866:
855:), with the
805:Soviet Union
802:
791:
770:
751:
729:
703:
675:
667:
652:
629:
615:
609:
607:
574:Soviet Union
563:
540:
534:
505:
432:
430:
372:Space forces
344:Interstellar
277:Space launch
125:
119:Applications
96:Space probes
6068:Sub-orbital
6003:Space probe
5869:New Shepard
5847:Shuttle–Mir
5606:Archaeology
5559:Space force
5542:Moon Treaty
5414:Spaceflight
5254:NPL network
4966:Radio waves
4904:Alfred Vail
4814:Hedy Lamarr
4799:Dawon Kahng
4759:Elisha Gray
4719:Yogen Dalal
4644:Nasir Ahmed
4578:Teleprinter
4442:Heliographs
4254:Video calls
4203:Missed call
4114:Accessories
3864:SED Systems
3798:1worldspace
3614:Transponder
3197:. Mar 2022.
3180:. Oct 2021.
3156:Arianespace
3086:November 6,
2596:. SP-4217.
2093:telecontrol
2087:or two-way
2081:radiosondes
2069:tide gauges
1846:. NASA and
1787:in Canada,
1785:Shaw Direct
1704:Free-to-air
1642:(DBS), and
1459:life-cycle.
1450:solar cells
1366:Polar orbit
1360:Polar orbit
1338:Vladivostok
1316:station to
1258:, with the
1174:) launched
593:transmitter
520:frequencies
508:radio waves
453:transmitter
445:transponder
329:Sub-orbital
253:Spaceplanes
202:Space probe
136:Exploration
54:Spaceflight
6225:Categories
6137:Launch pad
6128:Expendable
6078:Geocentric
6045:Solar sail
5988:Spaceplane
5948:Spacecraft
5742:Space suit
5720:commercial
5648:Television
5443:Space Race
5300:Antarctica
5259:Toasternet
5181:Television
4664:Paul Baran
4596:Television
4580:(teletype)
4573:Telegraphy
4551:transistor
4529:Phryctoria
4499:Photophone
4477:Smartphone
4467:Mass media
4105:Photophone
3829:Globalstar
3473:2023-08-18
3447:2020-12-21
3390:2013-09-18
3338:16 January
3312:16 January
3261:2013-09-19
2889:"Syncom 3"
2867:"Syncom 2"
2420:2016-02-10
2388:2016-02-10
2367:2016-02-10
2318:(that is,
2298:(that is,
2212:References
1992:, and the
1840:SPACEWAY-1
1752:channels.
1716:Galaxy 10R
1710:band. The
1682:live shots
1620:Television
1602:Antarctica
1330:Khabarovsk
1163:built for
1131:Early Bird
1127:Intelsat I
1002:coverage.
980:Globalstar
749:spectrum.
719:, and the
670:Courier 1B
657:, led by
564:The first
465:television
294:Expendable
289:Launch pad
179:Spacecraft
161:Telescopes
156:Settlement
151:Navigation
86:Space Race
6147:Spaceport
5998:Satellite
5715:Astronaut
5643:Telephone
5596:Astronomy
5517:Space law
5470:Australia
5284:Americas
5273:Locations
5244:Internet2
5005:Bandwidth
4709:Vint Cerf
4606:streaming
4584:Telephone
4524:Semaphore
4415:streaming
4218:Phone tag
4126:Caller ID
4071:Telephony
3635:SAT>IP
3302:"GSAT-14"
3162:27 August
3039:5 January
3017:5 January
2992:5 January
2942:4 January
2917:4 January
2895:3 January
2873:3 January
2851:4 January
2826:4 January
2776:3 January
2724:3 January
2702:3 January
2674:3 January
2652:2 January
2563:1 January
2532:1 January
2522:0886-2257
2491:1 January
2458:1 January
2410:Aerospace
2343:Citations
2089:telemetry
1994:FLTSATCOM
1954:broadband
1890:broadcast
1825:Primestar
1742:SuperDish
1686:backhauls
1632:bandwidth
1606:Greenland
1567:land line
1549:satellite
1531:Telephony
1419:Structure
1389:cis-lunar
1352:, called
1238:with the
837:Low Earth
693:microwave
689:reflector
598:Space Age
570:Sputnik 1
517:microwave
469:telephone
377:Companies
284:Spaceport
197:Satellite
141:Espionage
6199:Category
5864:Tiangong
5859:Shenzhou
5788:Programs
5633:Internet
5438:Timeline
5352:Category
5239:Internet
5229:CYCLADES
5146:Ethernet
5096:Concepts
5020:terminal
4971:wireless
4794:Bob Kahn
4637:Pioneers
4462:Internet
4353:Cable TV
4085:Landline
4016:Category
3884:Starlink
3879:Star One
3849:Intelsat
3844:Inmarsat
3834:Hispasat
3824:Eutelsat
3819:EchoStar
3695:Spacebus
3628:Hardware
3516:Archived
3384:NDTV.com
3358:Archived
2718:"Echo 1"
2598:Archived
2557:Archived
2526:Archived
2485:Archived
2449:Archived
2251:, where
2160:NewSpace
2123:See also
2119:access.
2105:METEOSAT
1960:Military
1950:Internet
1925:such as
1923:antennas
1668:use the
1656:Eutelsat
1614:teleport
1433:antennas
1318:downlink
1260:Spacebus
1242:series,
1240:Star Bus
1204:headends
1196:Freeform
1180:cable TV
1176:Satcom 1
1146:Westar 1
1119:Syncom 3
1094:, in an
1008:CASSIOPE
988:Starlink
863:to scale
859:and the
847:and its
798:PanAmSat
766:Syncom 3
758:Syncom 2
709:AT&T
551:inventor
481:military
477:internet
457:receiver
298:reusable
146:Military
46:a series
44:Part of
6073:Orbital
5874:Artemis
5805:Voskhod
5800:Mercury
5708:General
5448:Records
5433:History
5421:General
5372:Commons
5362:Outline
5315:Oceania
5234:FidoNet
5219:ARPANET
5032:circuit
4601:digital
4330:History
4028:Commons
3899:Turksat
3889:Telesat
3859:Iridium
3793:Allente
3773:DirecTV
3747:ISDB-S3
3742:DVB-S2X
3732:DVB-RCS
3286:9 April
3251:Iridium
3233:IAC2013
3062:Bibcode
2968:Bibcode
2911:"LES 1"
2802:Bibcode
2590:Bibcode
2332:
2320:
2312:
2300:
2062:in situ
1986:MILSTAR
1844:Anik F2
1789:Freesat
1777:DirecTV
1696:(BTV),
1660:Hotbird
1646:(FSS).
1561:relays
1547:Iridium
1385:LunaNet
1346:network
1334:Magadan
1326:Norilsk
1322:Siberia
1310:signals
1302:Molniya
1264:Astrium
1138:Anik A1
1106:DirecTV
1048:Telstar
1012:Orbcomm
976:Iridium
835:, from
809:Molniya
705:Telstar
620:reflect
611:passive
531:Origins
526:History
489:equator
334:Orbital
166:Tourism
74:History
6210:Portal
6203:
6192:
6008:Lander
5961:Rocket
5825:Skylab
5820:Apollo
5810:Gemini
5795:Vostok
5500:Russia
5310:Europe
5280:Africa
5264:Usenet
5224:BITNET
5161:Mobile
5037:packet
4546:MOSFET
4541:device
4338:Beacon
3945:SpaceX
3925:Boeing
3920:Airbus
3904:Viasat
3894:Tooway
3839:Hughes
3788:Sky UK
3737:DVB-S2
3722:DVB-SH
3645:DiSEqC
3420:
3364:11 May
3131:
3035:. NASA
2988:. NASA
2913:. NASA
2891:. NASA
2869:. NASA
2822:. NASA
2749:
2621:
2520:
2079:, and
2038:X-band
2010:GSAT-7
2002:Skynet
1988:, the
1872:LiveTV
1684:, and
1670:C band
1658:, and
1596:, and
1354:Orbita
1342:system
1314:uplink
1308:of TV
1214:, and
1198:) and
1129:, aka
996:SpaceX
928:
926:
779:. The
747:X band
681:Echo 1
616:active
479:, and
455:and a
435:is an
258:Vostok
6013:Rover
5815:Soyuz
5638:Radio
5495:Japan
5490:India
5475:China
5293:South
5288:North
5249:JANET
5186:Telex
5176:Radio
5015:Nodes
5010:Links
4931:media
4509:Radio
4494:Pager
4422:Drums
4388:video
4383:image
4373:audio
4196:Calls
4078:Types
3985:Lists
3930:INVAP
3727:S-DMB
3650:USALS
3195:(PDF)
3152:(PDF)
3105:(PDF)
3011:(PDF)
2936:(PDF)
2845:(PDF)
2770:(PDF)
2696:(PDF)
2642:(PDF)
2452:(PDF)
2439:(PDF)
2269:6.673
2217:Notes
2040:) or
1927:Yagis
1726:band
1720:AMC 3
1652:Astra
1565:from
1194:(now
1161:ATS-6
990:is a
869:orbit
861:Earth
781:LES-1
590:radio
473:radio
461:Earth
441:radio
6175:Pass
6130:and
5305:Asia
5191:UUCP
5151:ISDN
4187:VoIP
4177:PSTN
4172:POTS
4162:ISDN
3418:ISBN
3366:2012
3340:2014
3314:2014
3288:2020
3164:2020
3129:ISBN
3088:2022
3041:2021
3019:2021
2994:2021
2944:2021
2919:2021
2897:2021
2875:2021
2853:2021
2828:2021
2778:2021
2747:ISBN
2726:2021
2704:2021
2676:2021
2654:2021
2619:ISBN
2586:NASA
2565:2021
2534:2021
2518:ISSN
2493:2021
2460:2021
2240:and
2103:and
2101:GOES
2091:and
2050:band
2030:band
2024:and
1998:NATO
1990:DSCS
1932:X.25
1848:ISRO
1836:band
1817:TVRO
1797:DSTV
1791:and
1783:and
1769:band
1750:HDTV
1718:and
1678:band
1604:and
1409:Mars
1336:and
1165:NASA
978:and
677:NASA
614:and
580:and
568:was
506:The
296:and
5842:Mir
5196:WAN
5166:NGN
5156:LAN
4437:Fax
4378:DCT
3950:SSL
3869:SES
3410:doi
3214:ESA
2113:SCD
2042:EHF
2034:SHF
2014:UHF
1919:VHF
1917:or
1915:UHF
1793:Sky
1746:FCC
1738:DBS
1545:An
1348:of
1216:CBS
1212:NBC
1208:ABC
1192:CBN
1188:HBO
1186:),
1184:TBS
1172:SES
1148:by
1098:).
1055:O3b
756:'s
744:SHF
738:'s
691:of
499:in
6227::
3714:TV
3712:/
3440:.
3416:.
3382:.
3330:.
3249:.
3231:.
3212:.
3154:.
2952:^
2786:^
2684:^
2644:.
2584:.
2555:.
2551:.
2524:.
2516:.
2510:.
2483:.
2477:.
2441:.
2408:.
2397:^
2360:.
2275:;
2249:GM
2238:GM
2075:,
2071:,
2020:,
2016:,
1755:A
1730:.
1714:,
1654:,
1592:,
1588:,
1441:A
1431:,
1415:.
1332:,
1328:,
1266:.
1246:,
1234:,
1210:,
1190:,
1014:.
934:A
600:.
475:,
471:,
467:,
431:A
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5406:e
5399:t
5392:v
5323:)
5319:(
4314:e
4307:t
4300:v
4063:e
4056:t
4049:v
3676:)
3672:(
3557:e
3550:t
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3476:.
3450:.
3426:.
3412::
3393:.
3368:.
3342:.
3316:.
3290:.
3264:.
3235:.
3216:.
3166:.
3137:.
3090:.
3068:.
3064::
3043:.
3021:.
2996:.
2974:.
2970::
2946:.
2921:.
2899:.
2877:.
2855:.
2830:.
2808:.
2804::
2780:.
2755:.
2728:.
2706:.
2678:.
2656:.
2627:.
2592::
2567:.
2536:.
2495:.
2462:.
2423:.
2391:.
2370:.
2334:)
2326:/
2314:)
2306:/
2285:Ă—
2281:Ă—
2277:M
2271:Ă—
2265:G
2261:V
2257:T
2253:R
2245:R
2242:V
2235:T
2231:R
2048:a
2046:K
2028:u
2026:K
2022:C
2018:F
1852:a
1834:a
1832:K
1821:u
1804:u
1767:u
1765:K
1724:u
1708:u
1676:u
1674:K
1167:.
843:(
420:e
413:t
406:v
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