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Intelsat VI
The Intelsat VI series of satellites were the 8th generation of geostationary communications satellites for the Intelsat Corporation. Designed and built by Hughes Aircraft Company (HAC) in 1983-1991, there were five VI-series satellites built: 601, 602, 603, 604, and 605. Design The Intelsat VI satellite was designed as a spinning satellite as had previous satellite designs. The main body of the spacecraft was spun at 30 revolutions per minute (rpm) to impart gyroscopic stability to the satellite in the Earth's gravitation field. A section of the spacecraft supporting the communications payload and antenna was de-spun to allow the antenna to point at the desired location on the earth. The Intelsat VI series combined two design features of previous HAC satellites, larger solar array and wide body design. The HS376 extended power spinner satellite had an extra concentric cylindrical solar array which deployed after launch to increase the power generating capability of the satelli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intelsat
Intelsat S.A. (formerly Intel-Sat, Intelsat) is a Luxembourgish-American multinational satellite services provider with corporate headquarters in Luxembourg and administrative headquarters in Tysons, Virginia, United States. Originally formed as International Telecommunications Satellite Organization (''ITSO'', or Intelsat), from 1964 to 2001, it was an intergovernmental consortium owning and managing a constellation of communications satellites providing international telecommunications and broadcast services. In March 2023, rival satellite operator SES confirmed that it was in talks about a merger with Intelsat but in June 2023, it was announced that these discussions had ended. On 30 April 2024, SES announced that an agreement had been reached to acquire Intelsat for US$3.1 billion, with the transaction expected to close in the second half of 2025. As of June 2022, Intelsat operated a fleet of 52 communications satellites which was then one of the world's largest fleet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ku-band
The Ku band () is the portion of the electromagnetic spectrum in the microwave range of frequencies from 12 to 18 gigahertz (GHz). The symbol is short for "K-under" (originally ), because it is the lower part of the original NATO K band, which was split into three bands (Ku, K, and Ka) because of the presence of the atmospheric water vapor resonance peak at 22.24 GHz, (1.35 cm) which made the center unusable for long range transmission. In radar applications, it ranges from 12 to 18 GHz according to the formal definition of radar frequency band nomenclature in IEEE Standard 521–2002. Ku band is primarily used for satellite communications, most notably the downlink used by direct broadcast satellites to broadcast satellite television, and for specific applications such as NASA's Tracking Data Relay Satellite used for International Space Station (ISS) communications and SpaceX Starlink satellites. Ku band satellites are also used for backhauls and pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Shuttle
The Space Shuttle is a retired, partially reusable launch system, reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program name was the Space Transportation System (STS), taken from the 1969 plan led by U.S. vice president Spiro Agnew for a system of reusable spacecraft where it was the only item funded for development. The first (STS-1) of four orbital test flights occurred in 1981, leading to operational flights (STS-5) beginning in 1982. Five complete Space Shuttle orbiter vehicles were built and flown on a total of 135 missions from 1981 to 2011. They launched from the Kennedy Space Center (KSC) in Florida. Operational missions launched numerous satellites, interplanetary probes, and the Hubble Space Telescope (HST), conducted science experiments in orbit, participated in the Shuttle–Mir program, Shuttle-''Mir'' program with Russia, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commercial Titan III
The Commercial Titan III, also known as CT-3 or CT-III, was an American expendable launch system, developed by Martin Marietta during the late 1980s and flown four times during the early 1990s. It was derived from the Titan 34D, and was originally proposed as a medium-lift expendable launch system for the US Air Force, who selected the Delta II instead. Development was continued as a commercial launch system, and the first rocket flew in 1990. Due to higher costs than contemporary rockets such as the Ariane 4, orders were not forthcoming, and the CT-3 was retired in 1992. The Commercial Titan III differed from the Titan 34D in that it had a stretched second stage, and a larger payload fairing to accommodate dual satellite payloads. All four launches occurred from LC-40 at Cape Canaveral Air Force Station. The first carried two communications satellites, Skynet 4A and JCSAT-2, and was launched at 00:07 UTC on 1 January 1990, which was 19:07 local time on 31 December 1989. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frisbee
A frisbee (pronounced ), also called a flying disc or simply a disc, is a gliding toy or sporting item generally made of injection-molded plastic and roughly in diameter with a pronounced lip. It is used recreationally and competitively for throwing and catching, as in flying disc games. The shape of the disc is an airfoil in cross-section which allows it to fly by reducing the drag and increasing lift as it moves through the air, compared to a flat plate. Spinning the disc imparts a stabilizing gyroscopic force, allowing it to be both aimed with accuracy and thrown for distance. A wide range is available of flying disc variants. Those for disc golf are usually smaller but denser compared to ultimate frisbee, and tailored for particular flight profiles to increase or decrease stability and distance. The longest recorded disc throw is by David Wiggins Jr. with a distance of . Disc dog sports use relatively slow-flying discs made of more pliable material to better resist a do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perigee
An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. The line of apsides (also called apse line, or major axis of the orbit) is the line connecting the two extreme values. Apsides pertaining to orbits around different bodies have distinct names to differentiate themselves from other apsides. Apsides pertaining to geocentric orbits, orbits around the Earth, are at the farthest point called the ''apogee'', and at the nearest point the ''perigee'', like with orbits of satellites and the Moon around Earth. Apsides pertaining to orbits around the Sun are named ''aphelion'' for the farthest and ''perihelion'' for the nearest point in a heliocentric orbit. Earth's two apsides are the farthest point, ''aphelion'', and the nearest point, ''perihelion'', of its orbit around the host Sun. The terms ''aphelion'' and ''perihelion'' apply in the same way to the orbits of Jupiter and the other planets, the comets, and the asteroids of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telemetry
Telemetry is the in situ collection of measurements or other data at remote points and their automatic transmission to receiving equipment (telecommunication) for monitoring. The word is derived from the Greek roots ''tele'', 'far off', and ''metron'', 'measure'. Systems that need external instructions and data to operate require the counterpart of telemetry: telecommand. Although the term commonly refers to wireless data transfer mechanisms (e.g., using radio, ultrasonic, or infrared systems), it also encompasses data transferred over other media such as a telephone or computer network, optical link or other wired communications like power line carriers. Many modern telemetry systems take advantage of the low cost and ubiquity of GSM networks by using SMS to receive and transmit telemetry data. A ''telemeter'' is a physical device used in telemetry. It consists of a sensor, a transmission path, and a display, recording, or control device. Electronic devices are widely u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Time Division Multiple Access
Time-division multiple access (TDMA) is a channel access method for shared-medium networks. It allows several users to share the same frequency channel by dividing the signal into different time slots. The users transmit in rapid succession, one after the other, each using its own time slot. This allows multiple stations to share the same transmission medium (e.g. radio frequency channel) while using only a part of its channel capacity. Dynamic TDMA is a TDMA variant that dynamically reserves a variable number of time slots in each frame to variable bit-rate data streams, based on the traffic demand of each data stream. TDMA is used in digital 2G cellular systems such as Global System for Mobile Communications (GSM), IS-136, Personal Digital Cellular (PDC) and iDEN, in the Maritime Automatic Identification System, and in the Digital Enhanced Cordless Telecommunications (DECT) standard for portable phones. TDMA was first used in satellite communication systems by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C Band (IEEE)
The C band is a designation by the Institute of Electrical and Electronics Engineers (IEEE) for a portion of the electromagnetic spectrum The electromagnetic spectrum is the full range of electromagnetic radiation, organized by frequency or wavelength. The spectrum is divided into separate bands, with different names for the electromagnetic waves within each band. From low to high ... in the microwave range of frequencies ranging from 4.0 to 8.0 Hertz, gigahertz (GHz). However, the U.S. Federal Communications Commission C band proceeding and auction, designated 3.7–4.2 GHz as C band. The C band is used for many satellite communications transmissions, some Cordless telephone, cordless telephones, as well as some Surveillance, radar and Weather radar, weather radar systems. The C band contains the 5.725 - 5.875 GHz ISM band allowing unlicensed use by low power devices, such as garage door openers, wireless doorbells, and baby monitors. A very large us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hughes Aircraft
The Hughes Aircraft Company was a major American aerospace company, aerospace and defense contractor founded on February 14, 1934 by Howard Hughes in Glendale, California, as a division of the Hughes Tool Company. The company produced the Hughes H-4 Hercules aircraft, the atmospheric entry probe carried by the Galileo (spacecraft), ''Galileo'' spacecraft, and the AIM-4 Falcon guided missile. Hughes Aircraft was founded to build Hughes' Hughes H-1 Racer, H-1 Racer world speed record aircraft, and later modified other aircraft for his transcontinental and global circumnavigation speed record flights. The company relocated to Culver City, California, in 1940 and began manufacturing aircraft parts as a subcontractor. Hughes attempted to mold it into a major military aircraft manufacturer during World War II. However, its early military projects ended in failure, with millions of dollars in U.S. government funds expended for only a handful of prototypes, resulting in a highly publiciz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Waveguide
A waveguide is a structure that guides waves by restricting the transmission of energy to one direction. Common types of waveguides include acoustic waveguides which direct sound, optical waveguides which direct light, and radio-frequency waveguides which direct electromagnetic waves other than light like radio waves. Without the physical constraint of a waveguide, waves would expand into three-dimensional space and their intensities would decrease according to the inverse square law. There are different types of waveguides for different types of waves. The original and most common meaning is a hollow conductive metal pipe used to carry high frequency radio waves, particularly microwaves. Dielectric waveguides are used at higher radio frequencies, and transparent dielectric waveguides and optical fibers serve as waveguides for light. In acoustics, air ducts and horns are used as waveguides for sound in musical instruments and loudspeakers, and specially-shaped metal rod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
