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N-STAR B
N-STAR b, was a geostationary communications satellite originally ordered by a consortium including NTT DoCoMo and JSAT Corporation, and later fully acquired by JSAT, which was merged into SKY Perfect JSAT Group. It was designed and manufactured by Space Systems/Loral on the SSL 1300 platform. It had a launch weight of , and a 10-year design life. Its payload is composed of 6 C-band, 11 Ka-band, 8 Ku-band and 1 S-band transponders. History N-Star was created as a joint venture between JSAT, Nippon Telegraph and Telephone (NTT), NTT Communications and NTT DoCoMo for the supply of these latter two ''WIDESTAR'' satellite telephone and data packet service. JSAT would handle the satellite side of business and NTT DoCoMo would operate the payload. Two identical satellites were ordered on 1992 from Space Systems Loral, N-STAR a and N-STAR b, for 1995 and 1996 on orbit delivery. They would be "switchboards in the sky" having S-band, C-band, Ka-band and Ku-band payload. N-STAR ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communications Satellite
A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. Communications satellites are used for television, telephone, radio, internet, and military applications. Many communications satellites are in geostationary orbit above the equator, so that the satellite appears stationary at the same point in the sky; therefore the satellite dish antennas of ground stations can be aimed permanently at that spot and do not have to move to track the satellite. Others form satellite constellations in low Earth orbit, where antennas on the ground have to follow the position of the satellites and switch between satellites frequently. The high frequency radio waves used for telecommunications links travel by line of sight and so are obstructed by the curve of the Earth. The purpose of communications sate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N-STAR A
N-STAR a, was a geostationary communications satellite originally ordered by a consortium including NTT DoCoMo and JSAT Corporation, and later fully acquired by JSAT, which was merged into SKY Perfect JSAT Group. It was designed and manufactured by Space Systems/Loral on the SSL 1300 platform. It had a launch weight of , and a 10-year design life. Its payload is composed of 6 C-band, 11 Ka-band, 8 Ku-band and 1 S-band transponders. History N-Star was created as a joint venture between JSAT, Nippon Telegraph and Telephone (NTT), NTT Communications and NTT DoCoMo for the supply of these latter two ''WIDESTAR'' satellite telephone and data packet service. JSAT would handle the satellite side of business and NTT DoCoMo would operate the payload. Two identical satellites were ordered on 1992 from Space Systems Loral, N-STAR a and N-STAR b, for 1995 and 1996 on orbit delivery. They would be "switchboards in the sky" having S-band, C-band, Ka-band and Ku-band payload. N-STAR a w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spacecraft Launched In 1996
A spacecraft is a vehicle or machine designed to fly in outer space. A type of artificial satellite, spacecraft are used for a variety of purposes, including communications, Earth observation, meteorology, navigation, space colonization, planetary exploration, and transportation of humans and cargo. All spacecraft except single-stage-to-orbit vehicles cannot get into space on their own, and require a launch vehicle (carrier rocket). On a sub-orbital spaceflight, a space vehicle enters space and then returns to the surface without having gained sufficient energy or velocity to make a full Earth orbit. For orbital spaceflights, spacecraft enter closed orbits around the Earth or around other celestial bodies. Spacecraft used for human spaceflight carry people on board as crew or passengers from start or on orbit ( space stations) only, whereas those used for robotic space missions operate either autonomously or telerobotically. Robotic spacecraft used to support scientific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellites Using The SSL 1300 Bus
A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioisotope thermoelectric generators (RTGs). Most satellites also have a method of communication to ground stations, called transponders. Many satellites use a standardized bus to save cost and work, the most popular of which is small CubeSats. Similar satellites can work together as a group, forming constellations. Because of the high launch cost to space, satellites are designed to be as lightweight and robust as possible. Most communication satellites are radio relay stations in orbit and carry dozens of transponders, each with a bandwidth of tens of megahertz. Satellites are placed from the surface to orbit by launch vehicles, high enough to avoid orbital decay by the atmosphere. Satellites can then change or maintain the orbit by propul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communications Satellites In Geostationary Orbit
Communication (from la, communicare, meaning "to share" or "to be in relation with") is usually defined as the transmission of information. The term may also refer to the message communicated through such transmissions or the field of inquiry studying them. There are many disagreements about its precise definition. John Peters argues that the difficulty of defining communication emerges from the fact that communication is both a universal phenomenon and a specific discipline of institutional academic study. One definitional strategy involves limiting what can be included in the category of communication (for example, requiring a "conscious intent" to persuade). By this logic, one possible definition of communication is the act of developing meaning among entities or groups through the use of sufficiently mutually understood signs, symbols, and semiotic conventions. An important distinction is between verbal communication, which happens through the use of a language, and non ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JCSAT-5A
JCSAT-5A or N-STAR d, known as JCSAT-9 before launch, is a geostationary communications satellite operated by SKY Perfect JSAT Group (JSAT) which was designed and manufactured by Lockheed Martin on the A2100 platform. Satellite description The spacecraft was designed and manufactured by Lockheed Martin on the A2100-AX satellite bus. It had a launch mass of and a 12-year design life. It would provide communications services throughout Japan and Asia and for NTT DoCoMo. As most satellites based on the A2100-AX platform, it uses a LEROS-1C liquid apogee engine (LAE) for orbit raising. Its solar panels span when fully deployed and, with its antennas in fully extended configuration it is wide. Its payload is composed of eight 54 MHz and twelve 36 MHz Ku-band transponders, twenty 36 MHz C-band transponders and one S-band beam. The Ku-band transponders have a TWTA output power of 110 watts, the C-band of 45 watts and the S beam of 130 watts. History On 30 April ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NTT Communications
, or NTT Com, is a Japanese telecommunications company which operates an international network in over 190 countries/regions, with locations in more than 70 countries/regions. The company has approximately 5,500 employees (NTT Communications Group: 11,500 employees) as of March 2020. Its headquarters is located in the Otemachi Place West tower, Otemachi, Chiyoda, Tokyo. NTT Communications Corporation was founded in July 1999 as the wholly owned subsidiary of Nippon Telegraph & Telephone (NTT) Corp, and is one of the largest telecom companies in Japan and globally. NTT Communications provides network management, telecommunication services such as VPN, and communications technology (ICT) services including cloud, consulting, and managed services for companies and government agencies. History 1996-2005 Founding and early years In 1996, several new policies were issued for Telecommunications Law, and as a result of this policy changing NTT Communications Corporation was esta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nippon Telegraph And Telephone
, commonly known as NTT, is a Japanese telecommunications company headquartered in Tokyo, Japan. Ranked 55th in Fortune Global 500, ''Fortune'' Global 500, NTT is the fourth largest telecommunications company in the world in terms of revenue, as well as the third largest publicly traded company in Japan after Toyota and Sony, as of June 2022. The company is incorporated pursuant to the NTT Law (). The purpose of the company defined by the law is to own all the shares issued by Nippon Telegraph and Telephone East Corporation (NTT East) and Nippon Telegraph and Telephone West Corporation (NTT West) and to ensure proper and stable provision of telecommunications services all over Japan including remote rural areas by these companies as well as to conduct research relating to the telecommunications technologies that will form the foundation for telecommunications. On 1 July 2019, NTT Corporation launched NTT Ltd., an $11 billion de facto holding company business consisting of 28 brand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transponder (satellite Communications)
A communications satellite's transponder is the series of interconnected units that form a communications channel between the receiving and the transmitting antennas. It is mainly used in satellite communication to transfer the received signals. A transponder is typically composed of: * an input band-limiting device (an input band-pass filter), * an input low-noise amplifier (LNA), designed to amplify the signals received from the Earth station (normally very weak, because of the large distances involved), * a frequency translator (normally composed of an oscillator and a frequency mixer) used to convert the frequency of the received signal to the frequency required for the transmitted signal, * an output band-pass filter, * a power amplifier (this can be a traveling-wave tube or a solid-state amplifier). Most communication satellites are radio relay stations in orbit and carry dozens of transponders, each with a bandwidth of tens of megahertz. Most transponders operate on a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JSAT Corporation
JSAT Corporation (JSAT) was the first private Japanese satellite operator, which owned the JSAT satellites, as well as operated and partially owned the N-Star with NTT DoCoMo. Its origins can be traced to the funding of Japan Communications Satellite Company (JCSAT) and Satellite Japan Corporation in 1985. Both companies merged into Japan Satellite Systems Inc. in 1993. In 2000 the company was renamed as JSAT Corporation and was listed in the First Section of the Tokyo Stock Exchange. On September 1, 2008, the company was merged into the SKY Perfect JSAT Group. History With the opening of the Japanese satellite communications market to private investment, Japan Communications Satellite Company (JCSAT) and Satellite Japan Corporation were founded in 1985. In June of the same year, JCSAT awarded an order to Hughes Space and Communications for two identical satellites, JCSAT-1 and JCSAT-2, based on the spin-stabilized HS-393 satellite bus. JCSAT-1, the first commercial Japane ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communications Satellite
A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. Communications satellites are used for television, telephone, radio, internet, and military applications. Many communications satellites are in geostationary orbit above the equator, so that the satellite appears stationary at the same point in the sky; therefore the satellite dish antennas of ground stations can be aimed permanently at that spot and do not have to move to track the satellite. Others form satellite constellations in low Earth orbit, where antennas on the ground have to follow the position of the satellites and switch between satellites frequently. The high frequency radio waves used for telecommunications links travel by line of sight and so are obstructed by the curve of the Earth. The purpose of communications sate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
