|
NigComSat
Nigerian Communications Satellite (NIGCOMSAT) Limited is a company under the supervision of the Federal Ministry of Communications. Satellites NigComSat-1 NigComSat-1, a Nigerian satellite ordered and built in China in 2004, was Nigeria's second satellite and Africa's first communication satellite. It was launched on 13 May 2007, aboard a Chinese Long March 3B carrier rocket, from the Xichang Satellite Launch Centre in China. The spacecraft was operated by NigComSat and the Nigerian Space Agency, NASRDA. On 11 November 2008, NigComSat-1 failed in orbit after running out of power due to an anomaly in its solar array. It was based on the Chinese DFH-4 satellite bus, and carries a variety of transponders: 4 C band; 14 Ku band; 8 Ka band; and 2 L band. It was designed to provide coverage to many parts of Africa, and the Ka band transponders would also cover Italy. On 10 November 2008 (0900 GMT), the satellite was reportedly switched off for analysis and to avoid a possible col ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NASRDA
The National Space Research and Development Agency (NASRDA) is the national space agency of Nigeria. It is a parastatal under Federal Ministry of Science and Technology. The agency is based in the Nigerian capital city of Abuja in the Lugbe district and has a ground receiving station, among various other sites. It has had cooperation in space technology with the United Kingdom, China, Ukraine and Russia. The agency has struggled with meeting its financial plans and some of its facilities are rundown. Despite this, the space agency is one of the most advanced space agencies in Africa, boasting of four satellites and very grand ambitions. Nigeria's satellites have been praised for their high-resolution images. NASRDA is host to one of UN-SPIDER's Regional Support Offices (RSO) in Africa. History NASRDA was established on 5 May 1999, after a preparation period since in 1998 by Nigerian president Olusegun Obasanjo and the Nigerian government with a primary objective of establishing a " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NigComSat-1
NigComSat-1 was a Nigerian communication satellite. The initial contract to build the satellite was signed in 2004. It was launched in China by Nasrda and became the third African geosynchronous communication satellite, when it was launched at 16:01 UTC on 13 May 2007, aboard a Chinese Long March 3B carrier rocket, from the Xichang Satellite Launch Centre in China. The spacecraft was operated by Nigerian Communications Satellite Ltd (NIGCOMSAT). On November 11, 2008, NigComSat-1 failed in orbit after running out of power due to an anomaly in its solar array. Launch The satellite, which is the third Nigerian satellite to be placed into orbit, was launched into a geosynchronous transfer orbit and subsequently it was successfully inserted into a geosynchronous orbit, positioned at 42.5oE. It had a launch mass of 5,150 kg, and had an expected service life of 15 years. Specifications It was based on the Chinese DFH-4 satellite bus, and carries a variety of transponders: *4 C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Long March 3B
The Long March 3B (, ''Chang Zheng 3B''), also known as the CZ-3B and LM-3B, is a Chinese orbital launch vehicle. Introduced in 1996, it is launched from Launch Area 2 and 3 at the Xichang Satellite Launch Center in Sichuan. A three-stage rocket with four strap-on liquid rocket boosters, it is currently the second most powerful member of the Long March (rocket family), Long March rocket family after the Long March 5 and the heaviest of the Long March 3 rocket family, and is mainly used to place communications satellites into geosynchronous orbits. An enhanced version, the Long March 3B/E or G2, was introduced in 2007 to increase the rocket's geostationary transfer orbit (GTO) cargo capacity and lift heavier geosynchronous orbit (GEO) communications satellites. The Long March 3B also served as the basis for the medium-capacity Long March 3C, which was first launched in 2008. , the Long March 3B, 3B/E and 3B/G5 have conducted 82 successful launches, plus 2 failures and 2 partial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nigeria
Nigeria ( ), , ig, Naìjíríyà, yo, Nàìjíríà, pcm, Naijá , ff, Naajeeriya, kcg, Naijeriya officially the Federal Republic of Nigeria, is a country in West Africa. It is situated between the Sahel to the north and the Gulf of Guinea to the south in the Atlantic Ocean. It covers an area of , and with a population of over 225 million, it is the most populous country in Africa, and the world's sixth-most populous country. Nigeria borders Niger in the north, Chad in the northeast, Cameroon in the east, and Benin in the west. Nigeria is a federal republic comprising of 36 states and the Federal Capital Territory, where the capital, Abuja, is located. The largest city in Nigeria is Lagos, one of the largest metropolitan areas in the world and the second-largest in Africa. Nigeria has been home to several indigenous pre-colonial states and kingdoms since the second millennium BC, with the Nok civilization in the 15th century BC, marking the first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abuja
Abuja () is the capital and eighth most populous city of Nigeria. Situated at the centre of the country within the Federal Capital Territory (FCT), it is a planned city built mainly in the 1980s based on a master plan by International Planning Associates (IPA), a consortium of three American planning and architecture firms made up of Wallace, Roberts, McHarg & Todd (WRMT – a group of architects) as the lead, Archisystems International (a subsidiary of the Howard Hughes Corporation), and Planning Research Corporation. The Central Business District of Abuja was designed by Japanese architect Kenzo Tange. It replaced Lagos, the country's most populous city, as the capital on 12 December 1991. Abuja's geography is defined by Aso Rock, a monolith left by water erosion. The Presidential Complex, National Assembly, Supreme Court and much of the city extend to the south of the rock. Zuma Rock, a monolith, lies just north of the city on the expressway to Kaduna. At the 2006 ce ... [...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 in the microwave range of frequencies ranging from 4.0 to 8.0 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 Wi-Fi devices, some cordless telephones, as well as some Radar and weather radar systems. Use in satellite communication The communications C band was the first frequency band that was allocated for commercial telecommunications via satellites. The same frequencies were already in use for terrestrial microwave radio relay chains. Nearly all C-band communication satellites use the band of frequencies from 3.7 to 4.2 GHz for their downlinks, and the band of frequencies from 5.925 to 6.425 GHz for their uplinks. Note that by using the band from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agence France-Presse
Agence France-Presse (AFP) is a French international news agency headquartered in Paris, France. Founded in 1835 as Havas, it is the world's oldest news agency. AFP has regional headquarters in Nicosia, Montevideo, Hong Kong and Washington, D.C., and news bureaus in 151 countries in 201 locations. AFP transmits stories, videos, photos and graphics in French, English, Arabic, Portuguese, Spanish, and German. History Agence France-Presse has its origins in the Agence Havas, founded in 1835 in Paris by Charles-Louis Havas, making it the world's oldest news service. The agency pioneered the collection and dissemination of news as a commodity, and had established itself as a fully global concern by the late 19th century. Two Havas employees, Paul Julius Reuter and Bernhard Wolff, set up their own news agencies in London and Berlin respectively. In 1940, when German forces occupied France during World War II, the news agency was taken over by the authorities and renamed "Office fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
L Band
The L band is the Institute of Electrical and Electronics Engineers (IEEE) designation for the range of frequencies in the radio spectrum from 1 to 2 gigahertz (GHz). This is at the top end of the ultra high frequency (UHF) band, at the lower end of the microwave range. Applications Mobile service In Europe, the Electronic Communications Committee (ECC) of the European Conference of Postal and Telecommunications Administrations (CEPT) has harmonized part of the L band (1452–1492 MHz), allowing individual countries to adopt this spectrum for terrestrial mobile/fixed communications networks supplemental downlink (MFCN SDL). By means of carrier aggregation, an LTE-Advanced or UMTS/HSDPA base station could use this spectrum to provide additional bandwidth for communications from the base station to the mobile device; i.e., in the downlink direction. In the Americas, mobile services are operated between the 1.7 GHz to 2.1 GHz range in the PCS and AWS bands. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ka Band
The Ka band (pronounced as either "kay-ay band" or "ka band") is a portion of the microwave part of the electromagnetic spectrum defined as frequencies in the range 26.5–40 gigahertz (GHz), i.e. wavelengths from slightly over one centimeter down to 7.5 millimeters. The band is called Ka, short for "K-above" because it is the upper part of the original NATO K band, which was split into three bands 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. The 30/20 GHz band is used in communications satellite uplinks in either the 27.5 GHz and 31 GHz bands, and high-resolution, close-range targeting radars aboard military airplanes. Some frequencies in this radio band are used for vehicle speed detection by law enforcement. The Kepler Mission used this frequency range to downlink the scientific data collected by the space telescope. The designation "Ka ... [...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 german: Kurz-unten), 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DFH-4
Dongfanghong () was a satellite program of the People's Republic of China. The program started in August 1965 as Project 651—a less ambitious successor to the earlier Project 581—with the goal of launching a satellite heavier than both Sputnik 1 and Explorer 1 into space, and developing all the necessary technologies to do so. History In 1958, the Chinese Academy of Science proposed Project 581 which included a plan to launch a satellite into space before 1 October 1959. The project was troubled due to the country's lack of expertise in the field of rocketry. On 21 January 1959, Zhang Jingfu, who was in charge in the satellite research program, postponed the project to allow effort to be put into developing more basic technologies, such as sounding rocketry. In December 1964, during the 3rd National People's Congress, Zhao Jiuzhang suggested that the work on satellites be resumed. In August 1968, the Central Special Committee approved Chinese Academy of Science's plan, wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transponder
In telecommunications, a transponder is a device that, upon receiving a signal, emits a different signal in response. The term is a blend word, blend of ''transmitter'' and ''responder''. In air navigation or radio frequency identification, a Transponder (aeronautics), flight transponder is an automated transceiver in an aircraft that emits a coded identifying signal in response to an interrogating received signal. In a communications satellite, a Transponder (satellite communications), satellite transponder receives signals over a range of uplink frequencies, usually from a satellite ground station; the transponder amplifies them, and re-transmits them on a different set of downlink frequencies to receivers on Earth, often without changing the content of the received signal or signals. Satellite/broadcast communications A communications satellite’s Communication channel, channels are called transponders because each is a separate transceiver or repeater. With digital video d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
