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O3b MPOWER
O3b mPOWER is a communications satellite system currently under construction and deployment. The first two satellites were launched on 16 December 2022 and commercial service is expected to begin in Q3 2023. Owned and operated by SES, O3b mPOWER initially comprises 11 high-throughput and low- latency satellites in a medium Earth orbit (MEO), along with ground infrastructure and intelligent software, to provide multiple terabits of global broadband connectivity for applications including cellular backhaul to remote rural locations and simultaneous international IP trunking.''SES building a 10-terabit O3b mPower constellation'' SpaceNews, 11 September 2017, Accessed 25 August 2020 [...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] |
Internet Protocol
The Internet Protocol (IP) is the network layer communications protocol in the Internet protocol suite for relaying datagrams across network boundaries. Its routing function enables internetworking, and essentially establishes the Internet. IP has the task of delivering packets from the source host to the destination host solely based on the IP addresses in the packet headers. For this purpose, IP defines packet structures that encapsulate the data to be delivered. It also defines addressing methods that are used to label the datagram with source and destination information. IP was the connectionless datagram service in the original Transmission Control Program introduced by Vint Cerf and Bob Kahn in 1974, which was complemented by a connection-oriented service that became the basis for the Transmission Control Protocol (TCP). The Internet protocol suite is therefore often referred to as ''TCP/IP''. The first major version of IP, Internet Protocol Version 4 (IPv4), is the do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Princess Cruises
Princess Cruises is an American cruise line owned by Carnival Corporation & plc. The company is incorporated in Bermuda and its headquarters are in Santa Clarita, California, Santa Clarita, California. As of 2021, it is the List of cruise lines#List of cruise lines by size, second largest cruise line by net revenue. It was previously a subsidiary of P&O Princess Cruises, and is currently under Holland America Group within Carnival Corporation & plc, which holds executive control over the Princess Cruises brand. The line has 15 ships cruising global itineraries that are marketed to both American and international passengers. The company was made famous by the American television series ''The Love Boat'', in which its ship ''MS Pacific, Pacific Princess'' was featured. Since her introduction in 2019, ''Sky Princess (2019), Sky Princess'' has operated as the line's flagship. History Early years: 1965–1974 Princess Cruises began in 1965, when founder Stanley McDonald chartered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SES-17
SES-17, is a high throughput all electric geostationary communications satellite owned and operated by SES S.A., and designed and manufactured by Thales Alenia Space. Launched on 24 October 2021 from Centre Spatial Guyanais (CSG), in Kourou, French Guiana by an Ariane 5ECA launch vehicle, SES-17 was positioned at 67.1° west in May 2022 and, after testing, became fully operational in June 2022.''SES-17 Ka-Band Satellite is Now Operational'' Via Satellite. 16 June 2022. Accessed 25 August 2022 The satellite operates in conjunction with SES's other geostationary satellites and SES's |
Geostationary Orbit
A geostationary orbit, also referred to as a geosynchronous equatorial orbit''Geostationary orbit'' and ''Geosynchronous (equatorial) orbit'' are used somewhat interchangeably in sources. (GEO), is a circular geosynchronous orbit in altitude above Earth's equator ( in radius from Earth's center) and following the direction of Earth's rotation. An object in such an orbit has an orbital period equal to Earth's rotational period, one sidereal day, and so to ground observers it appears motionless, in a fixed position in the sky. The concept of a geostationary orbit was popularised by the science fiction writer Arthur C. Clarke in the 1940s as a way to revolutionise telecommunications, and the first satellite to be placed in this kind of orbit was launched in 1963. Communications satellites are often placed in a geostationary orbit so that Earth-based satellite antennas do not have to rotate to track them but can be pointed permanently at the position in the sky where the sat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alcan Systems
ALCAN Systems GmbH is a telecommunications company based in Darmstadt, Germany. The company is currently developing low-cost smart antenna systems for fixed, mobile, cellular and satellite-communication. These antennae are flat, thin and able to steer their beams electronically without any moving parts at an extremely affordable price. ALCAN’s technology is based on liquid crystal (LC) based phased-arrays that are capable of operating in the millimeter and microwave bands of the RF spectrum. History ALCAN (Adaptive Liquid Crystal Antenna) Systems’ technology is based on original research initiated at the Institute for Microwave Engineering and Photonics (IMP) at Technische Universität Darmstadt. Professor Rolf Jakob, director of the IMP and later co-founder of ALCAN Systems, started his research on liquid crystal in radio-frequency applications in 1999. He is considered the father of LC RF applications. Onus H. Kara bey joined Jakobe’s research team as a research assis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megabit
The megabit is a multiple of the unit bit for digital information. The prefix mega (symbol M) is defined in the International System of Units (SI) as a multiplier of 106 (1 million), and therefore :1 megabit = = = 1000 kilobits. The megabit has the unit symbol Mbit or Mb. The lowercase 'b' in Mb distinguishes it from MB (for megabyte). The megabit is closely related to the mebibit, a unit multiple derived from the binary prefix mebi (symbol Mi) of the same order of magnitude, which is equal to = , or approximately 5% larger than the megabit. Despite the definitions of these new prefixes for binary-based quantities of storage by international standards organizations, memory semiconductor chips are still marketed using the metric prefix names to designate binary multiples. Using the common byte size of eight bits and the standard decimal definition of megabit and kilobyte, 1 megabit is equal to 125 kilobytes (kB) or approximately 122 kibibytes (KiB). The megab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Contention Ratio
In computer networking, the contention ratio is the ratio of the potential maximum demand to the actual bandwidth. The higher the contention ratio, the greater the number of users that may be trying to use the actual bandwidth at any one time and, therefore, the lower the effective bandwidth offered, especially at peak times.UK OFCOM research report annex on broadban/ref> A ''contended service'' is a service which offers the users of the network a minimum statistically guaranteed contention ratio, while typically offering peaks of usage of up to the maximum bandwidth supplied to the user. Contended services are usually much cheaper to provide than uncontended services, although they only reduce the backbone traffic costs for the users, and do not reduce the costs of providing and maintaining equipment for connecting to the network. Examples by country In the United Kingdom, a Rate Adaptive Digital Subscriber Line ( RADSL) connection used to be marketed with a contention ratio bet ... [...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] |
Phased Array
In antenna theory, a phased array usually means an electronically scanned array, a computer-controlled array of antennas which creates a beam of radio waves that can be electronically steered to point in different directions without moving the antennas. In a simple array antenna, the radio frequency current from the transmitter is fed to multiple individual antenna elements with the proper phase relationship so that the radio waves from the separate elements combine ( superpose) to form beams, to increase power radiated in desired directions and suppress radiation in undesired directions. In a phased array, the power from the transmitter is fed to the radiating elements through devices called ''phase shifters'', controlled by a computer system, which can alter the phase or signal delay electronically, thus steering the beam of radio waves to a different direction. Since the size of an antenna array must extend many wavelengths to achieve the high gain needed for narrow bea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geostationary
A geostationary orbit, also referred to as a geosynchronous equatorial orbit''Geostationary orbit'' and ''Geosynchronous (equatorial) orbit'' are used somewhat interchangeably in sources. (GEO), is a circular geosynchronous orbit in altitude above Earth's equator ( in radius from Earth's center) and following the direction of Earth's rotation. An object in such an orbit has an orbital period equal to Earth's rotational period, one sidereal day, and so to ground observers it appears motionless, in a fixed position in the sky. The concept of a geostationary orbit was popularised by the science fiction writer Arthur C. Clarke in the 1940s as a way to revolutionise telecommunications, and the first satellite to be placed in this kind of orbit was launched in 1963. Communications satellites are often placed in a geostationary orbit so that Earth-based satellite antennas do not have to rotate to track them but can be pointed permanently at the position in the sky where the sate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
