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28-652: The largest nodes are the Institute for Computational Cosmology in the UK and the Max Planck Institute for Astrophysics in Germany. Other nodes exist in the UK, Netherlands, Canada, USA and Japan. The science goals are to carry out state-of-the-art cosmological simulations with research areas in: This N-body simulation used more than 10 billion particles to trace the evolution of the matter distribution in

56-417: A CB shack . In the context of external land surveying, a base station is a GPS receiver at an accurately-known fixed location which is used to derive correction information for nearby portable GPS receivers. This correction data allows propagation and other effects to be corrected out of the position data obtained by the mobile stations, which gives greatly increased location precision and accuracy over

84-506: A DS-1 , or radio links. The consoles multiplex transmit commands onto remote control circuits. Some system configurations require duplex, or four wire, audio paths from the base station to the console. Others require only a two-wire or half duplex link. Interference could be defined as receiving any signal other than from a radio in your own system. To avoid interference from users on the same channel, or interference from nearby strong signals on another channel, professional base stations use

112-463: A node ( Latin : nodus , ‘knot’) is either a redistribution point or a communication endpoint . A physical network node is an electronic device that is attached to a network, and is capable of creating, receiving, or transmitting information over a communication channel . In data communication, a physical network node may either be data communication equipment (such as a modem , hub , bridge or switch ) or data terminal equipment (such as

140-453: A peer-to-peer or overlay network , nodes that actively route data for the other networked devices as well as themselves are called supernodes . Distributed systems may sometimes use virtual nodes so that the system is not oblivious to the heterogeneity of the nodes. This issue is addressed with special algorithms, like consistent hashing , as it is the case in Amazon's Dynamo . Within

168-419: A " land station in the land mobile service ." The term is used in the context of mobile telephony , wireless computer networking and other wireless communications and in land surveying . In surveying, it is a GPS receiver at a known position, while in wireless communications it is a transceiver connecting a number of other devices to one another and/or to a wider area. In mobile telephony, it provides

196-480: A broader context and is generally associated with a fiber optic node. This can be defined as those homes or businesses within a specific geographic area that are served from a common fiber optic receiver . A fiber optic node is generally described in terms of the number of "homes passed" that are served by that specific fiber node. In a distributed system network, the nodes are clients , servers or peers . A peer may sometimes serve as client, sometimes server. In

224-659: A combination of: Base stations are sometimes called control or fixed stations in US Federal Communications Commission licensing. These terms are defined in regulations inside Part 90 of the commissions regulations. In US licensing jargon, types of base stations include: In amateur radio , a base station also communicates with mobile rigs but for hobby or family communications. Amateur systems sometimes serve as dispatch radio systems during disasters, search and rescue mobilizations, or other emergencies. An Australian UHF CB base station

252-486: A cubic region of the Universe over 2 billion light-years on a side. The first results that were published in 2005 in an issue of Nature , shows how comparing such simulated data to large observational surveys can improve the understanding of the physical processes underlying the buildup of real galaxies and black holes. As of December 2023, the members are: Node (networking) In telecommunications networks ,

280-415: A digital telephone handset, a printer or a host computer ). A passive distribution point such as a distribution frame or patch panel is not a node. In data communication, a physical network node may either be data communication equipment (DCE) such as a modem , hub , bridge or switch ; or data terminal equipment (DTE) such as a digital telephone handset, a printer or a host computer . If

308-438: A fixed location and used to communicate as part of one of the following: Base stations use RF power amplifiers ( radio-frequency power amplifiers) to transmit and receive signals. The most common RF power amplifiers are metal–oxide–semiconductor field-effect transistors (MOSFETs), particularly LDMOS ( power MOSFET ) RF amplifiers. RF LDMOS amplifiers replaced RF bipolar transistor amplifiers in most base stations during

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336-422: A network is a local area network (LAN) or wide area network (WAN), every LAN or WAN node that participates on the data link layer must have a network address , typically one for each network interface controller it possesses. Examples are computers, a DSL modem with Ethernet interface and wireless access point . Equipment, such as an Ethernet hub or modem with serial interface , that operates only below

364-550: A primary selected channel is routed to the select speaker and to a headset. Each channel has a busy light which flashes when someone talks on the associated channel. Base stations can be local controlled or remote controlled. Local controlled base stations are operated by front panel controls on the base station cabinet. Remote control base stations can be operated over tone- or DC-remote circuits. The dispatch point console and remote base station are connected by leased private line telephone circuits, (sometimes called RTO circuit s),

392-551: A properly designed dispatch center with several staff members, this allows each dispatcher to communicate simultaneously, independently of one another, on a different channel as necessary. For example, a taxi company dispatch center may have one base station on a high-rise building in Boston and another on a different channel in Providence . Each taxi dispatcher could communicate with taxis in either Boston or Providence by selecting

420-407: A vast computer network, the individual computers on the periphery of the network, those that do not also connect other networks, and those that often connect transiently to one or more clouds are called end nodes. Typically, within the cloud computing construct, the individual user or customer computer that connects into one well-managed cloud is called an end node. Since these computers are a part of

448-434: Is another example of part of a system used for hobby or family communications. Wireless telephone differ from two-way radios in that: A wireless telephone base station communicates with a mobile or hand-held phone. For example, in a wireless telephone system, the signals from one or more mobile telephones in an area are received at a nearby base station, which then connects the call to the land-line network. Other equipment

476-471: Is involved depending on the system architecture. Mobile telephone provider networks, such as European GSM networks, may involve carrier , microwave radio , and switching facilities to connect the call. In the case of a portable phone such as a US cordless phone, the connection is directly connected to a wired land line. While low levels of radio-frequency power are usually considered to have negligible effects on health, national and local regulations restrict

504-430: Is no convincing scientific evidence that the weak RF signals from base stations and wireless networks cause adverse health effects." The consensus of the scientific community is that the power from these mobile phone base station antennas is too low to produce health hazards as long as people are kept away from direct access to the antennas. However, current international exposure guidelines ( ICNIRP ) are based largely on

532-415: The 1990s, leading to the wireless revolution . In professional two-way radio systems, a base station is used to maintain contact with a dispatch fleet of hand-held or mobile radios, and/or to activate one-way paging receivers. The base station is one end of a communications link. The other end is a movable vehicle-mounted radio or walkie-talkie. Examples of base station uses in two-way radio include

560-514: The connection between mobile phones and the wider telephone network . In a computer network , it is a transceiver acting as a switch for computers in the network, possibly connecting them to a/another local area network and/or the Internet . In traditional wireless communications, it can refer to the hub of a dispatch fleet such as a taxi or delivery fleet, the base of a TETRA network as used by government and emergency services or

588-560: The data link layer does not require a network address. If the network in question is the Internet or an intranet , many physical network nodes are host computers, also known as Internet nodes , identified by an IP address , and all hosts are physical network nodes. However, some data-link-layer devices such as switches, bridges and wireless access points do not have an IP host address (except sometimes for administrative purposes), and are not considered to be Internet nodes or hosts, but are considered physical network nodes and LAN nodes. In

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616-400: The design of base stations to limit exposure to electromagnetic fields . Technical measures to limit exposure include restricting the radio frequency power emitted by the station, elevating the antenna above ground level, changes to the antenna pattern, and barriers to foot or road traffic. For typical base stations, significant electromagnetic energy is only emitted at the antenna, not along

644-415: The dispatch of tow trucks and taxicabs . Professional base station radios are often one channel. In lightly used base stations, a multi-channel unit may be employed. In heavily used systems, the capability for additional channels, where needed, is accomplished by installing an additional base station for each channel. Each base station appears as a single channel on the dispatch center control console. In

672-531: The fixed telephone network, a node may be a public or private telephone exchange , a remote concentrator or a computer providing some intelligent network service . In cellular communication, switching points and databases such as the base station controller , home location register , gateway GPRS Support Node (GGSN) and serving GPRS support node (SGSN) are examples of nodes. Cellular network base stations are not considered to be nodes in this context. In cable television systems (CATV), this term has assumed

700-495: The length of the antenna tower. Because mobile phones and their base stations are two-way radios, they produce radio-frequency ( RF ) radiation in order to communicate, exposing people near them to RF radiation giving concerns about mobile phone radiation and health . Hand-held mobile telephones are relatively low power so the RF radiation exposures from them are generally low. The World Health Organization has concluded that "there

728-503: The network yet unmanaged by the cloud's host, they present significant risks to the entire cloud. This is called the end node problem . There are several means to remedy this problem but all require instilling trust in the end node computer. Base station Base station (or base radio station ) is – according to the International Telecommunication Union 's (ITU) Radio Regulations (RR) –

756-435: The respective base station on his or her console. In dispatching centers it is common for eight or more radio base stations to be connected to a single dispatching console. Dispatching personnel can tell which channel a message is being received on by a combination of local protocol, unit identifiers, volume settings, and busy indicator lights. A typical console has two speakers identified as select and unselect . Audio from

784-444: The results obtained by uncorrected GPS receivers. In the area of wireless computer networking, a base station is a radio receiver/transmitter that serves as the hub of the local wireless network, and may also be the gateway between a wired network and the wireless network. It typically consists of a low-power transmitter and wireless router . In radio communications, a base station is a wireless communications station installed at

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