Telecommunication circuit

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A telecommunication circuit is a path in a telecommunications network used to transmit information.

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Definitions

A telecommunication circuit may be defined as follows:[ citation needed ]

In operational terms, a telecommunication circuit may be capable of transmitting information in only one direction (simplex circuit), or it may be bi-directional (duplex circuit). Bi-directional circuits may support half-duplex operation, when only one end of the channel transmits at any one time, or they may support full-duplex operation, when independent simultaneous transmission occurs in both directions. [1]

Applications

Originally, telecommunication circuits transmitted analog information. Radio stations used them as studio transmitter links (STLs) or as remote pickup unit (RPU) for sound reproduction, sometimes as a backup to other means. Later lines were digital, used in pair-gain applications, such as carrier systems, or in enterprise data networks.

A leased line, private circuit, or dedicated circuit, is a circuit that is dedicated to only one use and is typically not switched at a central office. The opposite is a switched circuit, which can be connected to different paths in a switching center or telephone exchange. Plain old telephone service (POTS) and ISDN telephone lines are switched circuits.

On certain types of telecommunication circuits, a virtual circuit may be created, while sharing the physical circuit.

See also

Related Research Articles

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Repeater

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A transmission medium is something that can mediate the propagation of signals for the purposes of telecommunication.

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Microwave transmission

Microwave transmission is the transmission of information by microwave radio waves. Although an experimental 40-mile (64 km) microwave telecommunication link across the English Channel was demonstrated in 1931, the development of radar in World War II provided the technology for practical exploitation of microwave communication. In the 1950s, large transcontinental microwave relay networks, consisting of chains of repeater stations linked by line-of-sight beams of microwaves were built in Europe and America to relay long distance telephone traffic and television programs between cities. Communication satellites which transferred data between ground stations by microwaves took over much long distance traffic in the 1960s. In recent years, there has been an explosive increase in use of the microwave spectrum by new telecommunication technologies such as wireless networks, and direct-broadcast satellites which broadcast television and radio directly into consumers' homes.

Telecommunications engineering Engineering science that deals with the recording, transmission, processing and storage of messages

Telecommunications Engineering is an engineering discipline centered on electrical and computer engineering which seeks to support and enhance telecommunication systems. The work ranges from basic circuit design to strategic mass developments. A telecommunication engineer is responsible for designing and overseeing the installation of telecommunications equipment and facilities, such as complex electronic switching systems, and other plain old telephone service facilities, optical fiber cabling, IP networks, and microwave transmission systems. Telecommunications engineering also overlaps with broadcast engineering.

Telecommunication Transmission of information between locations using electromagnetic technology

Telecommunication is the transmission of information by various types of technologies over wire, radio, optical or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that feasible with the human voice, but with a similar scale of expediency; thus, slow systems are excluded from the field.

References

  1. Freeman, Roger L. (1999). Fundamentals of Telecommunications . John Wiley & Sons, Inc. ISBN   0471296996.

Further reading

PD-icon.svg This article incorporates  public domain material from the General Services Administration document: "Federal Standard 1037C".(in support of MIL-STD-188)