Telecommunication circuit

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A telecommunication circuit is an electrical path in telecommunication used to transmit information. [1]



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]


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

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  1. 1 2 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 )