Telecommunication
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 (such as postal mail) are excluded from the field.
The transmission media in telecommunication have evolved through numerous
stages of technology, from beacons and other visual signals (such as smoke
signals, semaphore telegraphs, signal flags, and optical heliographs), to electrical
cable and electromagnetic radiation, including light. Such transmission paths are
often divided into communication channels, which afford the advantages of
multiplexing multiple concurrent communication sessions.
Telecommunication
is
often used in its plural form.
Other examples of pre-modern long-distance communication included audio
messages, such as coded drumbeats, lung-blown horns, and loud whistles. 20th-
and 21st-century technologies for long-distance communication usually involve
electrical and electromagnetic technologies, such as telegraph, telephone,
television and teleprinter, networks, radio, microwave transmission, optical fiber,
and communications satellites.
A revolution in wireless communication began in the first decade of the 20th
century with the pioneering developments in radio communications by Guglielmo
Marconi, who won the Nobel Prize in Physics in 1909, and other notable
pioneering inventors and developers in the field of electrical and electronic
telecommunications. These included Charles Wheatstone and Samuel Morse
(inventors of the telegraph), Antonio Meucci and Alexander Graham Bell (some of
the inventors and developers of the telephone, see Invention of the telephone),
Edwin Armstrong and Lee de Forest (inventors of radio), as well as Vladimir K.
Zworykin, John Logie Baird and Philo Farnsworth (some of the inventors of
television).
According to
Article 1.3
of the Radio Regulations (RR), telecommunication is
defined as
« Any transmission, emission or reception of signs, signals, writings,
images and sounds or intelligence of any nature by wire, radio, optical, or other
electromagnetic systems
.» This definition is identical to those contained in the
Annex to the Constitution and Convention of the International Telecommunication
Union (Geneva, 1992).
The early telecommunication networks were created with copper wires as the
physical medium for signal transmission. For many years, these networks were
used for basic phone services, namely voice and telegrams. Since the
mid-1990s, as the internet has grown in popularity, voice has been gradually
supplanted by data. This soon demonstrated the limitations of copper in data
transmission, prompting the development of optics.
computer
A
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