The telecommunications (the Greek prefix, "distance" and the Latin so for us it means something like "distance communication") is a technique of transmitting a message from one point to another, usually typical additional attribute of being bi . The term 'telecommunications covers all forms of distance communication, including radio , telegraph, television , telephony, transmission of data and interconnection of computers in the link level. The World Telecommunication Day is celebrated on May 17 . Telecommunication is any transmission, emission or reception of signs, signals, data, images, voice, sounds or information of any nature which is carried through cables, radio, optical, physical or other electromagnetic systems
The mathematical basis on which to develop telecommunications was developed by English physicist James Clerk Maxwell . Maxwell, in the preface to his book Treatise on Electricity and Magnetism ( 1873) stated that their main task was to justify mathematically described physical concepts so far so only qualitative, as the laws of electromagnetic induction and fields strength, set by Michael Faraday . To this end, he introduced the concept of electromagnetic wave , allowing a proper mathematical description of the interaction between electricity and magnetism by his famous equations that describe and quantify force fields. Maxwell predicted that waves could propagate through free space using electric shocks, a fact corroborated Heinrich Hertz in 1887 , eight years after Maxwell's death, and subsequently, was the beginning of the era of rapid communication distance. Hertz developed the first radio transmitter generating radio frequencies between 31 MHz and 1.25 GHz
The elements of a telecommunication system are a transmitter , a line or transmission medium and possibly imposed by the medium, a channel and finally a receiver . The transmitter is the device that transforms or encodes messages on a physical phenomenon, the signal. The transmission medium, by its physical nature, it is possible to modify or degrade the signal on its way from the transmitter to the receiver due to noise, interference or distortion of the channel itself. Therefore, the recipient must have a decoding mechanism capable of recovering the message within certain limits of signal degradation. In some cases, the final receiver is the ear or the human eye (or in some extreme cases other sense organs) and message retrieval is done by the mind. The Telecommunication can be point to point , point to multipoint or broadcasting, which is a particular form of point-to-multipoint works only from the transmitter to the receivers, being its most popular broadcasters.
The role of engineers telecommunications is to analyze the physical properties of the line or means of communication and the statistical properties of the message in order to design mechanisms for encoding and decoding more appropriate. When systems are designed to communicate through bodies human sensory (mainly vision and hearing) should be taken into account physiological and psychological characteristics of human perception. This has important economic implications and the engineer will investigate that defects can be tolerated in the signal without unduly affecting vision or hearing, based on concepts such as limit frequency detectable by human sensory organs.
Possible imperfections in a communication channel are: impulsive noise, Johnson-Nyquist noise (also known as thermal noise), propagation time , channel transfer function nonlinear signal sudden drops (notches ), limitations in bandwidth and signal reflections (echoes ). Many modern telecommunication systems get advantage of some of these imperfections to ultimately improve the quality of transmission channel.
Modern communication systems make extensive use of temporal synchronization. Up the recent emergence of the use of IP telephony, most communication systems were synchronized to atomic clocks or secondary clocks synchronized to atomic time international obtained in most cases via GPS .
no longer need to establish physical links between two points to transmit information from one point to another. The events in one place, occur at the same time worldwide. We are entering a new kind of society where information is king. Knowledge is power, and know something is all that is needed. In Europe, the Information Society was created in response to the European Community the growth of high-speed networks in the United States and its technological superiority. [Quoted
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