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The mobile phone
The celular phone has developed a great evolution in the activities that we realised daily, that over the years became a fundamental piece for all of us. Nowadays one says that ourcountry has more than 16 million of celular, that are equivalent to almost one by each person.
At the beginin, this new creation was done only for the voice, but today we can realize that the mobiletechnology can give us other types of services, like audio, video, Internet, camera, etc. That complements much more its use, and even continues with the search of more new features and improvements.Brief History of the mobile phone:
Martin Cooper was the instigator of this new technology. Denominated as “the father of the cellular telephony” putting in use the first radius telephonein 1973 in the United States. Although the first model of cellular is attributed to the Motorola company, was until in 1979 when appears the first commercial sale of mobile telephones, in Japan (Tokyo)by company NTT.
The wireless telephony had a great acceptance thus soon after was begun to saturate the service. This equipment doesn’t show restrictions, can be spoken in any schedule and anyplace.

The possible telephone communication is thanks to the interconnection between mobile and public power stations. This consists in a combination of a network of transmitters-receiversstations, and a series of central telephone offices.

In its operation the mobile telephone contacts with its station bases and as they are moved it is changing the call to the following stationbases.
Generations of the mobile telephony:
First generation (1G): year (1979) was characterized for being strictly to the voice and the quality of very low connections.
Second generation (2G): year(1990) was characterized for being much more sophisticated, and they are the present systems of the cellular telephony.
Third generation (3G): year (2002) approx. Makes possible the wireless access...