Cellular telephony – Part I I go to divide the article in parts because I want to describe of detailed form all the details on the Cellular Telephone. In 1947 the MTS, System of Mobile Telephony was created (the things in English costumam to be behind for front), aiming at to take care of the people who were in transit and had the necessity of if communicating. This system was improved and in 1964 the IMTS, Implemented System of Mobile Telephony, a perfectioning was created on the basis of the MTS. Together these two can be considered the precursors of the modern Cellular Telephony. In middle of the decade of 70 the technology if became available to leave the viable service in the economic point of view, although the principles and basic ideas to have appeared in 1940 in the laboratories Bell (Bell, the father of the telephone remembers the Graham). At the beginning of 1970 the first experimental system of Mobile Telephony with 2.000 customers in the city of Chicago in &#039 was placed in functioning; ' States' ' ; of new the laboratories Bell they were in the area.

A little later as an experimental system it entered in functioning in Washington. In 1975 the FCC, Federal Commission of Communication, brought the competition to the field of the mobile telephony opening 40MHz of band of 800MHz for any qualified carrier. However, in October of 1983 the system was only activated commercially in Chicago, two years before Sweden had inaugurated commercially the first Mobile Cellular Service of the world, with this the United States had lost ' ' primognitura' ' in the commercial field of the Mobile Telephony. From there in ahead the system if it spread over the whole world and with the technological evolution each accessible time became. Coming back in the time The MTS the Mobile System of Telephony (servant in 1947, remembers), operated in Simplex canal, what it wants to say that was not possible to speak and to listen simultaneously, the information followed in an only direction of each time.