Презентация на английском языке на теме: "История сотовых телефонов"

History of mobile phones

A mobile phone (also called mobile, cellular phone, cell phone, or hand phone) is an electronic device used for full duplex two-way radio telecommunications over a cellular network of base stations known as cell sites. Mobile phones are sure to differ from cordless telephones, which only offer telephone service within limited range through a single base station attached to a fixed landline, for example, within a home or an office.

Radiophones have a long and varied history. It goes back to Reginald Fessenden’s invention and shore to-ship demonstration of radio telephony through the Second World War with military use of radio telephony links and civil services in the 1950s.

Реджинальд Обри Фессенден — канадский и американский изобретатель, хорошо известный своими работами на ранних этапах развития радио.

In 1960 the world’s first partly automatic car phone system, Mobile System A (MTA) was launched in Sweden. MTA phones were composed of vacuum tubes and relays, and had a weight of 40 kg. In 1962 a more modern version called Mobile System В (MTB) was launched.

It was a push-button telephone, which used transistors in order to enhance the telephone’s calling capacity and improve its operational reliability. In 1971 the MTD version was launched, opening for several different brands of equipment and gaining commercial success.

The first commercially automated cellular network (the 1G — first gen­eration) was launched in Japan in 1979. Within five years the network had been expanded to cover the whole population of Japan and became the first nation-wide 1G network. This was followed by the simultaneous launch of the Nordic Mobile Telephone (NMT) system in Denmark, Finland, Norway, and Sweden.

NMT appeared to be the first mobile phone network featuring international roaming. The first network technology on digital 2G (second generation) cellular technology appeared in Finland on the GSM standard. One of the newest 3G technologies to be implemented is mobile telephony communications protocol in the High-Speed Packet Access (HSPA) family. It allows networks based on Universal Mobile Telecommunication System (UMTS) to have higher data transfer speeds and capacity.

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