Monday, 15 March 2010

Pioneers of the cell phone

In December 1947, Douglas H. Ring and W. Rae Young, Bell Labs engineers, proposed hexagonal cells for mobile phones in vehicles.[2] Philip T. Porter, also of Bell Labs, proposed that the cell towers be at the corners of the hexagons rather than the centers and have directional antennas that would transmit/receive in three directions (see picture at right) into three adjacent hexagon cells.[3][4] The technology did not exist then and the frequencies had not yet been allocated. Cellular technology was undeveloped until the 1960s, when Richard H. Frenkiel and Joel S. Engel of Bell Labs developed the electronics.

Recognizable mobile phones with direct dialing have existed at least since the 1950s. In the 1954 movie Sabrina, the businessman Linus Larrabee (played by Humphrey Bogart) makes a call from the phone in the back of his limousine.

The first person to have a mobile phone in the United Kingdom was reputedly Prince Philip, who had a system fitted into the trunk of his Aston Martin in 1957. The Prince could make phone calls to the Queen while driving, which was thought to be quite amazing at the time. The Duke of Gloucester heard about the mobile phone and tried to obtain one, but the Post Office denied his request. They were prepared to indulge the husband of Her Majesty, but nobody else, as the system used an entire dedicated radio frequency.

The first fully automatic mobile phone system, called MTA (Mobile Telephone system A), was developed by Ericsson and commercially released in Sweden in 1956. This was the first system that did not require any kind of manual control in base stations, but had the disadvantage of a phone weight of 40 kg (90 lb). MTB, an upgraded version with transistors, weighing 9 kg (20 lb), was introduced in 1965 and used DTMF signaling. It had 150 customers in the beginning and 600 when it shut down in 1983.

In 1957 young Soviet radio engineer Leonid Kupriyanovich from Moscow created the portable mobile phone, named after himself as LK-1 or "radiophone".[5] This true mobile phone consisted of a relatively small-sized handset equipped with an antenna and rotary dial, and communicated with a base station. Kupriyanovich's "radiophone" had 3 kilogram of total weight, could operate up to 20 or 30 kilometers, and had 20 or 30 hours of battery lifespan. LK-1 and its layout was depicted in popular Soviet magazines as Nauka i zhizn, 8, 1957, p. 49, Yuniy technik, 7, 1957, p. 43–44. Engineer Kupriyanovich patented his mobile phone in the same year 1957 (author's certificate (USSR Patent) # 115494, 1.11.1957). The base station of LK-1 (called ATR, or Automated Telephone Radiostation) could connect to local telephone network and serve several customers.

In 1958, Kupriyanovich resized his "radiophone" to "pocket" version. The weight of improved "light" handset was about 500 grams.

In 1958 the USSR also began to deploy the "Altay" national civil mobile phone service specially for motorists. [6] The newly-developed mobile telephone system was based on Soviet MRT-1327 standard. The main developers of the Altay system were the Voronezh Science Research Institute of Communications (VNIIS) and the State Specialized Project Institute (GSPI). In 1963 this service started in Moscow, and in 1970 the Altay service already was deployed in 30 cities of the USSR. The last upgraded versions of the Altay system are still in use in some places of Russia as a trunking system.

In 1959 a private telephone company located in Brewster, Kansas, USA, the S&T Telephone Company, (still in Business today) with the use of Motorola Radio Telephone equipment and a private tower facility, offered to the public mobile telephone services in that local area of NW Kansas. This system was a direct dial up service through their local switchboard, and was installed in many private vehicles including grain combines, trucks, and automobiles. For some as yet unknown reason, the system after being placed online and operated for a very brief time period was shut down. The management of the company was immediately changed, and the fully operable system and related equipment was immediately dismantled in early 1960, not to be seen again.

In 1966, Bulgaria presented the pocket mobile automatic phone RAT-0,5 combined with a base station RATZ-10 (RATC-10) on Interorgtechnika-66 international exhibition. One base station, connected to one telephone wire line, could serve up to six customers.

In 1967, each mobile phone had to stay within the cell area serviced by one base station throughout the phone call. This did not provide continuity of automatic telephone service to mobile phones moving through several cell areas. In 1970 Amos E. Joel, Jr., another Bell Labs engineer,[7] invented an automatic "call handoff" system to allow mobile phones to move through several cell areas during a single conversation without loss of conversation.

In December 1971, AT&T submitted a proposal for cellular service to the Federal Communications Commission (FCC). After years of hearings, the FCC approved the proposal in 1982 for Advanced Mobile Phone System (AMPS) and allocated frequencies in the 824–894 MHz band.[8] Analog AMPS was superseded by Digital AMPS in 1990.

One of the first successful public commercial mobile phone networks was the ARP network in Finland, launched in 1971. Posthumously, ARP is sometimes viewed as a zero generation (0G) cellular network, being slightly above previous proprietary and limited coverage networks.

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