Dr. Martin Cooper of Motorola, made the first US analogue mobile phone call on a larger prototype model in 1973.
Dr. Martin Cooper
In December 1947, Douglas H. Ring and W. Rae Young, Bell Labs engineers, proposed hexagonal cells for mobile phones. 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 3 directions (see picture at right) into 3 adjacent hexagon cells. 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 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 didn't require any kind of manual control, 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, the young radio engineer Leonid Kupriyanovich in Moscow, USSR, made the experimental model of wearable automatic mobile phone ("radiophone"), called him as LK-1, with base station. LK-1 has 3 kg weight, 20–30 km operating distance, and 20–30 hours of battery life ("Nauka i zhizn", 8, 1957, p. 49, "Yuniy technik", 7, 1957, p. 43-44). Leonid Kupriyanovich patented this mobile phone in 1957 (author's certificate № 115494, 1.11.1957). The base station, in accordance with author's description, could serve several customers. In 1958, Kupriyanovich made the new experimental "pocket" model of mobile phone.

This phone has 0,5 kg weight. To serve more customers, Kupriyanovich proposed the device, named him as correllator. ("Nauka i zhizn", 10, 1958, p.66, "Technika-molodezhi", 2, 1959, 18-19)

In 1958 USSR also started the developing of "Altay" national civil mobile phone service for cars, based on Soviet MRT-1327 standard. The main developers of Altay system were VNIIS (Voronezh Science Research

Institute of Communications)and GSPI (State Specialized Project Institute). In 1963 this service started in Moscow and in 1970 Altay service used in USSR for 30 cities. Last upgraded versions of Altay system still in use in some places of Russia as trunking system.

In 1966, Bulgaria presented the pocket mobile automatic phone RAT-0,5 with base station RATZ-10 (RATC-10) on Interorgtechnika-66 international exhibition. One base station, connected to one telephone wire line, could serve 6 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, 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

Service (AMPS) and allocated frequencies in the 824-894 MHz band. 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.

First generation

On April 3, 1973, Motorola employee Dr. Martin Cooper placed a call to a rival, Dr. Joel S. Engel, head of research at AT&T's Bell Labs, while walking the streets of New York City talking on the first Motorola

DynaTAC prototype in front of reporters. Motorola has a long history of making automotive radio, especially two-way radios for taxicabs and police cruisers.

In 1978, Bell Labs launched a trial of the first commercial cellular network in Chicago using AMPS, but this network was not approved by the FCC until 1982.

The first commercial launch of cellular telecoms was launched by NET in Tokyo Japan in 1979. In 1981 the NMT system was launched in Denmark, Finland, Norway and Sweden.

The first hand held mobile phone in the US market was the Motorola_Dyna 8000X, which received approval in 1983.

Mobile phones began to proliferate through the 1980s with the introduction of "cellular" phones based on cellular networks with multiple base stations located relatively close to each other, and protocols for the automated "handover" between two cells when a phone moved from one cell to the other. At this time analog transmission was in use in all systems. Mobile phones were somewhat larger than current ones, and at first, all were designed for permanent installation in vehicles (hence the term car phone). Soon, some of these bulky units were converted for use as "transportable" phones the size of a briefcase. Motorola

introduced the first truly portable, hand held phone. These systems (NMT, AMPS, TACS, RTMI, C-Net, and Radiocom 2000) later became known as first generation (1G) mobile phones.

Read more here: http://en.wikipedia.org/wiki/History_of_mobile_phones

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