The history focuses on communication devices which connect wirelessly to the public switched telephone network. The transmission of speech by radio has a long and varied history going back to Reginald Fessenden's invention and shore-to-ship demonstration of radio telephony. The first mobile telephones were barely portable compared to today's compact hand-held devices. Along with the process of developing more portable technology, drastic changes have taken place in the networking of wireless communication and the prevalence of its use.
The Second World War made military use of radio telephony links. Hand-held radio transceivers have been available since the 1940s. Mobile telephones for automobiles became available from some telephone companies in the 1940s. Early devices were bulky and consumed high power and the network supported only a few simultaneous conversations. Modern cellular networks allow automatic and pervasive use of mobile phones for voice and data communications.
In the United States, engineers from Bell Labs began work on a system to allow mobile users to place and receive telephone calls from automobiles, leading to the inauguration of mobile service on 17 June 1946 in St. Louis, Missouri. Shortly after, AT&T offered Mobile Telephone Service. A wide range of mostly incompatible mobile telephone services offered limited coverage area and only a few available channels in urban areas. The introduction of cellular technology, which allowed re-use of frequencies many times in small adjacent areas covered by relatively low powered transmitters, made widespread adoption of mobile telephones economically feasible.In the USSR, Leonid Kupriyanovich, engineer from Moscow, in 1957-1961 developed and presented a number of experimental models of handheld mobile phone. The weight of one model, presented in 1961, was only 70 g and could fit on a palm.[verification needed] However in the USSR the decision at first to develop the system of automobile "Altai" phone was made ("Nauka i zhizn" magazine, 8, 1957 and 10, 1958, "Technika-molodezhi" magazine, 2, 1959, "Za rulem" magazine, 12, 1957, "Yuny technik" magazine, 7, 1957, 2, 1958 and 9, 1996, "Orlovskaya pravda" newspaper, 12, 1961).
In 1965, Bulgarian company "Radioelektronika" presented on Inforga-65 interrnational exhibition in Moscow the mobile automatic phone combined with a base station. Solutions of this phone were based on a system developed by Leonid Kupriyanovich. One base station, connected to one telephone wire line, could serve up to 15 customers. ("Nauka i zhizn" magazine, 8, 1965).
The advances in mobile telephony can be traced in successive generations from the early "0G" services like MTS and its successor Improved Mobile Telephone Service, to first generation (1G) analog cellular network, second generation (2G) digital cellular networks, third generation (3G) broadband data services to the current state of the art, fourth generation (4G) native-IP networks. Motorola was the first company to produce a handheld mobile phone. On 3 April 1973 Martin Cooper, a Motorola engineer and executive, made the first mobile telephone call from handheld subscriber equipment in front of reporters, placing a call to Dr. Joel S. Engel of Bell Labs.[5][6] The prototype handheld phone used by Dr. Martin Cooper weighed 1.1 kg and measured 23 cm long, 13 cm deep and 4.45 cm wide. The prototype offered a talk time of just 30 minutes and took 10 hours to re-charge.[7] Cooper has stated his vision for the handheld device was inspired by Captain James T. Kirk using his Communicator on the television show Star Trek.[8]
John F. Mitchell,[9][10][11] Motorola's chief of portable communication products and Martin Cooper's boss in 1973, played a key role in advancing the development of handheld mobile telephone equipment. Mitchell successfully pushed Motorola to develop wireless communication products that would be small enough to use anywhere and participated in the design of the cellular phone.[12][13]