Mobile telephony is the provision of telephone services to mobile phones rather than fixed-location phones (landline phones). Telephony is supposed to specifically point to a voice-only service or connection, though sometimes the line may blur.
Modern mobile phones connect to a terrestrial cellular network of base stations (cell sites), whereas satellite phones connect to orbiting satellites. Both networks are interconnected to the public switched telephone network (PSTN) to allow any phone in the world to be dialed.
In 2010 there were estimated to be five billion mobile cellular subscriptions in the world.
History of mobile phones and History of the prepaid mobile phone
According to internal memos, American Telephone & Telegraph discussed developing a wireless phone in 1915, but were afraid that deployment of the technology could undermine its monopoly on wired service in the U.S.
Public mobile phone systems were first introduced in the years after the Second World War and made use of technology developed before and during the conflict. The first system opened in St. Louis, Missouri, United States in 1946 whilst other countries followed in the succeeding decades. The UK introduced its 'System 1' manual radiotelephone service as the South Lancashire Radiophone Service in 1958. Calls were made via an operator using handsets identical to ordinary phone handsets. The phone itself was a large box located in the boot (trunk) of the vehicle containing valves and other early electronic components. Although an uprated manual service ('System 3') was extended to cover most of the UK, automation did not arrive until 1981 with 'System 4'. Although this non-cellular service, based on German B-Netz technology, was expanded rapidly throughout the UK between 1982 and 1985 and continued in operation for several years before finally closing in Scotland, it was overtaken by the introduction in January 1985 of two cellular systems - the British Telecom/Securicor 'Cellnet' service and the Racal/Millicom/Barclays 'Vodafone' (from voice + data + phone) service.
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A mobile phone (or cellphone) is a portable telephone that can make and receive calls over a radio frequency link while the user is moving within a telephone service area, as opposed to a fixed-location phone (landline phone). The radio frequency link establishes a connection to the switching systems of a mobile phone operator, which provides access to the public switched telephone network (PSTN). Modern mobile telephone services use a cellular network architecture and therefore mobile telephones are called cellphones (or "cell phones") in North America.
Roaming is a wireless telecommunication term typically used with mobile devices, such as mobile phones. It refers to a mobile phone being used outside the range of its native network and connecting to another available cell network. In more technical terms, roaming refers to the ability for a cellular customer to automatically make and receive voice calls, send and receive data, or access other services, including home data services, when travelling outside the geographical coverage area of the home network, by means of using a visited network.
Telia Company AB is a Swedish multinational telecommunications company and mobile network operator present in Sweden, Finland, Norway, Denmark, Estonia, Latvia and Lithuania. Telia also owns TV4 Media which includes TV4 in Sweden, MTV Oy in Finland, and C More Entertainment after acquiring them in 2019. The company is headquartered in Solna and its stock is traded on the Stockholm Stock Exchange and on the Helsinki Stock Exchange.
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