A mobile phone (also called cellphone or handphone as well as wireless phone, cell phone, cellular phone, cellular telephone or cell telephone) is a long-range, electronic device used for mobile voice or data communication over a network of specialized base stations known as cell sites. In addition to the standard voice function of a mobile phone, telephone, current mobile phones may support many additional services, and accessories, such as SMS for text messaging, email, packet switching for access to the Internet, gaming, Bluetooth, infrared, camera with video recorder and MMS for sending and receiving photos and video, MP3 player, radio and GPS. Most current mobile phones connect to a cellular network of base stations (cell sites), which is in turn interconnected to the public switched telephone network (PSTN) (the exception is satellite phones).
In 2008 there were 4,100 million mobile cellular subscriptions in the world.A mobile phone proper typically has a telephone keypad, more advanced devices have a separate key for each letter. Some mobile phones have a touchscreen.
In 2008 there were 4,100 million mobile cellular subscriptions in the world.A mobile phone proper typically has a telephone keypad, more advanced devices have a separate key for each letter. Some mobile phones have a touchscreen.
History
In 1908, U.S. Patent 887,357 for a wireless telephone was issued in to Nathan B. Stubblefield of Murray, Kentucky. He applied this patent to "cave radio" telephones and not directly to cellular telephony as the term is currently understood. Cells for mobile phone base stations were invented in 1947 by Bell Labs engineers at AT&T and further developed by Bell Labs during the 1960s. Radiophones have a long and varied history going 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, while hand-held cellular radio devices have been available since 1973. A patent for the first wireless phone as we know today was issued in US Patent Number 3,449,750 to George Sweigert of Euclid, Ohio on June 10, 1969.
In 1945, the zero generation (0G) of mobile telephones was introduced. 0G mobile phones, such as Mobile Telephone Service, were not cellular, and so did not feature "handover" from one base station to the next and reuse of radio frequency channels.[citation needed] Like other technologies of the time, it involved a single, powerful base station covering a wide area, and each telephone would effectively monopolize a channel over that whole area while in use. The concepts of frequency reuse and handoff as well as a number of other concepts that formed the basis of modern cell phone technology are first described in U.S. Patent 4,152,647 , issued May 1, 1979 to Charles A. Gladden and Martin H. Parelman, both of Las Vegas, Nevada and assigned by them to the United States Government.
This is the first embodiment of all the concepts that formed the basis of the next major step in mobile telephony, the Analog cellular telephone. Concepts covered in this patent (cited in at least 34 other patents) also were later extended to several satellite communication systems. Later updating of the cellular system to a digital system credits this patent.
Martin Cooper, a Motorola researcher and executive is widely considered to be the inventor of the first practical mobile phone for handheld use in a non-vehicle setting. Cooper is the inventor named on "Radio telephone system" filed on October 17, 1973 with the US Patent Office and later issued as US Patent 3,906,166.Using a modern, if somewhat heavy portable handset, Cooper made the first call on a handheld mobile phone on April 3, 1973 to a rival, Dr. Joel S. Engel of Bell Labs.
In 1908, U.S. Patent 887,357 for a wireless telephone was issued in to Nathan B. Stubblefield of Murray, Kentucky. He applied this patent to "cave radio" telephones and not directly to cellular telephony as the term is currently understood. Cells for mobile phone base stations were invented in 1947 by Bell Labs engineers at AT&T and further developed by Bell Labs during the 1960s. Radiophones have a long and varied history going 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, while hand-held cellular radio devices have been available since 1973. A patent for the first wireless phone as we know today was issued in US Patent Number 3,449,750 to George Sweigert of Euclid, Ohio on June 10, 1969.
In 1945, the zero generation (0G) of mobile telephones was introduced. 0G mobile phones, such as Mobile Telephone Service, were not cellular, and so did not feature "handover" from one base station to the next and reuse of radio frequency channels.[citation needed] Like other technologies of the time, it involved a single, powerful base station covering a wide area, and each telephone would effectively monopolize a channel over that whole area while in use. The concepts of frequency reuse and handoff as well as a number of other concepts that formed the basis of modern cell phone technology are first described in U.S. Patent 4,152,647 , issued May 1, 1979 to Charles A. Gladden and Martin H. Parelman, both of Las Vegas, Nevada and assigned by them to the United States Government.
This is the first embodiment of all the concepts that formed the basis of the next major step in mobile telephony, the Analog cellular telephone. Concepts covered in this patent (cited in at least 34 other patents) also were later extended to several satellite communication systems. Later updating of the cellular system to a digital system credits this patent.
Martin Cooper, a Motorola researcher and executive is widely considered to be the inventor of the first practical mobile phone for handheld use in a non-vehicle setting. Cooper is the inventor named on "Radio telephone system" filed on October 17, 1973 with the US Patent Office and later issued as US Patent 3,906,166.Using a modern, if somewhat heavy portable handset, Cooper made the first call on a handheld mobile phone on April 3, 1973 to a rival, Dr. Joel S. Engel of Bell Labs.
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