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Advanced Mobile Phone System (AMPS) is an analog mobile cell phone system standard developed by Bell Labs, and officially introduced in the Americas on October 13, 1983,〔(Private Line ).〕〔(MilestonesPast ).〕 Israel in 1986, Australia in 1987, and Pakistan in 1990. It was the primary analog mobile phone system in North America (and other locales) through the 1980s and into the 2000s. As of February 18, 2008, carriers in the United States were no longer required to support AMPS and companies such as AT&T and Verizon have discontinued this service permanently. AMPS was discontinued in Australia in September 2000 and in Pakistan by October 2004.〔〔http://www.pta.gov.pk/index.php?cur_t=vtext&option=com_content&id=237&scid=146&Itemid=1〕 == History == (詳細はBell Labs (which first proposed the idea of a cellular system in 1947 and continued to petition the FCC for channels through the 1950s and 1960s) and with research conducted at Motorola. In 1960, John F. Mitchell, an electrical engineer who had graduated from the Illinois Institute of Technology, became Motorola's chief engineer for its mobile-communication products. Mitchell oversaw the development and marketing of the first pager to use transistors. Motorola had long produced mobile telephones for automobiles, but these large and heavy models consumed too much power to allow their use without the automobile's engine running. Mitchell's team, which included the gifted Dr. Martin Cooper, developed portable cellular telephony, and Mitchell was among the Motorola employees granted a patent for this work in 1973; the first call on the prototype connected, reportedly, to a wrong number.〔 Motorola Executive Helped Spur Cellular Revolution, Oversaw Ill-fated Iridium Project, Wall Street Journal, Remembrances, June 20–21, 2009, p. A10 〕〔 〕 While Motorola was developing a cellular phone, from 1968-1983 Bell Labs worked out a system called Advanced Mobile Phone System (AMPS), which became the first cellular network standard in the U.S. Motorola and others designed and built the cellular phones for this and other cellular systems. Martin Cooper, a former general manager for the systems division at Motorola, led a team that produced the DynaTAC8000x, the first commercially available cellular phone small enough to be easily carried, and made the first phone call from it, and later introduced the so-called Bag Phone. In 1992 the first smartphone, called IBM Simon, used AMPS. Frank Canova led its design at IBM and it was demonstrated that year at the COMDEX computer-industry trade-show. A refined version of the product was marketed to consumers in 1994 by BellSouth under the name Simon Personal Communicator. The Simon was the first device that can be properly referred to as a "smartphone", even though that term was not yet coined. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Advanced Mobile Phone System」の詳細全文を読む スポンサード リンク
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