Mobile Phone Handheld Hardware Hardware Rick Rogers John Lombardo O'Reilly Media, Inc. O'Reilly Media Android Application Development, 1st EditionA.1. PrehistoryWhen mobile phones were first invented in the 1940s, they were just
analog radios driven from a car battery. The system was aptly named
Mobile Telephone System (MTS), and it was woefully
inadequate. In spite of the high cost of service, waiting lists to obtain
the service were long because MTS offered only a few channels in any
geography. An "improved" version called IMTS, introduced in the 1960s,
helped some, but was still far short of the demand. The first analog cellular radio mobile phone systems started to
appear in 1969 and the early 1970s—with phones still the size of a
briefcase. The various cellular technologies in North America converged
around the Advanced Mobile Phone Service (AMPS) standard, still analog technology but now based on cellular radios
that could reuse the frequency spectrum and were standardized across
manufacturers. At this time Europe had no less than nine different analog
mobile phone technology standards, one for each major region and country
in the continent.
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