An IMTS car phone, built by Motorola, from 1964. It weighed 40 pounds, half as much as the original 1940s units.
(Motorola Archives, reproduced with permission from Motorola, Inc.)
História do telefone celular na AmericanHeritage.com – The Cell-Phone Revolution.
“After the telephone was developed in the mid-1870s, and radio at the turn of the century, it was natural to seek ways to combine the two, merging radio’s mobility with the telephone’s person-to-person capability and extensive network. Ship-to-shore radiotelephones were available as early as 1919, and the next decade saw the arrival of two-way radios for police cars, ambulances, and fireboats. These public-safety radios were mobile, but they were limited by the range (usually small) of the transmitter, and they connected only with fellow users, not with every telephone subscriber. Also, like all radio equipment of the day, they were big and clunky; Dick Tracy’s two-way wrist radio existed only in the funny pages.
America’s mobile phone age started on June 17, 1946, in St. Louis. Mobile Telephone Service (MTS), as it was called, had been developed by AT&T using Motorola-made radio equipment, and Southwestern Bell, a subsidiary of AT&T, was the first local provider to offer it. These radiotelephones operated from cars or trucks, as would all mobile phones for the next quartercentury. The Monsanto Chemical Company and a building contractor named Henry Perkinson were the first subscribers. Despite having only six channels (later reduced to three), which resulted in constant busy signals, MTS proved very popular in St. Louis and was quickly rolled out in 25 other major cities. Waiting lists developed wherever it went.
No one in 1946 saw mobile telephony as a mass market. The phones were big, expensive, and complicated to use, and callers had little privacy. Worst of all, only a tiny sliver of bandwidth around 150 MHz was available for the spectrum-hungry service. Still, it was a start. MTS would be modified somewhat over the years, but it was basically the way all mobile phones operated until cellular technology came along in the 1980s. (…)”