April 3, 1973 - Martin Cooper of Motorola invented the
cell phone and provides a public demonstration. He made the call to his rival,
Joel Engel -Bell Labs head of research.
Motorola and AT&T Bell Labs were competing to
develop cellular communications in the sixties and early seventies. Although
AT&T’s Bell Laboratories introduced cellular communications in 1947, Martin
Cooper was the first to incorporate the technology into portable devices. His
experiment began with a base station in New York and the first working
prototype of a cellular telephone, the Motorola Dyna-Tac.
After some initial testing in Washington for the F.C.C., the cellular phone technology was shown to the public in New York.
After some initial testing in Washington for the F.C.C., the cellular phone technology was shown to the public in New York.
The Dyna-Tac weighed roughly 2.5 pounds, included 30
circuit boards and required 10 hours to charge for 35 minutes of talking time.
The technology of modern cell phones started with the
creation of hexagonal cells for mobile phones by D.H. Ring from Bell Labs in
1947, later on another engineer from Bell Labs conceived of cell towers that
would transmit and receive signals in three directions instead of normal bi
directional antennas. By 1967, mobile phone technology was available; however,
the user had to stay within one cell area. In 1970, Amos Edward Joel developed
the call handoff system to facilitate continuity of a phone call from one area
to another without dropping the phone call. In 1971, AT&T submitted a
request to the FCC for cellular service. It took more than 10 years for an
approval and in 1982; the FCC allocated the frequencies of 824-894 MHZ Band to
Advanced Mobile Phone Service (AMPS). From 1982 to 1990, AMPS was an analog
service, Digital AMPS came online as of 1990.
The first mobile phones were installed in vehicles due
to the large battery requirements. The MTA (Mobile Telephone System A)
developed by Eriksson was available in Sweden in 1950′s. Unfortunately, it
weighed over 80 pounds, later versions however weighed around 20 pounds, still
making it ineffective for mobility. In 1983, Motorola unveiled the Motorola
DynaTAC 8000X, the first truly portable cellular phone. It weighed 28 ounces
and was known as the Brick for its shape.