|
|
-
This 1G analog system for mobile communications has two major improvements during 1970s, they are:
· Invention of microprocessor
· Digitization of control link between cell phone and cell site.
-
These systems used analogue circuit-switched technology, with FDMA (Frequency Division Multiple Access), and worked mainly in the 800-900 MHz frequency bands.
-
The networks had a low traffic capacity, unreliable handover, poor voice quality, and poor security.
-
Examples of these 1G mobile phone networks are AMPS (Advanced Mobile Phone Service), TACS/ETACS (Total Access Communications System / Extended Total Access Communications System), NMT
450 (Nordic Mobile Telephone System) and NTT (Nippon Telegraph and Telephone
System).
-
Mobile phones were very large at first and were designed for permanent
installation in cars. However later, these bulky units were converted as
transportable phones with the size of a briefcase.
-
The very first truly portable, hand held phone were introduced by
Motorola.
|
|