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Early cellular systems
Early cellular systems were analog. They are called first generation mobile systems.
NMT450 Nordic Mobile Telephone 450 (1969) - Finland, Norway, Sweden
•Band 450MHz
•Become available in 1981
•First cellular system in Saudi Arabia (1981)
-NMT450 markets: Europę and Middle East
-NMT450 systems were installed in various countries on different frequencies and different channel spacings. This madę them incompatible.
-NMT900 is basically NMT450 system moved to 900MHz.
AMPS Advanced Mobile Phone Service -Band 800MHz
-AMPS markets: North and South America -Become available in 1983
-AMPS has variants: TACS (Total Access Communication System enhanced AMPS) and JTACS (Japanese version of TACS)
TACS
-Operates at 900MHz frequency rangę -TACS was developed by Motorola -TACS was first used in UK in 1985
Notę:
First cellular network in New York 1976 - max. 12 connection => 500 subscribers.
In the queue there were waiting 3700 people who would like to be a member of this network.
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