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AMPS

Advanced Mobile Phone System. Developed by Bell Labs in the 1970s and first used commercially in the United States in 1983. It operates in the 800 MHz band and is currently the world's largest cellular standard.

C-450

Installed in South Africa during the 1980's. Now known as Motorphone and run by Vodacom.

C-Nezt

Cellular technology found mainly in Germany. It operates at 450 MHz.

N-AMPS

Narrowband Advanced Mobile Phone System. Developed by Motorola as an interim technology between analogue and digital. It has some three times greater capacity than AMPS and operates in the 800 MHz range.

NMT450

Nordic Mobile Telephones/450. Developed specially by Ericsson and Nokia to service the rugged terrain that characterises the Nordic countries.Operates at 450 Mhz.

NMT900

Nordic Mobile Telephones/900. The 900 Mhz upgrade to NMT 450 developed by the Nordic countries to accommodate higher capacities and handheld portables.

NTT

Nippon Telegraph and Telephone. The old Japanese analogue standard. A high-capacity version is called HICAP.

TACS

Total Access Communications System. Developed by Motorola. and is similar to AMPS. It was first used in the United Kingdom in 1985, although in Japan it is called JTAC. It operates in the 900 MHz frequency range.

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Digital Cellular Networks. .

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CDMA

Code Division Multiple Access. Developed by Qualcomm Inc. and is characterised by high capacity and small cell radius. It was adopted by the Telecommunications Industry Association (TIA) in 1993. The first CDMA-based networks are now operational.

D-AMPS

Digital AMPS. An upgrade to the analogue AMPs. A AMPS/D-AMPS infrastructure can support use of either analogue AMPS phone or digital D-AMPS phones. This was because the Federal Communications Commission mandated only that digital cellular in the U.S. must act in a dual-mode capacity with analogue. Both operate in the 800 MHz band.

DCS 1800

Digital Cordless Standard. GSM operated in the 1800 MHz range. It is a different version of GSM, and (900 MHz) GSM phones cannot be used on DCS 1800 networks.

GSM

Global System for Mobile Communications. The first European digital standard, developed to establish cellular compatibility throughout Europe. It's success has spread to all parts of the world and over 80 GSM networks are now operational. It operates at 900 MHz.

PCS

Personal Communications Service. The American version of GSM, but GSM phones cannot be used on PCS networks. It operates in the 1,900 MHz range.

PHS

Personal Handy System. A Japanese-centric system that offers high speed data services and superb voice clarity.

TDMA

Time Division Multiple Access. The first U.S. digital standard to be developed. It was adopted by the TIA in 1992. The first TDMA commercial system began in 1993.

 

Zdroje: www.option.com

 



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