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A digital cellular telephone technology that is based on time-division multiple access; it operates on the 900-megahertz and 1.8-gigahertz bands in Europe, where it is the predominant cellular system, and on the 1.9-gigahertz band in the United States. Derived from global system for mobile communications.



(Global System for Mobile Communications) A digital cellular phone technology that started in Europe. The GSM Association (GSMA) defines the entire cellular system for GSM as well as LTE phones. GSM uses the TDMA air interface, while LTE uses OFDM (see LTE).

In the early 1990s, GSM enabled roaming across European nations for the first time. Eventually more than three billion customers worldwide could phone each other via roaming agreements between the carriers. AT&T and T-Mobile offered GSM service in the U.S., while Rogers Wireless deployed GSM in Canada.

GSM operates in several frequency bands, including 900 MHz and 1.8 GHz in Europe and 850 MHz and 1.9 GHz in the U.S. and Canada. GSM's TDMA technology is based on a circuit-switched system that divides each 200 kHz channel into eight 25 kHz time slots.

The SIM Smart Card
GSM phones use a Subscriber Identity Module (SIM) card that contains user account information. Every GSM phone becomes immediately programmed after inserting the SIM card, thus allowing GSM phones to be easily rented or borrowed. See SIM card.

Text and Data
Text messaging (SMS) and data transfer were built into GSM, and data rates have continually increased over the years. See GPRS, WCDMA, EDGE, HSCSD, GSM Association, GSA, TDMA, CDMA and PCS.

Vive la Cellphone!

When GSM phones were introduced, they were reported to produce a deafening sound for hearing aid wearers and interfere with pacemakers. Swedish hospitals banned them. An Australian newspaper claimed a motorist set off his airbag with one, and most curious, in Paris, they were said to occasionally reset taxi meters to zero.

The SIM Card
The back of a GSM phone opens, and the tiny SIM card is inserted, as in this example from Europe's Amena cellphone service. The bottom view is the card outside the socket showing contact points.

Evolution of 3G Technologies
This chart shows the evolution of carrier technologies throughout the world as they move from standard cellphone services to high-speed data capabilities.
References in periodicals archive ?
Within these countries, GSM uses four different frequencies: 850, 900, 1800 and 1900MHz.
While GSM is much more widely deployed outside the U.
One of the regional health authorities in the Netherlands is trialling the Waleli GSM Doorbell as a way of allowing nurses to respond more quickly to calls from home patients without first having to drive to a central key-holding depot to collect a front door key.
The AdaptaCell([R]), AirSite([R]), iBSS, and RapidCell([TM]) GSM and CoreCell([TM]) CDMA base stations provide wireless operators and integrators with a full suite of radio access solutions.
The outlook for GSM backhaul, particularly in EMEA and Asia-Pacific, is impressive.
GSM user mobility: The use of location areas operation of location updates handover in GSM criteria taken into account for initiating a handover roaming between networks.
Five of the top 10 fastest growing GSM markets are in Asia
The release of this new module is in conjunction with TriQuint's exhibition at the GSM World Congress in Barcelona, Spain, (13th-16th February) where its products will debut (Hall 2, Space H75).
All generally supported features in GSM will also be supported in the GSM 450 band.
The NetPerformer Cellular Backhaul solution supports multiple GSM interfaces, offers superior optimization and WAN flexibility in a single product, which constitute a unique competitive advantage.
With the Digi Connect RG(TM) GSM, we're leveraging this vast experience to make remote wireless networking easy for devices with serial ports.
The efficiency of this PA in GSM mode supports long handset battery life as phones are used mostly for voice communication," said David Pickett, TriQuint's GSM Product Marketing Director.