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2G, or second-generation cellular network technology, marks the transition from analog to digital communication in mobile networks. Defined by the European Telecommunications Standards Institute (ETSI) under the GSM standard, which became the first globally adopted framework for mobile communications, 2G was first commercially launched in 1991 by Radiolinja (now part of Elisa Oyj) in Finland. [1]
Further GSM-850 is also sometimes called GSM-800 because this frequency range was known as the "800 MHz band" (for simplification) when it was first allocated for AMPS in the United States in 1983. In North America GSM-1900 is also referred to as Personal Communications Service (PCS) like any other cellular system operating on the "1900 MHz band".
In addition to radio frequencies used to connect handsets with cellular base stations, other parts of the radio spectrum are used to interconnect base stations and the wired telephone network. Some frequency bands may be vulnerable to interference by existing services in adjacent frequency bands, such as UHF television broadcasting.
Mobile networks based on different standards may use the same frequency range; for example, AMPS, D-AMPS, N-AMPS and IS-95 all use the 800 MHz frequency band. Moreover, one can find both AMPS and IS-95 networks in use on the same frequency in the same area that do not interfere with each other.
GSM networks operate in a number of different carrier frequency ranges (separated into GSM frequency ranges for 2G and UMTS frequency bands for 3G), with most 2G GSM networks operating in the 900 MHz or 1800 MHz bands. Where these bands were already allocated, the 850 MHz and 1900 MHz bands were used instead (for example in Canada and the ...
Good coverage due to low frequencies Very low density Hard No 2G: TDMA and FDMA: GSM: Digital: 1991 Worldwide, all countries except Japan and South Korea SIM card: Some electronics, e.g. amplifiers Good coverage indoors on 850/900 MHz. Repeaters possible. 35 km hard limit. Very low density Hard Yes GPRS Class A 2G: CDMA: IS-95 (CDMA one ...
However, none of them have achieved universal acceptance. Competitors include Xiaomi and Nokia. 6G is expected to offer faster speeds than 5G but with a shorter range. The IEEE recommends the use of frequencies ranging from 100 GHz to 3 THz, as these frequencies are relatively unused and would allow for exploration of new frequency bands. [8]
Typical 2G standards include GSM and IS-95 with extensions via GPRS, EDGE and 1xRTT, providing Internet access to users of originally voice centric 2G networks. Both EDGE and 1xRTT are 3G standards, as defined by the ITU , but are usually marketed as 2.9G due to their comparatively low speeds and high delays when compared to true 3G technologies.