Editing 2G (section)

== Evolution of GSM 2G ==
[[File:Cellular network standards and generation timeline.svg|thumb|upright=1.4|Cellular network standards and generation timeline. (Large titles on the colored area refer to the lines to their right.]]

=== 2.5G (GPRS) ===
{{Main|GPRS}}
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2.5G ("second-and-a-half generation") refers to 2G systems that incorporate a [[Packet switching|packet-switched]] domain alongside the existing [[Circuit switching|circuit-switched]] domain, most commonly implemented through General Packet Radio Service ([[General Packet Radio Service|GPRS]]).<ref>{{cite web |url=https://www.igi-global.com/dictionary/security-mobile-systems/26010 |title=What is Second and a Half Generation (2.5G) |website=IGI Global |access-date=2019-10-06 |archive-date=2019-10-06 |archive-url=https://web.archive.org/web/20191006162125/https://www.igi-global.com/dictionary/security-mobile-systems/26010 |url-status=live}}</ref> GPRS enables packet-based data transmission by dynamically allocating multiple timeslots to users, improving network efficiency. However, this does not inherently provide faster speeds, as similar techniques, such as timeslot bundling, are also employed in circuit-switched data services like High-Speed Circuit-Switched Data ([[HSCSD]]). Within GPRS-enabled 2G systems, the theoretical maximum [[transfer rate]] is 40 kbit/s (5 kB/s).<ref name=":1">{{cite web |url=https://www.3gpp.org/technologies/keywords-acronyms/102-gprs-edge |title=GPRS & EDGE |website=3gpp.org |access-date=2019-08-17 |archive-date=2020-04-17 |archive-url=https://web.archive.org/web/20200417193611/https://www.3gpp.org/technologies/keywords-acronyms/102-gprs-edge |url-status=live}}</ref>
=== 2.75G (EDGE) ===
{{Main|EDGE (telecommunication)}}
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2.75G refers to the evolution of GPRS networks into [[Enhanced Data rates for GSM Evolution|EDGE]] (Enhanced Data Rates for GSM Evolution) networks, achieved through the introduction of 8PSK (8 Phase Shift Keying) encoding. While the symbol rate remained constant at 270.833 samples per second, the use of 8PSK allowed each symbol to carry three bits instead of one, significantly increasing data transmission efficiency. Enhanced Data Rates for GSM Evolution (EDGE), also known as Enhanced GPRS (EGPRS) or IMT Single Carrier (IMT-SC), is a backward-compatible digital mobile phone technology built as an extension to standard GSM. First deployed in 2003 by AT&T in the United States, EDGE offers a theoretical maximum transfer speed of 384 kbit/s (48 kB/s).<ref name=":1">{{cite web |url=https://www.3gpp.org/technologies/keywords-acronyms/102-gprs-edge |title=GPRS & EDGE |website=3gpp.org |access-date=2019-08-17 |archive-date=2020-04-17 |archive-url=https://web.archive.org/web/20200417193611/https://www.3gpp.org/technologies/keywords-acronyms/102-gprs-edge |url-status=live}}</ref>

=== 2.875G (EDGE Evolution) ===
[[Evolved EDGE]] (also known as EDGE Evolution or 2.875G) is an enhancement of the EDGE mobile technology that was introduced as a late-stage upgrade to 2G networks. While EDGE was first deployed in the early 2000s as part of GSM networks, Evolved EDGE was launched much later, coinciding with the widespread adoption of 3G technologies such as [[High Speed Packet Access|HSPA]] and just before the emergence of [[4G]] networks. This timing limited its practical application.

Evolved EDGE increased data throughput and reduced latencies (down to 80 ms) by utilizing improved modulation techniques, dual carrier support, dual antennas, and [[Turbo code|turbo codes]]. It achieved peak data rates of up to 1 Mbit/s, significantly enhancing network efficiency for operators that had not yet transitioned to 3G or 4G infrastructures. However, despite its technical improvements, Evolved EDGE was never widely deployed. By the time it became available, most network operators were focused on implementing more advanced technologies like [[UMTS]] and [[LTE (telecommunication)|LTE]]. As of 2016, no commercial networks were reported to support Evolved EDGE.