Editing 3G (section)

== Overview ==

=== Context ===
A new generation of cellular standards has emerged roughly every decade since the introduction of [[1G]] systems in 1979. Each generation is defined by the introduction of new [[frequency bands]], higher data rates, and transmission technologies that are not backward-compatible due to the need for significant changes in network architecture and infrastructure.

=== Standards ===
Several telecommunications companies marketed wireless mobile Internet services as ''3G'', indicating that the advertised service was provided over a 3G wireless network. However, 3G services have largely been supplanted in marketing by 4G and 5G services in most areas of the world. Services advertised as 3G are required to meet [[IMT-2000]] technical standards, including standards for reliability and speed (data transfer rates). To meet the IMT-2000 standards, Third-generation mobile networks, or 3G, must maintain minimum consistent Internet speeds of 144&nbsp;Kbps.<ref name=":0" /> However, many services advertised as 3G provide higher speed than the minimum technical requirements for a 3G service.<ref>{{cite web |date=2019-11-23 |title=Download Speeds: Comparing 2G, 3G, 4G & 5G Mobile Networks |url=https://kenstechtips.com/index.php/download-speeds-2g-3g-and-4g-actual-meaning |access-date=2019-08-17 |website=Ken's Tech Tips |language=en-US}}</ref> Subsequent 3G releases, denoted [[3.5G]] and [[3.75G]], provided mobile broadband access of several [[Mbps|Mbit/s]] for smartphones and mobile modems in laptop computers.<ref>{{cite web |title=HSPA |url=https://www.3gpp.org/technologies/keywords-acronyms/99-hspa |access-date=2019-08-17 |website=3gpp.org}}</ref>

3G branded standards:
*The [[UMTS]] (Universal Mobile Telecommunications System) system, standardized by 3GPP in 2001, was used in Europe, Japan, [[China]] (with a different radio interface) and other regions predominated by [[GSM]] (Global Systems for Mobile Communications) [[2G]] system infrastructure. The cell phones are typically [[UMTS]] and [[GSM]] hybrids. Several radio interfaces are offered, sharing the same infrastructure:
** The original and most widespread radio interface is called [[W-CDMA]] (Wideband Code Division Multiple Access).
** The [[TD-SCDMA]] radio interface was commercialized in 2009 and only offered in China.
** The latest UMTS release, [[HSPA+]], can provide peak data rates up to 56&nbsp;Mbit/s in the downlink in theory (28&nbsp;Mbit/s in existing services) and 22&nbsp;Mbit/s in the uplink.
*The [[CDMA2000]] system, first offered in 2002, standardized by [[3GPP2]], used especially in North America and South Korea, sharing infrastructure with the [[IS-95]] 2G standard. The cell phones are typically CDMA2000 and IS-95 hybrids. The latest release [[EVDO]] Rev. B offers peak rates of 14.7&nbsp;Mbit/s downstream.

The 3G systems and radio interfaces are based on [[spread spectrum]] radio transmission technology. While the [[Enhanced Data Rates for GSM Evolution|GSM EDGE]] standard ("2.9G"), [[DECT]] cordless phones and [[Mobile WiMAX]] standards formally also fulfill the IMT-2000 requirements and are approved as 3G standards by ITU, these are typically not branded as 3G and are based on completely different technologies.

The common standards complying with the IMT2000/3G standard are:
* [[EDGE (telecommunication)|EDGE]], a revision by the [[3GPP]] organization to the older [[2G]] [[GSM]] based transmission methods, which utilizes the same switching nodes, base station sites, and frequencies as GPRS, but includes a new base station and cellphone RF circuits. It is based on the three times as efficient [[8PSK]] modulation scheme as a supplement to the original [[GMSK]] modulation scheme. EDGE is still used extensively due to its ease of upgrade from existing 2G GSM infrastructure and cell phones.
** [[EDGE (telecommunication)|EDGE]] combined with the [[GPRS]] 2.5G technology is called [[EGPRS]], and allows peak data rates in the order of 200&nbsp;kbit/s, just like the original [[UMTS]] WCDMA versions and thus formally fulfill the IMT2000 requirements on 3G systems. However, in practice, EDGE is seldom marketed as a 3G system, but a [[2.9G]] system. EDGE shows slightly better [[system spectral efficiency]] than the original UMTS and [[CDMA2000]] systems, but it is difficult to reach much higher peak data rates due to the limited GSM spectral bandwidth of 200&nbsp;kHz, and it is thus a dead end.
** [[EDGE (telecommunication)|EDGE]] was also a mode in the [[Digital AMPS|IS-136]] TDMA system, no longer used.
** [[Evolved EDGE]], the latest revision, has peaks of 1&nbsp;Mbit/s downstream and 400&nbsp;kbit/s upstream but is not commercially used.
* The Universal Mobile Telecommunications System, created and revised by the [[3GPP]]. The family is a full revision from GSM in terms of encoding methods and hardware, although some GSM sites can be [[retrofitted]] to broadcast in the UMTS/[[W-CDMA]] format.
** W-CDMA is the most common deployment, commonly operated on the 2,100&nbsp;MHz band. A few others use the 850, 900, and 1,900&nbsp;MHz bands.
*** [[High Speed Packet Access|HSPA]] is an amalgamation of several upgrades to the original W-CDMA standard and offers speeds of 14.4&nbsp;Mbit/s down and 5.76&nbsp;Mbit/s up. HSPA is backward-compatible and uses the same frequencies as W-CDMA.
*** [[HSPA+]], a further revision and upgrade of HSPA, can provide theoretical peak data rates up to 168&nbsp;Mbit/s in the downlink and 22&nbsp;Mbit/s in the uplink, using a combination of air interface improvements as well as multi-carrier HSPA and [[MIMO]]. Technically though, MIMO and DC-HSPA can be used without the "+" enhancements of HSPA+.
* The [[CDMA2000]] system, or IS-2000, including CDMA2000 1x and CDMA2000 High Rate Packet Data (or EVDO), standardized by [[3GPP2]] (''differing'' from the 3GPP), evolving from the original IS-95 CDMA system, is used especially in North America, China, India, Pakistan, Japan, South Korea, Southeast Asia, Europe, and Africa.
** CDMA2000 1x Rev. E has an increased voice capacity (by three times the original amount) compared to Rev. 0 [[EVDO]] Rev. B offers downstream peak rates of 14.7&nbsp;Mbit/s while Rev. C enhanced existing and new terminal user experience.

While DECT cordless phones and [[Mobile WiMAX]] standards formally also fulfill the IMT-2000 requirements, they are not usually considered due to their rarity and unsuitability for usage with mobile phones.<ref>{{cite web|url=http://www.htc.com/www/press.aspx?id=76204&lang=1033|archive-url=https://web.archive.org/web/20081122174257/http://www.htc.com/www/press.aspx?id=76204&lang=1033|url-status=dead|archive-date=2008-11-22|title=HTC – Touch Phone, PDA Phone, Smartphone, Mobile Computer|date=2008-11-22|access-date=2019-08-17}}</ref>

=== Break-up of 3G systems ===
The 3G (UMTS and CDMA2000) research and development projects started in 1992. In 1999, ITU approved five radio interfaces for IMT-2000 as a part of the ITU-R M.1457 Recommendation; [[WiMAX]] was added in 2007.<ref>{{cite press release|url=http://www.itu.int/newsroom/press_releases/2007/30.html|title=ITU Radiocommunication Assembly approves new developments for its 3G standards|publisher=ITU|access-date=1 June 2009| archive-url= https://web.archive.org/web/20090519050045/http://www.itu.int/newsroom/press_releases/2007/30.html| archive-date= 19 May 2009 }}</ref><!--DASHBot-->

There are evolutionary standards (EDGE and CDMA) that are backward-compatible extensions to pre-existing [[2G]] networks as well as revolutionary standards that require all-new network hardware and frequency allocations. The cell phones use UMTS in combination with 2G GSM standards and bandwidths, but ''do not support EDGE''. The latter group is the [[Universal Mobile Telecommunications System|UMTS]] family, which consists of standards developed for IMT-2000, as well as the independently developed standards [[DECT]] and WiMAX, which were included because they fit the IMT-2000 definition.

While [[Enhanced Data Rates for GSM Evolution|EDGE]] fulfills the 3G specifications, most GSM/UMTS phones report EDGE ("2.75G") and UMTS ("3G") functionality.<ref>{{cite web|url=https://www.makeuseof.com/tag/edge-3g-h-etc-mobile-networks/|title=EDGE, 3G, H+, Etc: What Are All These Mobile Networks?|date=2019-02-15|website=MakeUseOf|language=en-US|access-date=2019-08-17}}</ref>