Term of the Moment
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Redirected from: 2.5G wireless
Definition: cellular generations
The cellular communications networks are known by their numeric generation: 1G, 2G, 3G, 4G and 5G. We are currently fully deployed in 4G with 5G gaining ground. See also wireless LAN, wireless glossary and Wi-Fi vs. cellular.
5G
The latest cellular generation began in 2018 and will take several years for nationwide adoption. 5G increases speed but at a cost of deploying many more cell towers when the high frequencies are used (see 5G frequency bands). See 5G.
4G - LTE
Starting in the 2011 time frame, GSM and CDMA carriers embraced LTE, which offers higher speeds than 3G. 4G LTE integrates all communications (data, voice and video) using the IP protocol. See LTE and IP Multimedia Subsystem.
4G - WiMAX
Sprint was the first carrier to offer a 4G network in the U.S using the WiMAX technology. It was rolled out to major cities in 2009 but was eventually dropped in favor of LTE. See WiMAX.
4G - HSPA+
In late 2010, the ITU officially designated HSPA+ as a 4G technology, having previously defined it as 3G. See HSPA.
3G - WCDMA/HSDPA and CDMA2000
Launched after the turn of the century, the third generation features faster Internet access with downstream speeds up to 1 Mbps and more. The predominant 3G technologies on the GSM side are WCDMA and HSDPA with CDMA2000 on the CDMA side (see WCDMA, HSPA and CDMA2000). 3G also embraces worldwide roaming for travelers (see GAN).
2G/2.5G - GSM/CDMA, GPRS/EDGE/IS95-B
The second generation refers to the digital voice systems of the 1990s, replacing analog phones and based on the TDMA and CDMA air interfaces. First deployed in Europe, GSM became the predominant TDMA system worldwide. Data networks were added (GPRS, EDGE, IS-95B), and these so-called 2.5G technologies enabled Internet access and email with slow downstream speeds in the Kbps range. See GSM, CDMA, GPRS, EDGE and IS-95.
1G - Analog Voice
Introduced in the late 1970s, the first cellular systems were analog voice. Years later, some 1G cellphones occasionally provided wireless data service to a laptop by connecting them to the laptop's dial-up modem, but hookups were precarious and the data transfer rate was minuscule. See AMPS, TACS and NMT.
Dual Support
5G
The latest cellular generation began in 2018 and will take several years for nationwide adoption. 5G increases speed but at a cost of deploying many more cell towers when the high frequencies are used (see 5G frequency bands). See 5G.
4G - LTE
Starting in the 2011 time frame, GSM and CDMA carriers embraced LTE, which offers higher speeds than 3G. 4G LTE integrates all communications (data, voice and video) using the IP protocol. See LTE and IP Multimedia Subsystem.
4G - WiMAX
Sprint was the first carrier to offer a 4G network in the U.S using the WiMAX technology. It was rolled out to major cities in 2009 but was eventually dropped in favor of LTE. See WiMAX.
4G - HSPA+
In late 2010, the ITU officially designated HSPA+ as a 4G technology, having previously defined it as 3G. See HSPA.
3G - WCDMA/HSDPA and CDMA2000
Launched after the turn of the century, the third generation features faster Internet access with downstream speeds up to 1 Mbps and more. The predominant 3G technologies on the GSM side are WCDMA and HSDPA with CDMA2000 on the CDMA side (see WCDMA, HSPA and CDMA2000). 3G also embraces worldwide roaming for travelers (see GAN).
2G/2.5G - GSM/CDMA, GPRS/EDGE/IS95-B
The second generation refers to the digital voice systems of the 1990s, replacing analog phones and based on the TDMA and CDMA air interfaces. First deployed in Europe, GSM became the predominant TDMA system worldwide. Data networks were added (GPRS, EDGE, IS-95B), and these so-called 2.5G technologies enabled Internet access and email with slow downstream speeds in the Kbps range. See GSM, CDMA, GPRS, EDGE and IS-95.
1G - Analog Voice
Introduced in the late 1970s, the first cellular systems were analog voice. Years later, some 1G cellphones occasionally provided wireless data service to a laptop by connecting them to the laptop's dial-up modem, but hookups were precarious and the data transfer rate was minuscule. See AMPS, TACS and NMT.
Cellphones generally support two technology generations. For example, if this earlier iPhone was in range of a 3G cell tower, it used the higher speed of HSDPA. However, it throttled down to the very low-speed EDGE (E) channel if 3G was not available. See HSPA.