3G TECHNOLOGY:
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.[2]
There are evolutionary standards that are backwards-compatible extensions to pre-existing 2G networks as well as revolutionary standardsthat require all-new networks and frequency allocations.[3] The later group is the 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.
| ITU IMT-2000 | common name(s) | bandwidth of data | pre-4G | duplex | channel | description | geographical areas | |
|---|---|---|---|---|---|---|---|---|
| TDMA Single‑Carrier (IMT‑SC) | EDGE (UWT-136) | EDGE Evolution | none | FDD | TDMA | evolutionary upgrade to GSM/GPRS[nb 1] | worldwide, except Japan and Korea | |
| CDMA Multi‑Carrier (IMT‑MC) | CDMA2000 | EV-DO | UMB[nb 2] | CDMA | evolutionary upgrade to cdmaOne (IS-95) | Americas, Asia, some others | ||
| CDMA Direct Spread (IMT‑DS) | UMTS[nb 3] | W‑CDMA[nb 4] | HSPA | LTE | family of revolutionary standards. | worldwide | ||
| CDMA TDD (IMT‑TC) | TD‑CDMA[nb 5] | TDD | Europe | |||||
| TD‑SCDMA[nb 6] | China | |||||||
| FDMA/TDMA (IMT‑FT) | DECT | none | FDMA/TDMA | short-range; standard for cordless phones | Europe, USA | |||
| IP‑OFDMA | WiMAX (IEEE 802.16) | OFDMA | late addition | worldwide | ||||
While EDGE is part of the 3G standard, most GSM/UMTS phones report EDGE (“2.75G”) and UMTS (“3G”) network availability as separate functionality.
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