CDMA2000 (also known as IMT Multi‑Carrier (IMT‑MC)) is a family of 3G mobile technology standards, which use CDMA channel access, to send voice, data, and signaling data between mobile phones and cell sites. The name cdma2000 actually denotes a family of standards that represent the successive, evolutionary stages of the underlying technology. These are, in order of evolution:
- CDMA2000 1xRTT
- CDMA2000 1xEV-DO: Release 0, Revision A, Revision B
- CDMA2000 1xEV-DO Revision C or Ultra Mobile Broadband (UMB)
- CDMA2000 1xEVDV
All are approved radio interfaces for the ITU's IMT-2000. CDMA2000 has a relatively long technical history and is backward-compatible with its previous 2G iteration IS-95 (cdmaOne). In the United States, CDMA2000 is a registered trademark of the Telecommunications Industry Association (TIA-USA).