CDMA2000 (also known as C2K or IMT Multi‑Carrier (IMT‑MC)) is a family of 3G mobile technology standards for sending voice, data, and signaling data between mobile phones and cell sites. It is developed by 3GPP2 as a backwards-compatible successor to second-generation cdmaOne (IS-95) set of standards and used especially in North America and South Korea.
CDMA2000 compares to UMTS, a competing set of 3G standards, which is developed by 3GPP and used in Europe, Japan, China, and Singapore.
The name CDMA2000 denotes a family of standards that represent the successive, evolutionary stages of the underlying technology. These are:
- Voice: CDMA2000 1xRTT, 1X Advanced
- Data: CDMA2000 1xEV-DO (Evolution-Data Optimized): Release 0, Revision A, Revision B, Ultra Mobile Broadband (UMB)
All are approved radio interfaces for the ITU's IMT-2000. In the United States, CDMA2000 is a registered trademark of the Telecommunications Industry Association (TIA-USA).