CDMA2000

This article is about the mobile phone technology. For the channel access method, seeCode-division multiple access.

HuaweiCDMA2000EVDOUSBwireless modem

CDMA2000(also known asC2KorIMT Multi‑Carrier(IMT‑MC)) is a family of3Gmobile technology standards for sending voice, data, andsignalingdata betweenmobile phonesandcell sites.It is developed by3GPP2as a backwards-compatible successor tosecond-generationcdmaOne(IS-95) set of standards and used especially in North America and South Korea.

CDMA2000 compares toUMTS,a competing set of3Gstandards, which is developed by3GPPand 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 theITU'sIMT-2000.In the United States,CDMA2000is a registered trademark of theTelecommunications Industry Association(TIA-USA).

1X

CDMA2000 1X (IS-2000),also known as1xand1xRTT,is the core CDMA2000 wireless air interface standard. The designation "1x", meaning1 times radio transmission technology,indicates the sameradio frequency(RF) bandwidth asIS-95:aduplexpair of 1.25 MHz radio channels. 1xRTT almost doubles the capacity of IS-95 by adding 64 more traffic channels to theforward link,orthogonalto (inquadraturewith) the original set of 64. The 1X standard supports packet data speeds of up to 153kbit/swith real world data transmission averaging 80–100 kbit/s in most commercial applications.IMT-2000 also made changes to thedata link layerfor greater use of data services, including medium and link access control protocols andquality of service(QoS). The IS-95 data link layer only providedbest-effort deliveryfor data and circuit switched channel for voice (i.e., a voice frame once every 20 ms).

1xEV-DO

Main article:Evolution-Data Optimized

BlackBerrysmartphone displaying '1XEV' as the service status in the upper right corner.

CDMA2000 1xEV-DO (Evolution-Data Optimized),often abbreviated asEV-DOorEV,is atelecommunicationsstandard for thewirelesstransmission of data throughradiosignals, typically forbroadband Internet access.It usesmultiple xingtechniques includingcode-division multiple access(CDMA) as well astime-division multiple accessto maximize both individual user's throughput and the overall system throughput. It is standardized (IS-856) by3rd Generation Partnership Project 2(3GPP2) as part of the CDMA2000 family of standards and has been adopted by manymobile phoneservice providers around the world – particularly those previously employing CDMA networks.

1X Advanced

1X Advanced (Rev.E)is the evolution of CDMA2000 1X. It provides up to four times the capacity and 70% more coverage compared to 1X.

Networks

See also:List of CDMA2000 networks

The CDMA Development Group states that, as of April 2014, there are 314operatorsin 118 countries offering CDMA2000 1X and/or 1xEV-DO service.

History

CDMA2000 technology was developed byQualcommin the late 1990s as an enhancement to the CDMA standard.

The intended4Gsuccessor to CDMA2000 wasUMB (Ultra Mobile Broadband);however, in November 2008,Qualcommannounced it was ending development of the technology, favoringLTEinstead.

Patent licensing

In 2007, Qualcomm provided a global patent license for CDMA2000 to the Chinese company Teleepoch.

External links

• TIA TR-45 Engineering Committee for CDMA Standards
• 3GPP2ArchivedJanuary 23, 2004, at theWayback MachineStandards and specifications
• CDMA2000Overviews of the CDMA2000 standards - 1X to UMB
• cdma2000.infoOnline interactive cdma2000 SDU decoder - covers all releases up to C.S0005-F 2.0