View source for CDMA2000

{{Short description|Family of 3G mobile technology standards}}
{{About|the mobile phone technology|the channel access method|Code-division multiple access}}
{{Use mdy dates|date=November 2014}}

[[File:Huawei EC226 with USB cable (3384718751).jpg|thumb|[[Huawei]] CDMA2000 [[EVDO]] USB [[wireless modem]] (2009)]]

'''CDMA2000''' (also known as '''C2K''' or '''IMT Multi‑Carrier''' ('''IMT‑MC''')) is a family of [[3G]]<ref>{{cite web
| url = http://www.itu.int/ITU-D/imt-2000/DocumentsIMT2000/What_really_3G.pdf
| title = What really is a Third Generation (3G) Mobile Technology
| access-date = October 28, 2012 | publisher = International Telecommunication Union
| archive-url = https://web.archive.org/web/20110607105523/http://www.itu.int/ITU-D/imt-2000/DocumentsIMT2000/What_really_3G.pdf
| archive-date = June 7, 2011
}}</ref> mobile technology standards for sending voice, data, and [[Signaling (telecommunications)|signaling]] data between [[mobile phone]]s and [[cell site]]s. It is developed by [[3GPP2]] as a backwards-compatible successor to [[2G|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 [[International Telecommunication Union|ITU]]'s [[IMT-2000]]. In the United States, ''CDMA2000'' is a registered trademark of the [[Telecommunications Industry Association]] (TIA-USA).<ref>[http://tess2.uspto.gov/bin/showfield?f=doc&state=4001:kets67.2.3 CDMA2000 trademark application] {{Webarchive|url=https://web.archive.org/web/20170113010120/http://tess2.uspto.gov/bin/showfield?f=doc&state=4001:kets67.2.3 |date=January 13, 2017 }}, uspto.gov, November 17, 2009</ref>

As of 2025, almost all public CDMA2000 networks have been shut down, usually to be replaced by [[LTE (telecommunication)|LTE]] networks.

==1X==
{{List of mobile phone generations}}
'''CDMA2000 1X (IS-2000)''', also known as '''1x''' and '''1xRTT''', is the core CDMA2000 wireless air interface standard. The designation "1x", meaning ''1 times radio transmission technology'', indicates the same [[radio frequency]] (RF) bandwidth as [[IS-95]]: a [[duplex (telecommunications)|duplex]] pair of 1.25&nbsp;MHz radio channels. 1xRTT almost doubles the capacity of IS-95 by adding 64 more traffic channels to the [[forward link]], [[orthogonality|orthogonal]] to (in [[Quadrature phase|quadrature]] with) the original set of 64. The 1X standard supports packet data speeds of up to 153&nbsp;[[Kilobit per second|kbit/s]] with real world data transmission averaging 80–100&nbsp;kbit/s in most commercial applications.<ref>{{cite web|url=http://www.cdg.org/technology/cdma20001x.asp|title=CDG : Technology : CDMA2000 1X|website=CDMA Development Group|access-date=July 28, 2017|archive-date=August 2, 2010|archive-url=https://web.archive.org/web/20100802011151/http://www.cdg.org/technology/cdma20001x.asp|url-status=dead}}</ref> IMT-2000 also made changes to the [[data link layer]] for greater use of data services, including medium and link access control protocols and [[quality of service]] (QoS). The IS-95 data link layer only provided [[best-effort delivery]] for data and circuit switched channel for voice (i.e., a voice frame once every 20 ms).

==1xEV-DO==
{{Main|Evolution-Data Optimized}}[[File:1XEV_Mobile_Phone_Screenshot_blackberry.png|thumb|[[BlackBerry]] smartphone displaying '1XEV' as the service status in the upper right corner (2011)]]
'''CDMA2000 1xEV-DO (Evolution-Data Optimized)''', often abbreviated as '''EV-DO''' or '''EV''', is a [[telecommunication]]s standard for the [[wireless]] transmission of data through [[radio]] signals, typically for [[broadband Internet access]]. It uses [[multiplexing]] techniques including [[code-division multiple access]] (CDMA) as well as [[time-division multiple access]] to maximize both individual user's throughput and the overall system throughput. It is standardized (IS-856) by [[3rd Generation Partnership Project 2]] (3GPP2) as part of the CDMA2000 family of standards and has been adopted by many [[mobile phone]] service providers around the world – particularly those previously employing CDMA networks.

==1X Advanced==
1X Advanced (Rev.E)<ref>{{cite web|url=https://www.cdg.org/news/events/webinar/100513_cdma450_operators/2-ALU-Newbury%20450%20Webinar_3.pdf|title=Evolution of CDMA Roadmap—Voice Perspective|publisher=[[Alcatel-Lucent]]|date=May 13, 2010|access-date=May 17, 2016|archive-date=October 5, 2016|archive-url=https://web.archive.org/web/20161005115836/https://www.cdg.org/news/events/webinar/100513_cdma450_operators/2-ALU-Newbury%20450%20Webinar_3.pdf|url-status=dead}}</ref><ref>{{cite web|url=http://www.3gpp2.org/Public_html/specs/C.S0099-0_v2.0_Guidelines%20for%20using%20cdma2000%201x%20Revision%20E%20Features%20on%20Earlier%20Revisions_20110819.pdf|title=Guidelines for using cdma2000 1x Revision E Features on Earlier Revisions|publisher=[[3GPP2]]|date=July 2011|access-date=May 17, 2016|archive-url=https://web.archive.org/web/20160705073206/http://www.3gpp2.org/Public_html/specs/C.S0099-0_v2.0_Guidelines%20for%20using%20cdma2000%201x%20Revision%20E%20Features%20on%20Earlier%20Revisions_20110819.pdf|archive-date=July 5, 2016|url-status=dead|df=mdy-all}}</ref> is the evolution of CDMA2000 1X. It provides up to four times the capacity and 70% more coverage compared to 1X.<ref>{{cite web|url=http://www.qualcomm.com/solutions/wireless-networks/technologies/1x-advanced|title=1X Advanced|publisher=[[Qualcomm]]|access-date=September 18, 2013|archive-date=July 12, 2014|archive-url=https://web.archive.org/web/20140712002148/http://www.qualcomm.com/solutions/wireless-networks/technologies/1x-advanced|url-status=live}}</ref>

==Networks==
{{See also|List of CDMA2000 networks}}
The CDMA Development Group states that, as of April 2014, there are 314 [[Mobile network operator|operator]]s in 118 countries offering CDMA2000 1X and/or 1xEV-DO service.<ref>{{cite web |url=https://www.cdg.org/resources/cdma_stats.asp |title=CDG : CDMA Statistics |publisher=CDMA Development Group |access-date=June 13, 2015 |archive-date=September 27, 2018 |archive-url=https://web.archive.org/web/20180927201826/http://cdg.org/resources/cdma_stats.asp |url-status=dead }}</ref>{{Update inline|date=August 2020}}

As of 2025, only very few active networks remain, with most of them being private networks maintained for [[machine to machine]] communication for specific critical infrastructure.

== Access authentication in CDMA networks ==
Access authentication in CDMA networks for [[Telecommunication|telecommunications]] and [[computing]] provide network access for a mobile device. Specific methods such as [[CAVE-based Authentication]] ([[IS-95]]/[[1xRTT]]), and [[A12 Authentication]] ([[1xEV-DO]]) are possible. The serving network provides the mobile device access authentication mechanism.<ref>{{Cite web |author=Authority Hub-Where Authentication Meets Artistry |title=Unlocking the Secrets of CDMA Subscriber Identity Module |url=https://mojoauth.com/ciam-101/cdma-subscriber-identity-module |access-date=2025-10-13 |website=Authority Hub - Where Authentication Meets Artistry |language=en}}</ref><ref>{{Cite web |title=CDMA Network Technology: A Decade Of Advances And Challenges |url=https://www.tek.com/en/documents/technical-brief/cdma-network-technology-decade-advances-and-challenges |access-date=2025-10-13 |website=www.tek.com |language=en}}</ref><ref name="Mahdi-2012">{{Cite journal |last1=Mahdi |first1=Mohammed A. |last2=M. Abd-Eld |first2=Mohamed |last3=S. Elgamal |first3=Salwa |last4=Wan |first4=Tat-Chee |date=2012-03-01 |title=Security Analysis and Enhancement of Authentication in CDMA based on Elliptic Curve Cryptography |url=https://scialert.net/abstract/?doi=rjit.2012.106.123 |journal=Research Journal of Information Technology |volume=4 |issue=3 |pages=106–123 |doi=10.3923/rjit.2012.106.123 |issn=1815-7432}}</ref> The exact method employed depends upon the type of service being used:

* [[CAVE-based Authentication]] – Used for access authentication in CDMA/1xRTT
* [[Authentication and Key Agreement|AKA]] – 3G successor to CAVE-based authentication
* [[A12 Authentication]] – Used for access authentication in 1xEV-DO

[[1xEV-DO]] Hybrid MS/AT devices may employ both CAVE-based and A12 authentication since these devices connect to both the [[1xRTT]] and [[1xEV-DO]] networks.

==History==
CDMA2000 technology was developed by [[Qualcomm]] in the late 1990s as an enhancement to the CDMA standard. The intended [[4G]] successor to CDMA2000 was [[Ultra Mobile Broadband|UMB (Ultra Mobile Broadband)]]; however, in November 2008, [[Qualcomm]] announced it was ending development of the technology, favoring [[LTE (telecommunication)|LTE]] instead.<ref>{{cite web |url=https://www.reuters.com/article/marketsNews/idUSN1335969420081113?rpc=401& |title=Qualcomm halts UMB project, sees no major job cuts |archive-url=https://web.archive.org/web/20090414175331/http://www.reuters.com/article/marketsNews/idUSN1335969420081113?rpc=401& |archive-date=April 14, 2009 |url-status=live |website=Reuters |date=November 13, 2008}}</ref> In the USA, the last CDMA2000 network was shut down in 2024<ref>{{Cite web |last=Zeman |first=Benjamin |date=2024-04-26 |title=What the heck happened to CDMA networks? |url=https://www.androidpolice.com/what-happened-to-cdma-networks/ |access-date=2025-09-25 |website=Android Police |language=en}}</ref>.{{Expand section|date=March 2011}}

== Patent licensing ==
In 2007, Qualcomm provided a global patent license for CDMA2000 to the Chinese company Teleepoch.<ref>{{Cite news|date=2007-09-27|title=Qualcomm gives patent license for CDMA2000 units to Chinese firm|language=en|work=Reuters|url=https://www.reuters.com/article/qualcomm-patent-idUKWNAS497420070927|access-date=2021-12-05|archive-date=December 5, 2021|archive-url=https://web.archive.org/web/20211205160023/https://www.reuters.com/article/qualcomm-patent-idUKWNAS497420070927|url-status=live}}</ref>

== See also ==

* [[Channel access method]]
* [[List of authentication protocols]]
* [[List of CDMA2000 networks]]
* [[Mobile broadband]]

==References==
{{Reflist}}

==External links==
* [https://web.archive.org/web/20120829055636/http://www.tiaonline.org/standards/committees/committee.cfm?comm=tr-45 TIA TR-45 Engineering Committee for CDMA Standards]
* [http://www.3gpp2.org/ 3GPP2] {{Webarchive|url=https://web.archive.org/web/20040123013738/http://3gpp2.org/ |date=January 23, 2004 }} Standards and specifications
* [http://www.radio-electronics.com/info/cellulartelecomms/3gpp2/cdma2000-1xrtt-basics-tutorial.php CDMA2000] Overviews of the CDMA2000 standards - 1X to UMB
* [http://cdma2000.info cdma2000.info] Online interactive cdma2000 SDU decoder - covers all releases up to C.S0005-F 2.0

{{Mobile telecommunications standards}}
{{cdma}}
{{Telecommunications}}

{{DEFAULTSORT:Cdma2000}}
[[Category:3rd Generation Partnership Project 2 standards]]
[[Category:Code division multiple access]]