CDMA2000

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Mobile phone and data
standards

GSM / UMTS Family

GSM
GPRS
EDGE (EGPRS)
HSCSD

Pre-4G

UMTS Revision 8
- LTE
- HSOPA (Super 3G)

cdmaOne / CDMA2000 Family

cdmaOne

CDMA2000
EV-DO

Pre-4G

Other Technologies

Pre-4G

Frequency bands

CDMA2000 is a hybrid 2.5G / 3G protocol of mobile telecommunications standards that use CDMA, a multiple access scheme for digital radio, to send voice, data, and signalling data (such as a dialed telephone number) between mobile phones and cell sites. CDMA2000 is considered a 2.5G protocol in 1xRTT and a 3G protocol in EVDO.

CDMA (code division multiple access) is a mobile digital radio technology where channels are defined with codes (PN sequences). CDMA permits many simultaneous transmitters on the same frequency channel, unlike TDMA (time division multiple access), used in GSM and D-AMPS, and FDMA, used in AMPS ("analog" cellular). Since more phones can be served by fewer cell sites, CDMA-based standards have a significant economic advantage over TDMA- or FDMA-based standards.

CDMA2000 has a relatively long technical history, and remains compatible with the older CDMA telephony methods (such as cdmaOne) first developed by Qualcomm, a commercial company, and holder of several key international patents on the technology.

The CDMA2000 standards CDMA2000 1xRTT, CDMA2000 EV-DO, and CDMA2000 EV-DV are approved radio interfaces for the ITU's IMT-2000 standard and a direct successor to 2G CDMA, IS-95 (cdmaOne). CDMA2000 is standardized by 3GPP2.

CDMA2000 is a registered trademark of the Telecommunications Industry Association (TIA-USA) in the United States, not a generic term like CDMA. (This is similar to how TIA has branded their 2G CDMA standard, IS-95, as cdmaOne.)

CDMA2000 is an incompatible competitor of the other major 3G standard UMTS. It is defined to operate at 400 MHz, 800 MHz, 900 MHz, 1700 MHz, 1800 MHz, 1900 MHz, and 2100 MHz.

Below are the different types of CDMA2000, in order of increasing complexity:

1 CDMA2000 1xRTT
2 CDMA2000 3x
3 CDMA2000 EV-DO
4 CDMA2000 EV-DV
5 Countries with CDMA2000 operators
6 See also
7 External links

[edit] CDMA2000 1xRTT

CDMA2000 1xRTT, the core CDMA2000 wireless air interface standard, is also known as 1x, 1xRTT, and IS-2000. The designation "1x", meaning "1 times Radio Transmission Technology", indicates the same RF bandwidth as IS-95: a duplex pair of 1.25 MHz radio channels. This contrasts with 3xRTT, which uses channels 3 times as wide (3.75 MHz) channels. 1xRTT almost doubles the capacity of IS-95 by adding 64 more traffic channels to the forward link, orthogonal to (in quadrature with) the original set of 64. Although capable of higher data rates, most deployments are limited to a peak of 144 kbit/s. IS-2000 also made changes to the data link layer for the greater use of data services, including medium and link access control protocols and QoS. The IS-95 data link layer only provided "best effort delivery" for both voice and data.

1xRTT officially qualifies as 3G technology, but it is considered by some to be a 2.5G (or sometimes 2.75G) technology. This allows it to be deployed in 2G spectrum in some countries that limit 3G systems to certain bands.

[edit] CDMA2000 3x

CDMA2000 3x or EV-DO Rev. B utilizes a pair of 3.75 MHz radio channels (i.e., 3 X 1.25 MHz) to achieve higher data rates. The 3x version of CDMA2000 is sometimes referred to as Multi-Carrier or MC. The 3x version of CDMA2000 has not been deployed and is not under development at present.

[edit] CDMA2000 EV-DO

Main article: Evolution-Data Optimized

[edit] CDMA2000 EV-DV

CDMA2000 EV-DV (Evolution-Data/Voice), supports downlink (forward link) data rates up to 3.1 Mbit/s and uplink (reverse link) data rates of up to 1.8 Mbit/s. EV-DV can also support concurrent operation of legacy 1x voice users, 1x data users, and high speed EV-DV data users within the same radio channel.

In 2005, Qualcomm put the development of EV-DV on an indefinite halt, due to lack of carrier interest, mostly because both Verizon Wireless and Sprint are using EV-DO.

[edit] Countries with CDMA2000 operators

Japan: On April 1, 2002, au (by KDDI) launched CDMA 1X brand using CDMA2000 1x technology. On November 28, 2003, au launched EV-DO service in the CDMA 1X WIN brand. au currently providing a EV-DO Rev.A network, the first carrier to do so.
United States: Alltel, Cellcom, Cellular South, Cricket Communications (from Leap Wireless), MetroPCS, Sprint PCS, U.S. Cellular and Verizon Wireless use 1x.
Canada: Most providers are also using 1x including Aliant, Bell Mobility, Manitoba Telecom Services, NMI Mobility, NorthernTel, SaskTel, Solo Mobile, Télébec Mobilité, TELUS Mobility and Virgin Mobile Canada.
Mexico: Iusacell and Unefon are using the 1x technology.
Czech Republic: 2 EV-DO networks -- Telefonica O2 Czech Republic, formerly Eurotel (the world's first CDMA EV-DO in 450 MHz launched in August 2004) and Mobilkom (420 MHz launched in May 2007)
Kenya: CDMA2000 1x is available in Nairobi through Telcom Kenya, Flashcom LTD, and E.M. Communications Ltd., which is branded as "popote" in Kenya.
Malawi: CDMA2000 1x and EV-DO will be available in Malawi in 2008 through Access Communications Ltd the Second National Operator in the 800Mhz Band.
Sri Lanka: CDMA technology was introduced in 2005 and currently there are 5 CDMA2000 operators. Sri Lanka Telecom (SLT) www.slt.lk moved to CDMA2000 service supplier and has ZTE EVDO Rev. 0 network and all island covered 1x data service. Suntel www.suntel.lk and Lanka Bell www.lankabell.com are using 800 MHz range. Both operators have islandwide 1x data service and these days trying to enter EVDO rev0 data market. DBN and Tritel are expecting to enter the Sri Lanka CDMA2000 market in June 2007 on 450 MHz. Among the five operators, Lanka Bell has the largest CDMA2000 market share.
People's Republic of China: China Unicom is the major mobile wireless service provider on CDMA2000 1x.
Nepal: Nepal Telecom and United Telecom Limited are providing the services to customers on CDMA2000 1x.
India: BSNL, Reliance Communications and Tata Teleservices are major wireless services providers on CDMA2000 1x.
Indonesia: Sampoerna Telekom Indonesia (Ceria) is the major mobile wireless service provider on CDMA2000 1x . The other CDMA2000 providers are fixed wireless (such as Bakrie Telkom, Telkom Flexi, and Indosat's Starone).
Brazil: VIVO is the only provider for CDMA2000 1x.
Bangladesh: Pacific Telecom's CityCell is CDMA2000 1x RTT provider.
Venezuela: Movilnet and movistar are the country's wireless services providers on CDMA2000 1x.
Pakistan: PTCL, World Call, and GoCdma provide CDMA2000 connections..
Morocco: Wana has recently launched a CDMA2000 service.
Moldova: Unite offers both mobile and fixed telephony and data services using CDMA2000 in the 450 MHz band since March 2007.
South Africa: Neotel has been awarded 800 mHz Spectrum by icasa and will launch CDMA2000 services later this year.
Ukraine: PEOPLEnet is the provider CDMA2000 1x and EV-DO Rev A since 2007 year.
Latvia: Triatel offers mobile and fixed telephony and data services using CDMA2000.
New Zealand: Telecom is the only CDMA2000 network, operating both 1x and EVDO Rev A nationwide, however this is only guaranteed for the next 5 years after recently announcing a switch to GSM [1].
Estonia: CDMA2000 1x network operating in 450 MHz spectrum is available since July 2007 by Eesti Energia subsidiary Televõrgu AS by name Kõu, covering all of country territory.
Russia: Skylink is CDMA2000 1x and EV-DO operator in many regions, including Moscow Oblast, Leningrad Oblast and others. BWC is CDMA2000 1x and EV-DO operator in Irkutsk Oblast. ETK is cdma2000 1x and EV-DO operator in Krasnoyarsk Krai.
Romania: Zapp Mobile provides CDMA2000 in the 450 MHz band (for phones and modems).
Portugal: Zapp Mobile provides CDMA2000 in the 450 MHz band (for modems).
Norway: Nordisk Mobiltelefon provides CDMA2000 in the 450 MHz band (for modems).
Taiwan: Asia Pacific Telecom (APT) provides CDMA2000 in the 800 MHz band
Thailand: Hutch provides CDMA2000-1xRTT service and is in process of deploying EV-DO in 25 provinces. CAT Telecom is currently in the final phase of implementing an EV-DO network in the remaining provinces of Thailand. They plan to join forces and co-market a nationwide EV-DO service under a single brand, which has yet to be decided.