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WCDMA (UMTS)
TDCDMA
CDMA2000
WCDMA (DoCoMo)
TD-SCDMA
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Mobiles
Bluetooth
HomeRF/SWAP
WAP
GPRS, HSCSD
EDGE
CAMEL, IN
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Cdma2000
Cdma2000 specification was developed by the Third Generation Partnership Project 2 (3GPP2), a partnership consisting of five telecommunications standards bodies: ARIB and TTC in Japan, CWTS in China, TTA in Korea and TIA in North America. Cdma2000 has already been implemented to several networks as an evolutionary step from cdmaOne as cdma2000 provides full backward compatibility with IS-95B. Cdma2000 is not constrained to only the IMT-2000 band, but operators can also overlay acdma2000 1x system, which supports 144 kbps now and data rates up to 307 kbps in the future, on top of their existing cdmaOne network.
The evolution of cdma2000 1x is labeled cdma2000 1xEV. 1xEV will be implemented in steps: 1xEV-DO and 1xEV-DV. 1xEV-DO stands for "1x Evolution Data Only". 1xEV-DV stands for "1x Evolution Data and Voice". Both 1xEV cdma2000 evolution steps will use a standard 1.25 MHz carrier. 1xEV-DO probably will be available for cdma2000 operators during 2002 and 1xEV-DV solutions will be available approximately late 2003 or early 2004.
Cdma2000 1x EV-DO and cdma2000 3x are an ITU-approved, IMT-2000 (3G) standards. Cdma2000 3x is part of what the ITU has termed IMT-2000 CDMA MC (Multi Carrier). It uses less that 5 MHz spectrum (3x 1.25 MHz channels) to give speeds of over 2 Mbps. Cdma2000 1x with lower data speed is considered to be a 2.5G technology.
Cdma2000 Technical summary
Frequency band: Any existing band.
Minimum frequency band required: 1x: 2x1.25MHz, 3x: 2x3.75
Chip rate: 1x: 1.2288, 3x: 3.6864 Mcps
Maximum user data rate: 1x: 144 kbps now, 307 kbps in the future 1xEV-DO: max 384 kbps - 2.4 Mbps, 1xEV-DV: 4.8 Mbps.
Frame length: 5ms, 10ms or 20ms
Power control rate: 800 Hz
Spreading factors: 4 ... 256 UL
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