The CDMA2000 specification was created and developed by the Third Generation Partnership Project 2 or 3GPP2which is a partnership that consists of 5 telecommunication standard bodies: TTC and ARIB in JapanTTA in KoreaTIA in North America and CWTS in China. CDMA2000 has been implemented to a lot of networks as an evolutionary step from CDMAOne. CDMA2000 gives a full backward compatibility with IS-95B.
CDMA2000 is not contained only into a single IMT-2000 and although managers have the ability to overlay ACDMA2000 1x system. The system backs 144 Kbps at present with data rates running up to 307 Kbps in the near future over the other present CDMAOne network.
Evolving the Technology
CDMA2000 1xEV is the other name of the evolved CDMA2000. This technology will be implemented via a number of steps namely the 1xEV-DV and 1xEV-DO. 1xEV-DO which represents 1x Evolution Data Only. 1xEV-DV represents 1x Evolution Data and Voice. The two 1xEV CDMA2000 evolution steps will use a carrier standard 1.25 Mhz. 1xEV-DO will most likely be available for the operators CDMA2000 during 2002. The solutions for 1xEV-DV were made available in 2004.
CDMA2000 3x and CDMA2000 1x EV-DO are approved by ITU and IMT-2000 3G basics. CDMA2000 3x is a portion of what the ITU has called IMT-2000 CDMA MC or Multi Carrier. This uses a lower than 5 MHz spectrum via 3x 1.25 MHz channels to provide speeds of more than 2 Mbps.
The Technical Summary
As for the summary of the CDMA2000the frequency band can be any type or existing and. The minimum frequency band needed for 1x is 2 x 1.25 MHz. For 3xthe required is 2 x 3.75 Mhz. Chip rate for 1x is 1.2288. For 3xchip rate is 3.6864 Mcps. The maximum user data rate for 1x is 144 Kbps at present and 307 Kbps in the near future. As for 1xEV-DOthe max rate is 384 Kbps to 2.4 Mbps. The frame length is 5 ms10 ms or 20 ms. As for power control rateit is at 800 Hz. The spreading factors are 4 256 UL.
On WCDMA
W-CDMA in 3G is known as wideband code division multiple access. It is one of the main technologies used for the implementation of 3G cellular systems. It is founded on the radio access method give by ETSI Alpha group with the features and specifications finalized in 1999. The implementation of W-CDMA will cover very technical details. The complexity of the systems can be seen from various angles. These include the complexity of the receiver the complexity of the overall system and the complexity of the single algorithm.
In W-CDMAthe interface allows users of 3G to instantly send and get various data rates. UMTS networks will need the support of all current 2G services and several new services and applications. You should consider if this will be the right technique for you.
