WCDMA stands for Wideband Code Division Multiple Access and is the 3G technology that employs the Direct-Sequence Code Division Multiple Access (DS-WCDMA) channel access method and the Frequency Division Duplexing (FDD) method to provide high-speed and high capacity service

Third generation (3G) wireless capability has been developed in response to a growing demand in data services

There are several different radio access technologies defined within ITU, based on either CDM or TDMA technology. Different regional solutions were proposed as solutions to the requirements of IMT-2000. These included Time Division Multiple Access (TDMA) and Code Division Multiple Access (CDMA) utilizing Frequency Division Duplex (FDD) and Time Division Duplex (TDD)

The fragmentation of the proposals led to the creation of two working groups. One group is known as the Third Generation Partnership Project (3GPP) which is working on the Unified Mobile Telecommunication Standard (UMTS) based on WCDMA.

The other group is known as 3GPP2 works on CDMA 2000

Organization 3rd Generation Partnership Project (3GPP) has continued that work by defining a mobile system that fulfils the IMT-2000 standard, This system a called Universal Mobile Telecommunication System (UMTS)

ITU finally approved a family of five 3G standards which are part of the 3G framework known as IMT-2000. These standards are:

WCDMA (UMTS 99)

WCDMA (HSPA)

CDMA2000

TD-CDMA

TD-SCDMA

WCDMA features two modes:

Frequency Division Duplex (FDD): Separately users by employing both codes as well as frequencies. One frequency is used for the uplink, while other is used for downlink

Time Division Duplex (TDD): Separates users by employing codes, frequencies and time wherein the same frequency is used for both uplink and downlink

WCDMA does no need base station timing synchronization

WCDMA provides significant flexibility to provide support of multiple users at independent data rates. The flexibility necessitates the utilization of multiple complex waveforms for validation and test.