A third generation or 3G standard which uses a direct-sequence code with division multiple access, channel access method and also a high-frequency division duplexing, is known as Wideband Code Division Multiple Access which is aimed only to provide high speed and reliable service to the people.
WCDMA is one of the most widely sued variants for the Universal Mobile Telecommunications Systems or UMTS. This was first developed in Japan’s NTT DoCoMo and formed the base of the Freedom of Multimedia Access or FOMA 3G network.
The Wideband Code Division Multiple Access is a belongs to the UMTS and has been produced along with the 3G Partnership Program. It has been included with essential cellular networks which refer to the Global System for Mobile or the GSM communications system worldwide.
This Wideband Code Division Multiple Accesses (WCDMA) currently features two modes:
- Frequency Division Duplex (FDD):It keeps the difference between users and the code frequencies. One of the frequency is used for uplink whereas the second one is used for downlink.
- Time Division Duplex (TDD): this mode separates the users based on codes, time and the frequencies where the same frequency is used in both the process of uplink and downlink.
Even though Wideband Code Division Multiple Access has been mostly designed to work the core GSM networks which have evolved, the code uses Division Multiple Acess for the function of an air interface. Most of the 3G systems are currently in operation to employ CDMA whereas the others remaining are using the TDMA or Time Division Multiple Access.
CDMA also allows several users, at the same time, to share a channel whereas the TDMA users share the same channel at different slots of time. Wideband Code Division Multiple Accesses (WCDMA)? Also helps to increase the overall speed of the bandwidth being an air interface.