Characteristics of WCDMA Technology

The main technical specifications of WCDMA are: support high-speed data transmission (384kb/s when moving slowly, 2mb/s when walking indoors), asynchronous BS, support variable speed transmission, frame length 10ms, chip rate 3.84mb/s. The main features are as follows:

Base Station synchronization mode: support asynchronous and synchronous base station operation mode, network convenient, flexible;

Modulation mode: The behavior BPSK, the next behavior Qpsk; Demodulation method: Pilot-assisted coherent demodulation;
Access mode: DS-CDMA mode, three coding methods: in the voice channel using convolution code (R=1/3,K=9) for internal coding and Veterbi decoding, in the data channel using Reedsolomon coding in the control channel using convolutional code (R=1/2,K=9) Conduct internal coding and VETERBI decoding;
Adapt to the transmission of a variety of rates, flexible to provide a variety of services, and according to different business quality and business rate allocation of different resources, at the same time for multirate, multimedia services can be changed by changing the spread ratio (for low speed 32kb/s, 64kb/s, 128kb/s Business) and multiple code parallel transmission ( For higher than 128kb/s business) the way to achieve; The fast and high efficiency of power control reduces the system's multiple access interference greatly, improves the system capacity and reduces the transmission power;
The core network is based on the evolution of the GSM/GPRS network and maintains the compatibility with the GSM/GPRS network; There is no need to sync between BTS because BS can send and receive asynchronous PN code, that is, BS can track the PN code issued by each other, while Ms can also use additional PN code for capture and tracking, so you can get synchronization to support the handover and macro diversity, while there is no need for synchronization between BTS; support soft switching and softer switching, The switching mode includes three kinds, namely: the sector soft switch, the small interval soft switch and the carrier frequency between hard switching.

WCDMA's initiators are mainly European and Japanese standardization organizations and manufacturers, WCDMA inherited the second generation of mobile communication system, the high level of GSM standardization and the characteristics of good openness, standardization progress smoothly, network operators can introduce GPRS network equipment and new business in GSM network, cultivate data business consumer groups , and gradually transition to 3G. (Computer science)