The WCDMA Air Interface

WCDMA is the most widely adopted air interface standard for third generation (3G) mobile networks. 3G networks have been designed to supersede second generation (2G) networks, i.e. GSM (Europe and large parts of the world), cdmaOne (Americas), D-AMPS (Americas), and PDC (Japan). The main advances of 3G systems compared with 2G systems are [HT04]: • Higher user peak data rates (several Mbps). • Dynamic adaptation of user data rates (“bandwidth on demand”). • Asymmetric uplink and downlink data rates to fit usual Packet-Switched (PS) traffic characteristics, e.g. web browsing, ftp downloads. • Support of Quality of Service (QoS) differentiation, e.g. in terms of error rates and delay. • Multiplexing of services with different quality and data rate requirements on a single connection. • Improved spectrum efficiency (higher system throughput per unit of allocated frequency spectrum). These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.