Compatible with abundant services and applications of GSM and GPRS, the WCDMA system has an open integrated service platform to provide a wide prospect for various 3G services. This chapter introduces the categories and features of 3G services, and presents several typical types of services and their implementation methods, so that the readers may gain a general understanding of 3G services.
2.1.1 Categories of 3G Services
l Basic telecom services, including voice service, emergency call service and SMS.
l Supplementary services, the same as the supplementary services defined in GSM.
l Bearer services, including circuit bearer service and packet bearer service.
l Intelligent service, an intelligent network service based on CAMEL mechanism inherited from the GSM system.
l Location services, services related to location information, such as charging by area, mobile yellow page and emergency locating.
l Multimedia services, including circuit real-time multimedia service, packet real-time multimedia service and non real-time store-and-transfer multimedia message service.
The above services are roughly classified. Actually these services may overlap. For example, charging by area is not only a location service, but also an intelligent service.
2.1.2 Features of 3G Services
3G (WCDMA) services are inherited from 2G (GSM) services. In a new architecture, new service capabilities are generated, and more service types are available. Service characteristics vary greatly, so each service features differently. Generally, there are features as follows:
l The real-time services such as voice service generally have the QoS requirement.
l Compatible backward with all the services provided by GSM.
l The concept of multimedia service is introduced.