Universal Mobile Telecommunication System (UMTS)
Introduction

The second generation of telecommunication systems, such as GSM, enables easy transmission of voice traffic over wireless environment. Nevertheless, 2G networks are incapable to satisfy all data requirements as these are continually increasing and are driven by fast development of mobile applications demanding high data transmissions (video on demand, downloading of high quality images, etc.). To that end, the next generation of mobile networks, known as 3G, has been developed to meet these requirements.

In order to work toward global 3G mobile radio standard, the Third Generation Partnership Project (3GPP) had been founded in December, 1998. The 3GPP consists of members of the standardization bodies from all around the world such as Europe (ETSI), USA (ANSI) or Japan (ARIB). The 3GPP have been working on a common 3G radio standard, which is usually referred to as UMTS. Nonetheless, the 3G term is not applied on one particular technology or standard but it encompasses many technical specifications that have been gradually approved to enhance former UMTS in order to increase still increasing demands.

In the next chapters we will describe in more detail the frequency allocation, basic transmission principles and WCDMA (Wideband Code Division Multiple Access) access method adopted in UMTS. Further, evolution of 3G technology focusing especially on high speed data access is delivered. In addition, we will depict the services and applications used in 3G networks together with QoS (Quality of Service) classifications.