Introduction to Radio and Core Networks of UMTS

Mobile networks were first designed for one single service which was voice telephony. The very first mobile radio telephone system was introduced in 1918 by the German national railway Deutsche Reichsbahn, which offered their first-class passengers a radiobased telephone link in the Berlin area (Feyerabend et al. 1927, p. 872). However, the first large mobile network was established in 1958. It was the so-called A-Netz. The terminals were huge and their cost immense. Also, the number of subscribers was limited due to the simple implementation. The successor, the so-called B-Netz, was introduced in 1972. An important new feature of the system allowed the subscribers to set up a call on their own. In the previous networks a central operator was involved in any call setup procedure. The last analogue technology was the C-Netz, which began in 1986 and was shut down in 2000. The terminals were still quite expensive, but at only 6.5 kg they were real lightweights compared to the previous generations. Mobile telephony as we know it today began in the early 1990s. In 1990 the second generation (2G) of mobile communication technology, namely the Global System for Mobile Communications (GSM), was introduced by the European Telecommunications Standards Institute (ETSI), supporting digital transmission of voice data. The number of mobile terminals started to ramp up very quickly and after 15 years they had already exceeded the number of fixed telephone systems in Austria.