UMTS (Universal Mobile Telecommunications System) is a mobile technology of the so-called third generation (3G), successor to the GSM (Global System for Mogile) or 2G technology. This technology allows greater resistance to interference than its predecessor, as well as the simultaneous use of voice and data connections, with download speeds that can reach 2 Mbit/s for users with low mobility or 144 Kbit/s for those moving in vehicles at high speed. These features have made 3G technology one of the most widespread and used for mobile broadband Internet access.
The successive improvements of the UMTS technology have achieved higher download speeds, as is the case of HSPA ( High Speed Packet Access ) with which speeds of up to 14.4 Mbit/s can be reached and the evolution of this, HSPA+, which offers a theoretical maximum of 42 Mbit/s.
It should be noted that the bandwidth capacity of UMTS is shared by all users who are simultaneously connected to the same base station, and at the same time the quality of the connection depends on the distance from the user to the station and on the existing interferences, so the individual download speeds for each user can vary and, in fact, tend to be lower than the theoretical maximum