Universal Mobile Telecommunications System (UMTS) is one of the third-generation (3G) mobile telephone technologies. It uses W-CDMA as the underlying standard, is standardized by the 3GPP, and is the European answer to the ITU IMT-2000 requirements for 3G Cellular radio systems.
To differentiate UMTS from competing network technologies, UMTS is sometimes marketed as 3GSM, emphasizing the combination of the 3G nature of the technology and the GSM standard which it was designed to succeed.
For a more complete definition, see .
UMTS supports up to 1920 kbit/s data transfer rates; this is still much greater than the 14.4 kbit/s of a single GSM error-corrected circuit switched data channel or multiple 14.4 kbit/s channels in HSCSD, and - in competition to other network technologies such as CDMA-2000, PHS or WLAN - offers access to the World Wide Web and other data services on mobile devices.
From the beginning of 2006, UMTS networks in Japan are being upgraded with High Speed Downlink Packet Access (HSDPA), sometimes known as 3.5G. This will make a downlink transfer speed of up to 14.4 Mbit/s possible. Work is also progressing on improving the uplink transfer speed with the High-Speed Uplink Packet Access (HSUPA).
Marketing material for UMTS has emphasized the possibility of mobile videoconferencing, although experience in Japan and elsewhere has shown that user demand for Video calls is not very high.
Other possible uses for UMTS include the downloading of music and video content, as well as live TV.