The first national consumer UMTS networks launched in 2002 with a heavy emphasis on telco-provided mobile applications such as mobile TV and video calling. Longer term, the 3GPP Long Term Evolution (LTE) project plans to move UMTS to 4G speeds of 100 Mbit/s down and 50 Mbit/s up, using a next generation air interface technology based upon orthogonal frequency-division multiplexing. Work is also progressing on improving the uplink transfer speed with the High-Speed Uplink Packet Access (HSUPA). Currently, HSDPA enables downlink transfer speeds of up to 21 Mbit/s. Since 2006, UMTS networks in many countries have been or are in the process of being upgraded with High-Speed Downlink Packet Access (HSDPA), sometimes known as 3.5G. These speeds are significantly faster than the 9.6 kbit/s of a single GSM error-corrected circuit switched data channel, multiple 9.6 kbit/s channels in High-Speed Circuit-Switched Data (HSCSD) and 14.4 kbit/s for CDMAOne channels. Users in deployed networks can expect a transfer rate of up to 384 kbit/s for Release '99 (R99) handsets (the original UMTS release), and 7.2 Mbit/s for High-Speed Downlink Packet Access (HSDPA) handsets in the downlink connection. UMTS supports maximum theoretical data transfer rates of 42 Mbit/s when Evolved HSPA (HSPA+) is implemented in the network. 11.1 Other, non-UMTS, 3G and 4G standards. 5 Frequency bands and channel bandwidths.2.2.2 TD-SCDMA (UTRA-TDD 1.28 Mcps Low Chip Rate (LCR)).2.2.1 TD-CDMA (UTRA-TDD 3.84 Mcps High Chip Rate (HCR)).Unlike EDGE (IMT Single-Carrier, based on GSM) and CDMA2000 (IMT Multi-Carrier), UMTS requires new base stations and new frequency allocations. The technology described in UMTS is sometimes also referred to as Freedom of Mobile Multimedia Access (FOMA) or 3GSM. UMTS specifies a complete network system, which includes the radio access network ( UMTS Terrestrial Radio Access Network, or UTRAN), the core network ( Mobile Application Part, or MAP) and the authentication of users via SIM ( subscriber identity module) cards. UMTS uses wideband code-division multiple access ( W-CDMA) radio access technology to offer greater spectral efficiency and bandwidth to mobile network operators. Developed and maintained by the 3GPP (3rd Generation Partnership Project), UMTS is a component of the International Telecommunication Union IMT-2000 standard set and compares with the CDMA2000 standard set for networks based on the competing cdmaOne technology. The Universal Mobile Telecommunications System ( UMTS) is a third generation mobile cellular system for networks based on the GSM standard. ( Learn how and when to remove this template message) Please help update this article to reflect recent events or newly available information.
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