Universal Mobile Telecommunications System (UMTS) is one of the
third-generation (3G) cell phone technologies, which is also being developed into a
4G technology. Currently, the most common form of UMTS uses
W-CDMA as the underlying air interface. It is standardized by the
3GPP, and is the European answer to the
ITU IMT-2000 requirements for
3G cellular radio systems.
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