This is the term used to describe Universal Mobile Telecommunications System (UTMS), which is a third generation wireless technology used by mobile phone operators to deliver faster data rates of up to 384Kbps downstream and 64Kbps upstream.
Meanwhile 3.5G is often also used to describe HSPA technology (HSUPA, HSDPA), which is detailed elsewhere on this page. HSPA is based off UMTS technology but capable of delivering far faster speeds and is technically still classed as part of 3G.
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