E-UTRA is the air interface of 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) upgrade path for mobile networks. It is an acronym for Evolved UMTS Terrestrial Radio Access,[1] also known as the Evolved Universal Terrestrial Radio Access in early drafts of the 3GPP LTE specification.[1] E-UTRAN is the combination of E-UTRA, user equipment (UE), and a Node B (E-UTRAN Node B or Evolved Node B, eNodeB).
It is a radio access network (RAN) meant to be a replacement of the Universal Mobile Telecommunications System (UMTS), High-Speed Downlink Packet Access (HSDPA), and High-Speed Uplink Packet Access (HSUPA) technologies specified in 3GPP releases 5 and beyond. Unlike HSPA, LTE's E-UTRA is an entirely new air interface system, unrelated to and incompatible with W-CDMA. It provides higher data rates, lower latency and is optimized for packet data. It uses orthogonal frequency-division multiple access (OFDMA) radio-access for the downlink and single-carrier frequency-division multiple access (SC-FDMA) on the uplink. Trials started in 2008.