3
3GPP Evolved Packet System (EPS)
3.1 Introduction
UMTS (Universal Mobile Telecommunication System) refers to the interconnection of a new type of Radio Access Network, the UTRAN (UMTS Terrestrial Radio Access Network), to the adapted pre-Release 99 GSM/GPRS Core Network infrastructure. A new radio interface called W-CDMA (Wideband Code Division Multiple Access) was specified in Release 99. From there onwards, multiple releases have been standardized to continue the evolution of UMTS. HSPA (High Speed Packet Access) was the next step in the evolution and it was standardized in Releases 5-6. After HSPA, 3GPP has also defined Evolved HSPA (HSPA+) in Release 7. The longer term evolution of UMTS/HSPA networks has been named as EPS (Evolved Packet System). EPS is composed of E-UTRAN (Evolved UTRAN) and EPC (Evolved Packet Core) which are commonly known as 3G-LTE (Long Term Evolution) and SAE (System Architecture Evolution) respectively. E-UTRAN is focused on the evolution of the Radio Access Network while EPC looks into the future needs of the core network. EPS is defined primarily in 3GPP Release 8 which was completed in December 2008.
Chapter 3 primarily focuses on E-UTRAN as defined in Release 8, its performance aspects and its evolution. The second section looks into the different releases of 3GPP while the third and fourth sections describe the LTE objectives and LTE air interface respectively. Layers 1–3 are described in Sections 5–7 whereas the key attributes of LTE are listed ...
