17
UTRAN Long-Term Evolution
17.1 Introduction
This chapter presents the Universal Mobile Telecommunication Services (UMTS) Terrestrial Radio Access Network (UTRAN) Long-Term Evolution (LTE) work, which is defining a new packet-only wideband radio with flat architecture as part of the 3rd Generation Partnership Project (3GPP) radio technology family in addition to Global System for Mobile Communications (GSM)/General Packet Radio System (GPRS)/Enhanced Data rates for GSM Evolution and Wideband Code Division Multiple Access (WCDMA)/High-Speed Downlink Packet Access (HSDPA)/High-Speed Uplink Packet Access (HSUPA). This chapter covers the 3GPP schedule, background requirements and the technology principles around the UTRAN LTE physical layers, protocols and architecture as well as the outlook for the LTE-Advanced work in 3GPP. The first set of LTE Release 8 specifications was finalized at the end of 2007, but it took until March 2009 till a commercial baseline specification (from the LTE UE perspective) was achieved with all the corrections. The next Release, Release 9, was more or less completed by the end of 2009. The work on LTE-Advanced is aiming for 3GPP Release 10, with the first specs due towards the end of 2010 and finalization of the work in the first half of 2011.
3GPP started to investigate UTRAN LTE during 2004 by identifying the requirements from different players in the field. Following the workshop on the topic, it was agreed to start ...
