ples of how these advanced RRM functions are realized in LTE and how, together, they will make LTE a high-performance, competitive system for many years to come. 4.6.1 Outlook Although the first release of the LTE standard (release 8 in 3GPP release number- ing) has not yet been completed at the time of writing, the discussion about future enhancements of the LTE system, which will fulfill or even exceed requirements being set by ITU for IMT Advanced systems, have already started in the 3GPP. The work in ITU is targeted to set only the requirements that a system should fulfill in order to qualify as IMT-Advanced capable. At the time of writing, this work of defining the requirements is ongoing in ITU [12]. © 2009 by Taylor & Francis Group, LLC Long Term Evolution: GPP LTE Radio and Cellular Technology Such an enhanced version of the LTE system is also often referred to as LTE- Advanced. The LTE-Advanced system will be fundamentally based on the LTE technology but will include some additions that enable improvement of the system toward and beyond IMT Advanced requirements. The improvements are not point- ing exclusively in the direction of achieving even higher spectral efficiencies with more advanced radio link algorithms, etc., but, rather, are focusing more on other aspects of the system. For example, such issues as spectrum aggregation, self-con- figuration, self-optimization, advanced repeater structures, and distributed antenna systems (DASs) are being discussed in the 3GPP [13] as candidate technologies for LTE-Advanced. Acronyms 3rd Generation Partnership Project admission control acknowledgment aggregated maximum bit rate access point application allocation retention priority block error rate BM-SC broadcast multicast service center bearer service buffer status report cyclic delay diversity code division multiple access channel feedback reporting CPICH common pilot indicator channel channel quality indicator collision zone distributed antenna system discrete Fourier transform downlink eNode B evolved pack