Chapter 26
LTE System Performance
26.1 Introduction
The system performance requirements set for LTE Release 8 in [1] (summarized in Table 1.1) demanded substantial improvements over Release 6 of UMTS.1 For the downlink, the average cell spectral efficiency was required to be three to four times higher than HSDPA,2 and the cell edge spectral efficiency two to three times higher. For the uplink, average and cell edge spectral efficiencies two to three times higher than those of HSUPA3 were required.
This chapter first summarizes the main technical features of LTE Release 8 that deliver these substantial system capacity enhancements. Evaluation results are then presented for spectral efficiency and coverage for typical LTE macrocell deployment scenarios, known as ‘Case 1’ and ‘Case 3’ [2] with inter-site distances of 500 m and 1732 m respectively, together with system performance evaluations in test environments defined by the International Telecommunication Union Radiocommunication Sector (ITU-R) [3].
26.2 Factors Contributing to LTE System Capacity
The preceding chapters have extensively explained the state-of-the-art technical features that significantly improve the system performance of LTE compared to legacy systems. The main difference in both downlink and uplink between LTE Release 8 and UMTS Release 6 (HSDPA/HSUPA) is that the LTE system provides orthogonal resource allocation in the frequency domain, which enables frequency-domain multi-user diversity gain to ...
