sed in Section 5.4 and the solutions for finding the optimal location for the small cell is considered in Section 5.5. The indoor small cells are presented in Section 5.6. The cost aspects are presented in Section 5.7 and the chapter is summarized in Section 5.8. LTE Small Cell Optimization: 3GPP Evolution to Release 13, First Edition. Edited by Harri Holma, Antti Toskala and Jussi Reunanen. © 2016 John Wiley & Sons, Ltd. Published 2016 by John Wiley & Sons, Ltd. LTE Small Cell Optimization Higher spectral More spectrum More cells efficiency Substantially more capacity Figure 5.1 Three main components for increasing network capacity 5.2 Small Cell Motivation The radio network capacity can be enhanced with more spectrum, with higher spectral effi- ciency and with more cells. The new frequency bands between 700 and 2700 MHz are used for increasing the macro cell capacity. Adding more spectrum is relatively simple for getting more capacity. The LTE-Advanced features increase the spectrum efficiency allowing more capacity from the same spectrum. These two solutions are used to squeeze out more capacity from the macro cell sites. When these solutions are exhausted, then small cells will be needed for the capacity reason. These three components for adding capacity are shown in Figure 5.1. With fast growing data traffic, the need for small cells will be evident soon. The additional spectrum and the increased spectral efficiency will not be able to carry the rapidly increasing data traffic in the long term. The small cells will also be driven by the need for better coverage to deliver higher user data rates. At the same time, the small cell implementation has become simpler with small and compact products. Also 3GPP has developed a number of features that make the small cell deployment simpler. The availability of new wireless backhaul solutions has made the small cell rollout faster. The drivers and enablers for the small cells are shown in Figure 5.2. 5.3 Network Architecture Options Before looking into details of the 