i Holma and Mikko Simanainen Introduction 3GPP Base Station Categories Micro Base Stations Pico Base Stations Femtocells Low-Power Remote Radio Heads Distributed Antenna Systems Wi-Fi Integration Wireless Backhaul Products Summary Reference Introduction Small cells are needed in a number of application areas, which also call for a number of different product categories. This chapter presents examples of small cell products. Outdoor small cells, also called as micro cells, provide higher capacity in hot spot areas, better coverage and higher data rates. Micro cells need to have relatively higher transmission power to provide outdoor to indoor penetration and support a high density of users within the cell area. Operators can use public cells also in indoor premises like shopping malls, train stations or office complexes. These cases are typically called pico cells. The required output power is lower in the indoor installations. Also low-power femtocells can be used to provide coverage for small offices. Residential coverage can be organized with home femtocells. The small cell application areas are summarized in Figure 6.1. This chapter is organized as follows. 3GPP base station categories are illustrated in Sec- tion 6.2. Micro and pico base station products are introduced in Sections 6.3 and 6.4, femtocells 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 Public outdoor Public indoor Enterprise Residential Micro Enterprise Femto femto Figure 6.1 Small cell application areas in Section 6.5 and remote RF heads in Section 6.6. The distributed antenna systems (DASs) are illustrated in Section 6.7. The integration of Wi-Fi is discussed in Section 6.8 and backhaul products in Section 6.9. The chapter is summarized in Section 6.10. 6.2 3GPP Base Station Categories 3GPP has defined four base station categories with different RF requirements