 the future terminal carrier aggregation capabilities. The 3.5 GHz band may be used in the macro cells especially in those areas where the macro cell density is high. If the macro cell grid is sparse, then 3.5 GHz may be used as the dedicated small cell frequency. The high frequencies, like 5 GHz unlicensed bands, will be used in the small cells. The small cells can share the same frequency with macro cells or use a dedicated frequency. The frequency usage aspects are considered in Table 5.3. The co-channel deployment maximizes the spectral efficiency but requires more careful inter-cell interference management. The dedicated frequency deployment is simple from the interference management point of view. More detailed interference management solutions are considered in Chapter 7. Figure 5.5 shows an example dense urban deployment of pico cells using two different spectrum options: shared in-band spectrum and dedicated out-band spectrum. To reach an Small Cell Deployment Options Table 5.3 Frequency usage in small cells Co-channel with macro cells Dedicated small cell (in-band) frequency (out-of-band) Interference management Preferable clear dominance Simple interference between macro and small areas needed for small management cells cells. Enhanced ICIC (eICIC) can be utilized. Mobility management Intra-frequency handover Inter-frequency handovers between macro and small needed which requires cells proper measurement triggering Capacity Maximizes the overall spectral Beneficial for high number of efficiency small cells outage of 5% only ~1/3 of the small cells would be needed to provide the same capacity with out-band small cells compared to in-band small cells. We see a breakeven of in-band versus out-of-band deployment of around two small cells per macro cell depending on the traffic load. An in-band solution is more attractive with a lower number of micro cells. Meanwhile out-of-band performs better with a high micro cell density. The in-band deployment increases network capacity and coverage and is recommended 