e mobile networks - more than 100% annual growth pushes the capacity limits of the macro cell network. It is not possible to add more frequencies to the macro sites in busy areas simply because all the spectrum is already fully 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 utilized. Acquiring more spectrum through auctions takes time and can be very expensive, and may also require new frequency variants in the devices resulting in an additional delay in providing capacity offload. Overtime as the capacity demand of the mobile networks grows, additional capacity sites are sometimes needed to augment the capacity and adjust the coverage grid SO that there is a higher density of macro sites in high traffic areas. The next evolution to this concept is to build small cells in hotspot traffic areas as an underlay to the existing macro cell network. The primary motivation behind using small cells is to use a non-uniform network topology that more closely mirrors the non-uniform traffic distribution by placing the network closer to the end user to improve the overall performance and wireless capacity. There are a number of reasons why there is significant interest from operators to utilize this approach: Customer high traffic areas are non-uniformly distributed SO small cells can often be the more practical and efficient solution to address specific hotspot congestion areas. The smaller physical form factor of small cells will help mitigate zoning and installation concerns that often impede rapid deployment. The current and expected wireless data usage growth is outpacing the expected pipeline of usable wireless spectrum assets that could be deployed to support the hotspot traffic. Improving the signal level and signal quality is important especially in the indoor locations to guarantee reliable data connections. Existing wireless access 