Planning for small cells in a cellular network: Why it is worth it

Most of the literature on heterogeneous cellular networks is focused on analyzing them as a single macro cell embedded with small cells. In this paper, we take a global perspective and analyze the effect of deploying small cells on the performance of a network comprising several macro cells. We identify potential locations for low-power base-stations based on the coverage patterns of the macro cells and propose three schemes for placing the small cells. Using the model recommended by 3GPP, we show that by judiciously installing just two small cells for every macro base-station at these locations and allocating separate resources to all the small cells on a global level, we can increase the performance of the network significantly (~ 45%). An added benefit of our schemes is that we can switch off the macro base-stations at night (when the number of active users is low) and significantly reduce their operation cost.