Inside-Out: Can Indoor Femtocells Satisfy Outdoor Coverage and Capacity Needs?

In this paper, we examine the effectiveness of indoor femtocells at providing outdoor coverage in a suburban environment using a realistic macrocell deployment as the basis for the study. An uncoordinated deployment of indoor femtocells is randomly placed on a dedicated carrier and simulated for coverage and capacity. The coverage and capacity gains are found to depend on femtocell penetration. Femtocells are found to be effective at outdoor coverage, covering 29% of the outdoor area at 3% penetration. Coverage is best close to buildings. Throughput gains are sensitive to backhaul assumptions, yielding gains up to 15X for all users with unlimited backhaul, but dropping to about 6X with a 10 Mbps backhaul limit. Gains for outdoor users are smaller, yielding 4.7X and 3.8X with and without the backhaul limitation, respectively.