Performance analysis of flexible reuse in cellular networks

Flexible frequency reuse schemes namely fractional frequency reuse (FFR) and soft frequency reuse (SFR) are suggested in the literature to improve the cell edge throughput over unity frequency reuse in orthogonal frequency division multiple access networks. In this study, the authors focus on real time (RT) traffic for which blocking probability and Erlang load are the important performance metrics. Both FFR and SFR have signal-tointerference-plus noise-ratio (SINR) threshold and power ratio as important design parameters, whereas FFR has a bandwidth partitioning ratio as an additional parameter. They investigate the cell capacity and the cell edge performance in terms of Erlang load with blocking probability constraint brought about by the suitable choice of these parameters. They also analyze the fairness aspect which is a critical indicator of user satisfaction. They give a complete comparison between FFR and SFR for the cell edge as well as total cell for both RT and BE traffics. For RT traffic, with proper choice of the parameters, the cell edge and the total cell performance in FFR and SFR is improved by a notable gain over the reference scheme. For BE traffic, both schemes provide significant gains at cell edge over reuse one and reuse three schemes.