On dynamic fractional frequency reuse for OFDMA cellular networks

In this paper, we present a dynamic fractional frequency reuse (D-FFR) scheme for OFDMA based cellular networks. The proposed approach is extended from the so-called strict FFR architecture by allowing a fraction of the cell-edge frequencies to be shared by the edge users of the neighboring cells. This sub-band sharing flexibility not only alleviates the spectral deficiency of the strict FFR against soft frequency reuse (SFR) but also improves the already superior performance metrics such as the cell-edge signal-to-noise-plus-interference-ratio (SINR), outage probability and network sum rate throughput. It also provides robustness against sudden and uneven bursts of traffic in one of the cells of the networks. To this end, we provide an analytical framework to determine the coverage probability and the achievable rate of the proposed D-FFR scheme using the parametric models based on stochastic geometry and illustrate the benefits over static (strict or soft) frequency reuse methods via simulation results.