Graph colouring based fractional frequency reuse for enterprise femtocell networks

Abstract

In this study, the authors propose a novel dynamic channel assignment scheme called graph colouring based fractional frequency reuse (GC‐FFR) to improve system performance for the downlink of enterprise femtocell networks based on orthogonal frequency division multiple access with frequency division duplex. In order to mitigate co‐tier interference from neighbour femtocell access points, the proposed GC‐FFR scheme uses a heuristic method that consists of two steps: multiple femtocell user equipment (FUE) clustering step and dynamic subchannel assignment step. Simulation results show that the proposed GC‐FFR scheme outperforms other schemes in terms of the mean FUE capacity and unsatisfied FUE probability.