Subband allocation for femtocells in presence of asynchronous interference in fractional frequency reuse based OFDMA networks

This paper addresses the subband allocation for femtocells in the presence of asynchronous cochannel interference in OFDMA based cellular network. A method is presented here to find the subband least affected by interference and this subband is then used for communication within femtocells. Using an energy based approach, synchronized as well as asynchronized arrival of interfering frames are addressed in the analysis carried out for subband selection. Two-slope model is used to account for path loss. Channel effects are also embodied into the analytical framework. Analytical and simulation results are in good agreement and they provide insight into various parameters, which can be adjusted to optimize the performance of the femtocell and cellular network as well.