Corrections to and Comments on “Throughput and Optimal Threshold for FFR Schemes in OFDMA Cellular Networks” [Aug 12 2776-2785]

In a recent paper published in these Transactions, Xu et al. (see ibid., vol. 11, no. 8, pp. 2776-2785, Aug. 2012) proposed an analytical framework to calculate the throughput and optimal threshold for fractional frequency reuse (FFR) schemes in orthogonal frequency division multiple access (OFDMA) cellular networks. This correspondence points out a problem in the original derivation of Xu et al. and how this affects the claimed performance of the maximum signal-to-interference-plus-noise ratio (MSINR) scheduling rule. A fix to this problem is presented in this work, which turns out to extend the applicability of the analysis beyond the case studied by Xu et al. and at the same time shows how the performance of the round robin (RR) scheduling rule can be obtained as a special case of the MSINR scheduler. Monte Carlo simulation results demonstrate the validity and merits of our proposed approach.