Performance comparison between two inter-cell interference coordination schemes for ofdma downlink systems

Considering an orthogonal frequency division multiple access (OFDMA) downlink system, signals originating from the same cell are orthogonal, while those from different cells interfere with each other. As a consequence, inter-cell interference becomes a major performance degradation factor, especially on cell borders. Recently, two inter-cell interference coordination schemes, namely partial frequency reuse (PFR) and soft frequency reuse (SFR), were suggested as the two most promising approaches for inter-cell interference mitigation in OFDMA systems. In this paper, the performances of PFR and SFR have been evaluated and compared based on the signal strength difference based user classification method, which is adopted in the Long Term Evolution standard. Compared with the universal frequency reuse system, our simulation results show that both PFR and SFR schemes provide a significant cell edge throughput gain; however, a loss in total cell throughput usually comes up. Furthermore, based on a well-defined data-rate fairness criterion, we show that PFR achieves a higher system capacity when compared to SFR.