A New Scheme with Controllable Capacity and Fairness for OFDMA Downlink Resource Allocation

A new scheme is proposed in this paper for OFDMA (orthogonal frequency division multiple access) downlink resource allocation. It seeks to maximize the total system capacity subject to constraints on total available power, BER and rate proportions. Future communication systems should take both capacity and fairness into account together. Therefore, the new scheme has a novel step to rearrange the subcarriers among users with least capacity loss and most fairness gain to achieve a certain tradeoff between enhanced rate (Hui and Zhou, 2006) and proportional fairness (Shen et al., 2003). This tradeoff can be easily controlled by the introduced tradeoff-factor (TF). Simulation results show that this new capacity and fairness controllable scheme may be suitable for future quality of service (QoS) adjustable OFDMA systems.