Achievable Rate Regions for OFDMA with Link Adaptation

In this paper, we discuss the achievable rate regions for the uplink of an OFDMA system. The capacity region is computed for realistic channel models, exploiting a recent generalization of the well-known iterative water-filling algorithm. We then invoke the important constraint of exclusive user allocation per subchannel and approximate the corresponding capacity region. Apart from considering the capacity regions, we also compute the rate regions which can be achieved with the link adaptation scheme of a 4G system proposal and consider a low-complexity alternative. Finally, we outline the impact of some popular scheduling policies on the achieved rates.