Adaptive resource allocation for single-cell downlink orthogonal frequency division multiple access systems

We propose a cross-layer resource allocation strategy, called joint bit and power allocation (JBPA), for adaptive modulation and coding (AMC)-based orthogonal frequency division multiple access (OFDMA) systems in which both coding rates and modulation order can be changed. The objective of this strategy is to maximise the system throughput as a function of the bit error rate and spectral efficiency. The JBPA strategy takes into account the total transmission power constraints and the related channel state information in order to select the suitable modulation and coding scheme for each sub-channel. The performance in terms of average throughput of the proposed strategy is examined and compared with those of the resource allocation approaches for AMC-OFDMA systems in the context of WiMAX technology. The simulation results show that the proposed JBPA strategy significantly outperforms the other approaches.