The impact of cross-layer ressource management MAC-PHY in wireless OFDMA networks

We propose a cross-layer algorithm for the down link multiuser orthogonal frequency division multiplexing (OFDM) system. The goal of this algorithm is to ensure fairness among users while preserving the full system throughput as close as possible to the system throughput upper bound. For this, a function is formulated to designate which packet will be scheduled at any given time. This function takes into account the parameter from the physical layer and MAC layer. At the physical layer, a user must be well served without degrading the other users. The proposed cross layer algorithm requires the knowledge of channels state information and the state of the queues. Simulation results show that the proposed scheme of resource allocation algorithm provides a near-optimal performance for the average system throughput and provides a good fairness among users, while requiring a relatively low complexity.