Adaptive Cross-layer Scheduling and Dynamic Subcarrier Allocation Algorithm Based on Service-differentiation in Multiuser OFDMA System

In this paper scheduling algorithm utilizing channel status information(CSI) and dynamic allocation algorithm of subcarrier and power is investigated in orthogonal frequency division multiplexing access (OFDMA) system. To this end, based on service differentiation we develop an adaptive cross-layer scheduling scheme combined with dynamic subcarrier allocation algorithm according to instantaneous traffic load condition over wireless Rayleigh fading channel. The algorithm is designed to grant higher priority to realtime traffic packet of voice and multimedia than data packet, and dynamically allocate subcarriers for data service according to the packet number of each user in the buffer queue with fairness guarantee. The simulation result shows that the proposed adaptive cross-layer scheduling and dynamic subcarrier allocation algorithm has shorter delay for realtime traffic and higher spectral efficiency than nonadaptive scheduling algorithm in Rayleigh fading channel.