Abstract:This paper addresses adaptive resource allocation for OFDMA downlinks. A sub-optimal two-step sub-carrier allocation scheme is proposed to minimize the outage probability for a total transmit power budget. A characteristic of bandwidth and sub-carrier allocation is analyzed, and a two-step sub-carrier allocation scheme is proposed, which distributes bandwidth and sub-carriers among users based on available resource, QoS requirements and channel state information. Simulation results demonstrate that the proposed algorithms can achieve low outage probability while meet the total power budget.