Resource Allocation in Multiuser OFDMA System: Feasibility and Optimization Study

This paper studies resource allocation problem in downlink multiuser orthogonal frequency division multiple access (OFDMA) system. The problem is formulated as sum-rate (cell throughput) maximization problem with strict data rate constraints imposed by the users and peak power constraint by the base station. We discuss the feasibility of the problem and propose two algorithms when the feasibility conditions are met. In the first algorithm subcarrier and power allocation decisions are made by jointly considering all the constraints. In the second algorithm subcarrier allocation decisions are based on data rate constraints and transmit power constraint is achieved on the allocated subcarrier set. The second algorithm although sub-optimal has almost identical performance compared to the first algorithm. The reduction in complexity is huge compared to the first algorithm.