Dynamic Subcarrier and Bit Allocation for Throughput Maximization in Multiuser Ofdm Systems Using Ant Colony Optimal Algorithm

In this paper, an efficient dynamic resource allocation scheme for multiuser orthogonal frequency division multiplexing (OFDM) systems is investigated. There have been many researches to maximize total system throughput with only limited transmission power. In addition to the limited power, we add required minimum transmission bits for each user as another constraint for the quality of service (QoS) requirement. Greedy based algorithms are usually considered as methods that maximize total system throughput, but our algorithm outperforms the greedy based algorithm by using one of the heuristic algorithms called ant colony algorithm (ACA). The proposed algorithm maximizes the overall system throughput under the given total transmission power while satisfying QoS requirements such as required bit error rate (BER) and minimum transmission bits for each user. Also, it is shown that the proposed algorithm provides better performance in terms of system outage probability, throughput fairness per user, and subcarrier availability through numerical simulation results.