Resource allocation in OFDMA underlay cognitive radio systems based on Ant Colony Optimization

This paper deals with dynamic resource allocation problem for OFDMA-based cognitive radio systems. The proposed solution is specifically tailored for a secondary base stations (SBS) transmitting to secondary users (SUs) over the same bands of the licensed primary users (PUs) in underlay fashion. The downlink transmission goodput is thereby maximized while keeping the interference on the PUs within a tolerable range. The NP-hard goodput maximization problem is tackled resorting to an efficient meta-heuristic algorithm based on Ant Colony Optimization (ACO) framework.