Institute of Electrical & Electronic Engineers
Due to the NP-hard complexity on sub-channel (subcarrier or sub-band) allocation and power assignment (or rate control) for Orthogonal Frequency-Division Multiple Access (OFDMA) systems, recently, various heuristic resource allocation algorithms minimizing power consumption with polynomial complexity have been studied. Different criteria have been employed in different algorithms to minimize the network power. A Bandwidth Assignment Based on Signal-to-noise-ratio (BABS) Amplitude-Craving-Greedy (ACG), a BABS Rate-Craving-Greedy (RCG), and a SUccesSive user Integration (SUSI) algorithms has been proposed. Sub-channels are greedily assigned to a user who yields a maximum rate and a maximum effective channel gain in RCG or ACG.