Coordinated Sub-Carrier and Band Hopping in OFDMA based Systems

We propose a novel algorithm to allocate heterogeneous users in a wideband orthogonal frequency division multiple access (OFDMA) system. The heterogeneity among users originate from different channel statistics experienced by the users. The total available spectrum is divided into a number of bands equal to the number of groups. For efficient time-frequency resource allocation, sub-carrier hopping and band hopping is simultaneously used in this novel multiple access scheme. Under some constraints, sub-carriers can also be assigned to different users based on known channel characteristics using dynamic sub-carrier allocation. Sub-carrier and band hopping are used for mitigating the frequency selectivity of the wireless channel and for minimizing and avoiding interference in the system. The novelty comes when users are grouped based on some pre-defined criteria and they are hopped on sub-carriers as well as on bands. The proposed scheme is equally applicable to both downlink and uplink.