Chunk-based and fairness-based resource allocation in multicast distributed MISO-OFDMA systems

The resource allocation problem for the downlink of Orthogonal Frequency Division Multiple Access (OFDMA) wireless multicast systems is investigated. It is assumed that the Base Station (BS) consists of multiple antennas in a Distributed Antenna System (DAS), whereas each user is equipped with a single antenna. The multicasting technology is able to support several groups of users with flexible Quality of Service (QoS) requirements. The general mathematical formulation is provided but achieving the optimal solution has a high computational cost. In our approach, the allocation unit is not the subcarrier, as in conventional OFDMA systems, but a set of contiguous subcarriers which is called “chunk”. For practical implementation, a suboptimal, but efficient algorithm is proposed in order to maximize the sum of the maximum attainable data rates of multicast groups of users, subject to total available power and proportional maximum attainable data rate constraints among multicast groups of users. Simulation and complexity analysis are provided to support the benefits of chunk-based resource allocation to multicast OFDMA DASs, supporting that the proposed algorithm can be applied to latest-generation wireless systems that provide QoS guarantees. Copyright c © 0000 John Wiley & Sons, Ltd.