Dual methods for channel- and QoS-aware resource allocation in MIMO-OFDMA networks

This work addresses the application of the cross-layer paradigm to the design of efficient resource allocation algorithms for the downlink of a MIMO-OFDMA system with a physical layer employing optimal single-stream/single-user linear precoding. Mathematical programming tools are used to solve the problem of weighted throughput maximization using both channel state information from the physical layer and queue state information supplied by the data link control layer. Due to the complex combinatorial nature of the problem, low-complexity Lagrange decomposition methods combined with subgradient projection algorithms are used to find a solution in the dual domain. The analytical framework proposed in this paper is used to assess the multiuser capacity, packet delay performance and fairness for different channel- and/or QoS-aware resource allocation algorithms proposed in the literature and different MIMO channel configurations.