Analog antenna combining in multiuser OFDM systems: Beamforming design and power allocation

The goal of this paper consists in characterizing the capacity region of a broadcast system based on analog antenna combining and orthogonal frequency division multiplexing (OFDM). In particular, we consider the maximization of a weighted sum of the rates, which results in a highly non-convex optimization problem. The proposed iterative approach is based on the alternative optimization of the beamformers, and the power and subcarrier allocation. Finally, our experiments show that in most practical situations, the complexity of the optimal approaches (subcarrier sharing and power allocation) is not justified by the marginal gains in the capacity region.