Robust SINR-constrained MISO downlink beamforming: when is semidefinite programming relaxation tight?

摘要: We consider the multiuser beamforming problem for a multi-input single-output downlink channel that takes into account errors in state information at transmitter side (CSIT). By modeling CSIT as elliptically bounded uncertainty regions, this can be formulated minimizing transmission power subject to worst-case signal-to-interference-plus-noise ratio constraints. Several methods have been proposed solve nonconvex optimization problem, but none guarantee global optimal solution. In article, we semidefinite relaxation (SDR) and prove SDR method actually solves robust optimality long bound is sufficiently small or when equipped with most two antennas. Numerical examples show approach significantly outperforms existing terms of average required consumption transmitter.