Low Complexity Robust Coordinated Beamforming in Multicell Network with Channel Uncertainties
Paper ID : 1750-IST
1Mohammad Hossein Akbari *, 2Vahid Tabatabavakili
1Iran University of Science & Technology (IUST)
2University of science and Technology
Multicell coordinated beamforming, where multiple base stations (BSs) collaborate with each other in the beam-vectors design for mitigating the intercell interference (ICI), has been a subject drawing great attention recently. With perfect channel information available at the base stations, we ﬁrst present a novel fast converging algorithm that solves the weighted sum rate maximization (WSRM) problem. Then, the assumption is relaxed to the case where the error vectors in the channel estimates are assumed to lie in an uncertainty set bounded by an ellipsoid. We propose a novel linear beamforming across a set of coordinated cells only with limiting backhaul signalling. Resource allocation (i.e. precoding and power control) is formulated as an optimization problem with objective function of signal-to-interference-plus-noise ratios (SINRs) in order to maximize the instantaneous weighted sum-rate subject to power constraints. Although the primal problem is nonconvex and difficult to be optimally solved, an iterative algorithm is presented based on the Karush-Kuhn-Tucker (KKT) condition. We evaluate robust beam design through simulation and observe that the proposed strategies has sufficient robust in front of channel uncertainties.