THE ELEVENTH IEEE SENSOR ARRAY AND MULTICHANNEL SIGNAL PROCESSING WORKSHOP (IEEE SAM2020)

Hybrid beamforming (HBF) structures have been recently proposed as one of the solutions to reduce cost and energy consumption of fully-digital multi-user MIMO systems in the millimeter-wave range. However, most of the initial references on HBF design assume frequency-flat single-carrier MIMO systems. Their extension to the frequency-selective multi-carrier MIMO-OFDM case is, in general, not a straightforward task, especially in partially-connected architectures. In this paper, we propose a new HBF design approach for multi-user massive MIMO-OFDM systems. Simulation results reveal that the proposed solution achieves a comparable performance to the benchmark methods in the fully-connected case, while significantly outperforming them in case of partially-connected architectures.

Hybrid beamforming; millimeter-wave; multi-user MIMO-OFDM