Hybrid Beamforming with Blockwise Beam Selection for mmWave Beamspace MIMO systems

Hybrid beamforming is a signal processing technique composed of multiple components that is of significant importance in reducing transceiver costs and improving spectral efficiency in the context of highly directive wireless communications. Conventional hybrid beamforming leads to considerable baseband computation and suboptimal amplitude factor due to the use of extensive antenna arrays. Hence, we propose a blockwise beam selection (BBS) algorithm to achieve a low-dimensional hybrid beamformer and minimize the computation of baseband processing in mmWave beamspace multiple-input multiple-output lens antenna array systems. In this paper, we first present a block-wise design of a transmitting analog beamformer. In order to achieve a low-dimensional hybrid beamformer, we then apply the proposed BBS algorithm that significantly reduces the dimensions of the baseband processor and enhances the system performance. Finally, the simulation results validate the superiority of the proposed BBS algorithm compared to its traditional non-blockwise beam selection counterparts.