Wideband hybrid precoder for mmWave multiuser MIMO OFDM communications

Using millimeter wave (mmWave) transmission for massive multiple input output (MIMO) system can improve performance and effectively reduce the size of antennas array. However, A wideband beamformer design is needed to take advantage this channel. In paper, a downlink multi-user MIMO orthogonal frequency division multiplexing (MIMO OFDM) mmWave communications proposed. Each subcarrier channel be approximated as narrowband clustered channel, so precoder applied each subchannel. The hybrid implemented in manner digital obtained subcarrier, whilst analog common all subcarriers. modified “joint spatial division/multiplexing” (JSDM) scheme used precoder, where user equipped with more than one antenna. based on second order statistics overhead information need process fed back baseband instantaneous state (CSI). Following approach Kronecker model, iteration between beamformers at both end link avoided. Finally testing using various numbers base station.