PAR-aware multi-user precoder for the large-scale MIMO-OFDM downlink

We consider an orthogonal frequency-division multiplexing (OFDM)-based downlink transmission scheme for large-scale multi-user (MU) multiple-input multiple-output (MIMO) wireless systems. In order to transmit signals with low peak-to-average (power) ratio (PAR), we propose to exploit the massive degrees-of-freedom available in large-scale MU-MIMO-OFDM systems. Specifically, we jointly perform MU precoding, OFDM modulation, and PAR reduction by solving a convex optimization problem at the base station. Numerical results demonstrate tremendous PAR-reduction capabilities of the proposed method, which eventually enables us to use low-cost RF components for the large-scale MU-MIMO-OFDM downlink.