A novel beamforming scheme based on partial channel feedback in LS-MIMO systems

The tremendous performance of large-scale multiple input multiple output (LS-MIMO) systems can be achieved by applying linear beamforming schemes, such as maximum ratio transmission and zero forcing, in time-division duplex mode. However, it is prohibitive to acquire the instantaneous channel state information (CSI) at the transmitter in frequency-division duplex (FDD) systems. Thanks to the compact structure of the large-scale antenna array, beamforming can be constructed by exploiting the statistic CSI, such as spatial correlation, while the system performance is degraded. In this paper, to balance the system performance and feedback overhead in FDD LS-MIMO system, we propose a novel beamforming scheme based on both the spatial correlation and signal leakage (SCSL), where the channels from partial antennas to the users need fed back. Numerical results indicate that the proposed SCSL-based beamforming outperforms the spatial-correlation-based beamforming. Moreover, the effections of different antenna selection approaches on system performance are evaluated in detail.