MIMO Transmitter Optimization With Mean and Covariance Feedback for Low SNR

Multiple-input multiple-output system capacity can be improved when there is Channel State Information at the Transmitter (CSIT). This paper proposes a transmission optimization strategy that aims to maximize the mutual information using statistical CSIT. A second order approximation method is used to optimize the transmit covariance matrix. The proposed scheme is compared to the first order approximation, equal power allocation, and water-filling schemes. Beamforming strategy has been widely accepted as a tool to improve channel capacity of Multiple-Input Multiple-Output (MIMO) systems.