Linear Precoding and Stream Combining for Rate Splitting in Multiuser MIMO Systems

This letter develops practical linear precoding and stream combining techniques for rate-splitting (RS) in multiuser multiple-input multiple-output (MIMO) systems. We propose linear combining techniques based on the Min-Max, the maximum ratio and the minimum mean-square error criteria along with Regularized Block Diagonalization (RBD) precoders for RS-based multiuser multiple-antenna systems. An analysis of the sum rate performance is carried out, leading to closed-form expressions. Simulations show that the proposed combining schemes offer a significant sum rate performance gain over conventional linear precoding schemes.