Multi-User MIMO Linear Precoding with Grassmannian Codebook

In this paper, multi-user MIMO (MU-MIMO) linear precoding schemes with Grassmannian codebook for downlink transmission are proposed. The proposed MU-MIMO schemes extend the point-to-point single-user Grassmannian precoding to point-to-multipoint multi-user Grassmannian precoding. We proposed two MU-MIMO schemes with the Grassmannian codebook. One scheme assumes the perfect channel information at the base station and the other scheme is under the limited feedback. These MU-MIMO linear precoding schemes with Grassmannian codebook provide significant system capacity enhancement compared with the single user MIMO (SU-MIMO) system. The results also show the performance gap between perfect channel information and limited feedback.