User Grouping of Two-Stage MU-MIMO Precoding for Clustered User Geometry

This letter investigates how user grouping, more specifically group partitioning, affects the sum-rate performance of a two-stage multiuser MIMO precoding scheme referred to as joint spatial division and multiplexing (JSDM). Taking a clustered user geometry model into account, we propose a new criterion for user grouping to noticeably improve the sum-rate performance of JSDM. Numerical results confirm that the user grouping based on the proposed criterion yields substantial performance enhancement.