Iterative scheduling for cell-edge in multi-cell MU-MIMO

The paper addresses the iterative joint scheduling algorithms for cooperative multi-cell multi-user (MU) multiple-input multiple-output (MIMO) transmission scheme with the sum rate maximization objective for the cell-edge users. We propose an iterative scheduling scheme which selects the users in each coordinating base station (BS) by considering the mutual interference among the chosen sets. At first, a static user selection (S-US) scheme is discussed, which performs the user selection in a centralized way from the users associated with each BS. Following that, we study the performance of the scheduling scheme, namely coordinated user selection (C-US) scheme, which performs scheduling of users and the associated BS so as to maximize the sum rate. In the C-US scheme, the users are linked dynamically to a BS by the C-US algorithm. The sum rate performance is discussed for the proposed algorithms with the precoders designed using either with zero-forcing (ZF) beamforming (BF) or weighted minimum mean squared error (W-MMSE) scheme.