“…Recently, distributed multiple-input multipleoutput (MIMO) or distributed antenna systems (DASs), which allow the exploration of various MIMO gains over spatially collaborative nodes, have been shown to be capable of significantly increasing system capacity [1][2][3][4]. Specifically, in distributed MIMO systems some neighboring nodes such as base stations (BSs), remote anten-na units (RAUs), or users in a particular geographic area can share their antennas in a cooperative manner and generate a virtual MIMO system [5][6][7][8].…”