Systems and methods to coordinate transmissions in distributed wireless systems via user clustering

A system for coordinating transmissions in a MU-MAS comprising:

• a plurality of wireless users;
• a plurality of base transceiver stations (BTSs) having a plurality of MU-MAS antennas for establishing multiple concurrent communication channels with the plurality of users;
• wherein either the BTSs and/or the wireless users measure link quality of the communication channels therebetween and use the link quality measurements to define a user cluster;
• the BTSs and/or the wireless users further measuring channel state information (CSI) between each user and each MU-MAS antenna within a defined user cluster and precoding data transmissions between the MU-MAS antennas within the user cluster and the users reachable by those MU-MAS antennas based on the measured CSI.