Multi-User Beamforming (MUBF) is a special technique of Multi-User MIMO( MU-MIMO). With MUBF, a base station has multiple antennas over which it simultaneously sends independent data streams to different users. This increases the aggregate network capacity.
MUBF theory states that the more antennas a base station has, the more users it can serve simultaneously. The number of antennas allows the network capacity to be adjusted to the number of users. Thus, network capacity grows with the number of antennas. This leads to the fact that with a sufficient number of station antennas, the network capacity can be scaled. However, there are limits to the MUBF theory, so that not any number of antennas can be used.