Beam identification method, and related device and system in mimo beam forming communications system

Disclosed is a beam identification method in a MIMO beam forming communications system. The method comprises: a base station sending multiple beam training signals to a terminal, each beam training signal corresponding to one beam, and each beam covering a different direction; the terminal detecting the beam training signals, determining a selected beam according to a result of the detection, and feeding back information indicating the selected beam to the base station; the base station determining, according to the information indicating the selected beam fed back by the terminal, a beam used for sending data information. Also disclosed are a related beam identification device and system in a MIMO beam shaping communications system.