A network control device. A wireless communications module receives a plurality of first signals each including information regarding a preferred transmitting beam in a first beam level determined by a communications apparatus. A controller selects a group of communications apparatuses to join a 1-to-many beam training according to the received first signals and selects one or more transmitting beams in a second beam level to be trained. The communications apparatuses in the group have the same preferred transmitting beam in the first beam level and the transmitting beam(s) in the second beam level associates with the preferred transmitting beam in the first beam level. The wireless communications module further uses the transmitting beam(s) in turn to transmit signals to perform the 1-to-many beam training for training the transmitting beam(s) in the second beam level among the group of communications apparatuses at the same time.