Base station: the base station subsystem mainly includes two types of equipment: base station transceiver (BTS) and base station controller (BSC).
The equipment in the communication room is BSC.
A radio transceiver that transmits information between a mobile communication switching center and a mobile phone terminal in a certain radio coverage area.
The tower antenna outside communication room is BTS. The main function is to provide wireless coverage, that is realize wireless signal transmission between wired communication network and wireless terminal.