同义词
1)small branch exchange,小型电话交换机2)unit automatic exchange,内部自动电话交换机，小型自动电话交换台3)UAX Unit Automatic Exchange,(电话)自动交换装置，小型自动电话交换机4)centralized private branch exchange,集中式电话小交换机5)private branch exchange(PBX),专用电话小交换总机6)telephone private branch exchange,用户电话小交换机
