An RFID reading apparatus includes a frame. The RFID reading apparatus also includes an RFID interrogator, coupled to the frame, for triggering transponders in picked cases and receiving and decoding replies. The RFID reading apparatus further includes at least one vertically movable antenna mount coupled to the frame, at least one antenna mounted to the antenna mount and coupled to the interrogator, and at least one object sensor adjacent to at least one antenna. The RFID reading apparatus also includes a control unit coupled to the interrogator for initiating interrogation of transponders and accepting decoded replies, to the antenna mount for controlling the level of the antenna mounted on the mount, and to the object sensor for detecting the presence of cases adjacent to the object sensor.