An image forming apparatus includes at least two radio frequency
identification (RFID) tags, an interrogator activating the RFID tags and
sequentially receives tag information from the RFID tags according to the
priority orders of the RFID tags, and a controller controlling the
operation of the interrogator. Tag information of a plurality of RFID
tags can be received by a single reader (interrogator). In other words,
radio communication can be achieved without a plurality of readers,
thereby reducing the material costs.