US Patent 7382990 Image forming apparatus

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.