Sliding-Typed Communication Range Recognition Method for Indoor Position Estimation in Passive RFID Systems

RFID (Radio Frequency Identification) systems have become meaningful as a new identification source that is applicable in ubiquitous environments. Each RFID tag has a unique ID, and is attached to an object. A user reads the unique ID of an RFID tag with RFID readers and obtains the information of the object. One of the most important technologies that use the RFID system is the position estimation of RFID tags. The position estimation means to estimates the location of the object with the RFID tag. It is very useful to acquire the location information of RFID tag. If a user understands the position of the RFID tag, a new navigation system for persons in complex buildings. In this paper, we propose a new method for accurate indoor position estimation of passive RFID systems named as the Sliding-Typed CRR method. In this method, the position of an RFID tag is estimated by using S-CRR (Swift Communication Range Recognition) method. The proposed method is capable of accurate position estimation in any directions of RFID tags.