Abstract: In order to accurately position the mobile user,most current localization algorithms based on RFID need anchor assist.It is usually difficult to find or deploy enough anchor nodes for accurate localization.To solve this problem,a location scheme of mobile users based on imprecise anchors was proposed.Firstly,a large number of tags with approxi-mate locations are used as anchor nodes to compute the users’ locations.It does not require any additional precise anchor nodes,thus effectively avoiding the significant deployment cost.Then,two time-efficient algorithms were proposed to accurately locate the moving user,i.e.,the category cardinality based protocol and the RSSI based protocol.Experimental results indicate that the solutions can accurately locate the mobile users in a real-time approach.The accuracy of the improved method improves over 30% than the base solution.

Key words: RFID,Location,Anchor,Tags,Accuracy