IEEE TRANSACTIONS ON MOBILE COMPUTING 1 Anti-collision Protocols for Single-Reader RFID Systems: Temporal Analysis and Optimization

Abstract—One of the major challenges in the use of Radio Frequency-based IDentification (RFID) on a large scale is the ability to read a large number of tags quickly. Central to solving this problem is resolving collisions that occur when multiple tags reply to the query of a reader. To this purpose several MAC protocols for passive RFID systems have been proposed. These typically build on traditional MAC schemes such as aloha and tree based protocols. In this paper we propose a new performance metric by which to judge these anti-collision protocols: time system efficiency. This metric provides a direct measure of the time taken to read a group of tags. We then evaluate a set of well-known RFID MAC protocols in light of this metric. Based on the insights gained we propose a new anti-collision protocol and show that it significantly outperforms previously proposed mechanisms. Index Terms—RFID, passive tags, single reader, anti-collision, MAC protocols.