An Anti-Collision protocol of RFID Based on Divide and Conquer Algorithm

Radio frequency identification (RFID) system is a wireless automatic identification mechanism. Now, it is widely applied in supply chain management, supermarket checkout process, public transportation, animal identification, the localization and tracking of objects and people, and toll ways. The tag collisions in RFID system is an unavoidable problem. The number of collision in previous tag anticollision protocol algorithms is direct proportion to the number of tags. In this paper, we propose a new anticollision protocol algorithm based on divide and conquer for RFID system. Our algorithm divides the successive collision bits into several two bits groups, use these groups to search which the collision group is and where the collision occurring, and identify all tags finally. From the experiment results, the number of tag collision in our algorithm only depends on the length of tags, and is independent of the number of tags. So, the time complexity our algorithm is ) 1 ( Ο Big .