A New Intelligent Multi-tree RFID Anti-collision Algorithm

In the radio frequency identification system, a reader may communicate simultaneously with multiple tags, thus there exist the problems of collisions. So anti-collision is the key to resolve data conflicts and it affects the performance of RFID system to a great extent. In this paper, based on the existing binary-tree search a great extent, a new intelligent multi-tree anti-collision algorithm is proposed. The algorithm proposed in this paper uses Manchester code which can accurately identify the position of collision. And by calculating the impact factor, we can estimate the number of tags of the branch so as to adjusting the number of searching tree intelligently. Algorithm chooses the quad-tree search algorithm on the case of more tags in the branch, otherwise selects the binary-tree search algorithm. According to the simulation results, the algorithm proposed by this paper has overcome the disadvantages of the original binary-tree algorithm and greatly reduced the collision slots and idle slots in the searching process, effectively improving the throughput rate and shortens the reading time, and having a certain availability.