RFID Tag Anticollision Scheme Using Modular Arithmetic

In order to solve the problem of multiple tag collision in RFID system, a RFID tag anticollision scheme using modular arithmetic is proposed in this paper. Firstly, the number of tag is estimated, and then modular arithmetic is taken on the tag's ID bit-by-bit. The tags with the same remainder are classified into a group. After K times' modular arithmetic, all tags are divided into 2K groups. The tags in each group have few collision bits, and the group ID is the slot that tags will be read. Then, tags sent their ID according to the corresponding slot. Collision tags can be further identified with binary tree algorithm. The efficiency of tag identification is greatly improved using this scheme. It is suitable for identifying massive tags in RFID system.