Abstract: Against the tag collision problem in Radio Frequency Identification（RFID） system，this paper proposes a new RFID anti-collision algorithm based on bit-detecting，and the procedure of the algorithm is introduced in detail.By setting a counter in the tag，the closest node tags at the tree can be activated when backing research.The reader send command only need detect the certain bit is “0” or “1” of the tag’s ID and the tags transmit the part of ID below the detected bit，which can reduce the quantity of the data communication efficiently between tags and reader.Finally，the results of simulation also show that the new algorithm has better performance in comparison with the existed binary algorithm，and can improve the speed of the tag identification obviously.

Key words: Radio Frequency Identification（RFID）, tag anti-collision, binary-tree algorithm, bit-detecting

摘要： 针对RFID（radio frequency identification）系统中标签的碰撞问题，提出了一种基于二进制树位检测的RFID标签防碰撞算法，设计了算法实现的详细流程。该算法通过在标签内设置一个计数器，实现后退搜索时相邻树节点标签的激活。读写器发送命令只需检测标签ID的某个比特的电平，标签返回检测位以下的部分ID，可以大幅减少读写器与标签之间的通信量。仿真结果表明此算法比现有的二进制树算法更具优势，能显著提高标签识别的速度。

关键词: 射频识别, 标签防碰撞, 二进制树算法, 位检测