动态帧时隙的二进制树RFID防碰撞算法研究

Research on Dynamic Framed Binary Tree Anti-collision Algorithm for RFID System

为解决无线射频识别(Radio Frequency Identification,RFID)系统多标签碰撞问题,在分析动态帧时隙ALOHA算法和二进制搜索树算法基础上,提出一种基于动态帧时隙的二进制树RFID防碰撞算法(Dynamic Framed Binary Tree,DFBT)。采用Vogt算法预先估计待识别标签总数,利用动态帧时隙ALOHA算法对标签进行识别,阅读器将未识别的标签提取出来进行最高碰撞位的判断,根据最高碰撞位的情况结合二进制搜索树算法进行碰撞标签分裂。仿真结果表明:DFBT算法提高了识别效率和稳定性,减少了总时隙数,降低了标签成本。当标签数目达到1 000左右,算法识别效率可以达到64%左右,比动态帧时隙ALOHA算法和后退式二进制搜索树算法分别提高了210%和30%。

Based on dynamic frame-slotted ALOHA algorithm and binary search tree algorithm, a dynamic framed binary tree （DFBT） anti-collision algorithm is presented to solve the problem of multi-tag collision in radio frequency identification （RFID）. Vogt algorithm is adopted to estimate tags number, then the dynamic frame-slotted ALOHA （DFSA） algorithm is used to identify tags, and the unidentified tags are extracted and the highest collision bit is judged by readers. The highest collision tags are grouped by the collision bit within the binary search tree （BST） algorithm. Simulation results show that the DFBT algorithm can improve the identification efficiency and stability which reduces the total time slots and the cost. When the tags number is about 1000, identification efficiency of the DFBT algorithm is about 64%. Compared with the DFSA algorithm and the regressive-style binary search tree （RBST） algorithm, the proposed algorithm enhances the identification efficiency by 210% and 30% respectively.