摘要： 针对射频识别(RFID)系统中标签数量未知的情况,采用传统ALOHA 算法进行标签估计,在标签数量较大而初始帧长度较小造成估计误差较大时,初始帧长度为固定值,通过改变响应标签数量的方式,达到准确估计标签的目的。研究标签鲁棒估计算法和随机前缀查找树(PRQT)防碰撞算法,在此基础上提出基于鲁棒估计的自适应最大前缀查找树(PMQT)防碰撞算法。理论分析和仿真结果表明,该算法系统效率可达50% 以上。PMQT 算法 比PRQT 算系统效率提高18% ~30% ,对标签估计偏差具有较高的鲁棒性。

关键词: 射频识别, 标签识别, 标签估计, 防碰撞算法, 鲁棒性, 自适应

Abstract: In the research of Radio Frequency Identification (RFID) system,when the number of unknown tags is estimated by using the traditional ALOHA algorithm,the large number of tags and the smaller initial frame length will cause large error. Using the initial fixed length of the frame,reader changes the response method to achieve an accurate tag number estimation. This paper studies a robust tag estimation method and the Prefix Randomized Query Tree(PRQT) algorithm,and then proposes Prefix Maximized Query Tree(PMQT) tag anti-collision protocol. The theoretic analysis shows that the system efficiency is more than 50% . The simulation result demonstrates that PMQT outperforms PRQT by about 18% ~30% with respect to the system efficiency. In addition,PMQT algorithm has tolerance to the inaccuracy of tag estimation.

Key words: Radio Frequency Identification ( RFID ), tag identification, tag estimation, anti-collision algorithm, robustness;self-adaptive

中图分类号: 

• TN911