【作者】 李庆亮； 王资凯； 韩韬；

【Author】 LI Qing-liang WANG Zi-kai HAN Tao Department of Instrument Science and Engineering,Shanghai Jiaotong University,Shanghai,200240

【机构】 上海交通大学电子信息与电气工程学院；

【摘要】 声表面波射频标签(SAW-RFID)的多目标辨识是这类识别技术实用化的关键.本文首先综述了这方面的国内外最新研究进展.提出了一种基于 WALSH 变换的匹配门限滤波方法,即在大容量编码的 SAW-RFID 标签状态中, 预先依据 Walsh 滤波门限选择出可利用的标签作为正式使用的编码标签.当在阅读器天线辐射范围内有多个标签时, 接收的多个标签的回波信号的和虽然在时域上没法分辨,但是通过对标签综合信号进行 Walsh 变换到序域上,并按照给定的序率门限进行滤波,再与标签编码数据库进行编码匹配,最后经过 Walsh 反变换,将会得到综合信号中的各自的标签信息.实验数据证明这种方法是实用、可行的.更多还原

【Abstract】 The multi-targets identification in surface acoustic wave(SAW)based radio frequency identification(RFID)is one of key techniques in RFID.This paper overviews the state-of-the-arts of the anti-collision methods.A new anti-collision algorithm based on the Walsh threshold matched-filtering has been presented.When the received signal comprises multi-tags,although they cannot be distinguished by time domain separation directly,the collided tags have special features in Walsh Transform domain.The selection of threshold and the influence to coding capacity are discussed.The experimental results manifest the validity of this algorithm.更多还原