%0 Journal Article
%T Theory and measurement for mutual coupling effect of ultra high frequency radio-frequency identification in dense environments<br>标签密集环境下天线互偶效应研究
%A Zuo Lei
%A He Yi-Gang
%A Li Bing
%A Zhu Yan-Qing
%A Fang Ge-Feng
%A <br>佐磊
%A 何怡刚
%A 李兵
%A 朱彦卿
%A 方葛丰
%J 物理学报
%D 2013
%I 
%X The close displacement of ultra high frequency radio-frequency identification (UHF RFID) tags can be considered as an electromagnetically interconnected system which causes the mutual coupling effect among antennas of tags, thereby resulting in change in impedance matching condition. Based on the principles of RFID technology and Friis propagation equation, a link budget model of UHF RFID is provided which consists of one reader and one tag. Expressions of mutual impedance in dense environments are derived by using a two-port network. Utilizing the parameters of power transmission coefficient and modulation factor, the variation of system performance is discussed in theory and tested by three experiments which are conducted in open indoor environment. The measurement results show that the change rate of minimum power transmitted by the reader antenna is in a range from -7% to 11.6% for two-tag scene and from -10% to 12.5% for two-plane arrangement.
%K radio frequency identification
%K dense environments
%K mutual coupling
%K mutual impedance<br>射频识别
%K 密集环境
%K 互偶效应
%K 互阻抗
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=6E709DC38FA1D09A4B578DD0906875B5B44D4D294832BB8E&cid=47EA7CFDDEBB28E0&jid=29DF2CB55EF687E7EFA80DFD4B978260&aid=624C45FD0BDC9CE08232807B79992783&yid=FF7AA908D58E97FA&iid=E158A972A605785F&journal_id=1000-3290&journal_name=物理学报&referenced_num=0&reference_num=0