“物联网技术导论”课程专题报告 专题1：RFID的识别与估算机制 谢磊教授 南京大学计算机科学与技术系
专题1：RFID的识别与估算机制 谢磊 教授 南京大学计算机科学与技术系 “物联网技术导论”课程专题报告
主要内容： 一、RFD的基本通信原理 二、基于时隙ALOHA的标签识别机制 三、RFID标签估算机制(Estimation) 四、开放性问题(Open Problem) 五、参考文献
二、基于时隙ALOHA的标签识别机制 主要内容： 五、参考文献 三、RFID标签估算机制（Estimation） 一、RFID的基本通信原理 四、开放性问题(Open Problem）
RFD的基本通信原理-1 Far-Field Propagation and Backscatter Principle Distance r o" Matching Network Reader Za TAG P4 P3 Reader antenna Tag antenna gain Gt gain Gr Fig.1.Far-Field Propagation for RFID system
RFID的基本通信原理-1 • Far-Field Propagation and Backscatter Principle
RFD的基本通信原理-2 Far-Field Propagation and Backscatter Principle We denote the down-link communication from the reader to a tag as the forward channel,and denote the up-link communication from a tag to the reader as the reverse channel. forward channel Distance r P2 Matching Network Reader Za TAG Reader antenna Tag antenna gain Gt gain Gr reverse channel Fig.1.Far-Field Propagation for RFID system
RFID的基本通信原理-2 • Far-Field Propagation and Backscatter Principle – We denote the down-link communication from the reader to a tag as the forward channel, and denote the up-link communication from a tag to the reader as the reverse channel. forward channel reverse channel
RFD的基本通信原理-3 Far-Field Propagation and Backscatter Principle For successful reading of a passive tag with the backscatter scheme, there are two thresholds to meet the physical requirements.The first is the tag power (sensitivity)threshold,Pts.It is the minimum received power necessary to turn on an RFID chip.The second is the reader sensitivity threshold,Prs.It is the minimum level of the tag signal that the reader can detect and resolve. Distance r Matching Network Reader Za 9 Prs Pt灯 TAG P4 Reader antenna Tag antenna gain Gt gain Gr Fig.1.Far-Field Propagation for RFID system
RFID的基本通信原理-3 • Far-Field Propagation and Backscatter Principle – For successful reading of a passive tag with the backscatter scheme, there are two thresholds to meet the physical requirements. The first is the tag power (sensitivity) threshold, Pts. It is the minimum received power necessary to turn on an RFID chip. The second is the reader sensitivity threshold, Prs. It is the minimum level of the tag signal that the reader can detect and resolve. Pts Prs