A Novel Reconfigurable Chipless RFID Tag Based on Notch Filter

A novel reconfigurable chipless RFID tag to enhance encoding capacity is proposed in this paper. The entire transmission network includes four non-interacting ports that are independent separately. The reconfigurability can be realized by combining different ports to get different encoding results. To increase the anti-interference capability of the tag, a method of cross-combination for unit coders is proposed according to the spacing distances of the unit coders. The encoding ability of about 8-bit information can be obtained by using the compact tag structure with a dimension of 70×70 mm2 and the encoding capacity can be increased by increasing the number of unit coders. Code “1” or “0” is defined by arranging the appearance or disappearance of a unit coder. Typical encoding examples are presented and the simulation results match well with the measurement results, demonstrating the effectiveness of the proposed tag. The proposed tag can be used for structural health monitoring with the advantages of battery-free, large information capacity, and flexible usage.