Direction non-sensitive chipless RFID tag using retro-reflective UWB array

摘要

In this work, a chipless tag antenna employing retro-reflective array for ultrawideband radio-frequency identification (UWB-RFID) application is demonstrated. Different from conventional RFID tags, by using retro-reflective antenna, the proposed antenna is not sensitive to its relative direction to the reader, leading to longer reading range in practice. Folded slots are etched in the transmission line connecting the UWB array to work as band-reject filters. The absence and presence of slots of different lengths are used to carry the bit information. An example of four bits RFID tag is illustrated in the work, showing its direction non-sensitive characteristic. It is possible to integrate more bits in the tag antenna.