On a compact printable dual-polarized chipless RFID tag using slot length variation encoding technique for barcode replacement

A novel compact printable dual-polarized (DP) chipless RFID tag is presented in this paper with simulation and measurement results. First, vertically (V) and horizontally (H) polarized `U' shaped slot resonators are etched from two metallic patches to reuse the same frequency band in both V and H polarizations, which doubled the encoding capacity within a fixed bandwidth. Next, slot length variation encoding technique is added to reduce the size of the tag by 50%. After that, a 16-bit proof of concept DP tag is developed that achieved 16 bit/cm² data density, which is the highest among the reported works to date. Therefore, the proposed single sided easily printable tag possesses a good prospect due to its higher encoding capacity and data density, and can replace barcode in item level tagging of low cost and printable items, where tags will be required in trillions.