Calibration method for periodic surface based chipless tags

Abstract

The aim of this paper is to introduce a novel calibration method for chipless tags. The proposed tag is based on a periodic impedance surface with an asymmetric unit cell geometry. The method relies on a differential encoding of amplitude or phase of the reflected signal. The unit cell of the tag comprises several concentric loops of rectangular shape which exhibits a different response when interrogated along two orthogonal planes of incidence. The novel calibration procedure is also preliminary verified experimentally for a simple single bit tag configuration. This work opens the way to a more practical implementation of chipless tags reading.