Metamaterial transmission lines for wireless communications, sensing and RFID

Metamaterial transmission lines are artificial lines implemented by loading a host (ordinary) line with reactive elements. Due to the presence of these additional elements, these lines exhibit further design flexibility, as compared to ordinary lines. Thus, it is possible the design of microwave components with high performance, with novel functionalities and/or with reduced size, on the basis of the controllability of the characteristic impedance and dispersion of the constitutive lines (impedance and dispersion engineering). In this work, it is shown that metamaterial transmission lines can be applied to many different scenarios within wireless communications, sensing, and radiofrequency identification (RFID), and some recent applications are pointed out. This includes multiband devices and antennas, novel sensors based on symmetry properties, and novel tag concepts for UHF-RFID and chipless RFID.