Novel size-reduced unit cells for uniplanar chipless RFID tags

The paper introduces the two new size-reduced unit cells/scatterers in the form of uniplanar resonators for application in frequency spectrum-based uniplanar chipless RFID tags. They are derived from U-folded dipole loaded by either meander line inductor or interdigital capacitor. Radar cross section, and resonant frequency has been evaluated by EM simulation and S-parameters have been measured and calculated when scatterers have been placed in parallel-plate waveguide. The results clearly show the trade-off between size-reduction and radar cross section proportional to read range of the proposed configurations. Their potential lies in the development of new smaller uniplanar chipless tags with higher information density.