Testing and modeling the performance of stretchable screen printed UHF RFID tag under strain

We characterize a passive UHF RFID tag based on a stretchable dipole antenna which is screen printed on ultra-thin polyurethane substrate with silver ink. Our results show that the change in the conductor properties due to strain is large enough to modify the electromagnetic properties of the antenna notably, yet small enough so that the tag retains high performance even under 20-% strain. By comparing the simulated and measured results, we attest a strain-dependent sheet resistance model.