Inductance Investigation of Screen-Printed Radio Frequency Identification Antennas

Abstract

Printed antennas fabricated using conductive ink printed on flexible substrate is low-cost and environmental friendly. The inductance and the quality factor are two important parameters for designing RFID antenna and were studied for the printed RFID antennas. The results show that the inductance is not only determined by the size of the designed RFID antenna but also related to the resistance of the printed antenna coils. The inductance increases with the increasing testing frequency, while the Q value decreases with the increasing testing frequency. The soft magnetic ink prepared with γ-Fe 2 O 3 was used to enhance the inductance of the printed antennas with printing technology. The inductance of the printed antenna with the magnetic core layer is increased by 5.7% at 13.56 MHz.