High efficiency of Low-cost Spiral Antennas for RFID, Fully Printed by an Inline Inkjet Process
Abstract
This paper describes the realization of 13,56MHz spiral antenna for RFID applications on A4 format substrate by an inline inkjet printing process. The first step consists on the printing of five loops of 20% nano-silver ink in a standard class 1 size. An intermediate inline drying step using variable frequency microwave allows the stacking of several silver layers. Else; an interconnecting bridge between the two sides of the spiral antenna is printed on the top of an insulating layer, also fabricated inline using a second printing head. After pasting an adequate chip, the RFID tag is read at a distance of 70mm and has a tuning frequency of 16.2MHz. The magnetic activation field of the tag is measured at 390mA/m by a standard test method and is similar to the performance achieved by commercial RFID tags fabricated by traditional technics.