DefinePK

Abstract

This paper addresses the need for low-cost, tamper-evident identification tag within regulated supply chains by advancing a chipless radio-frequency identification approach that encodes information in the scattering spectrum of printable resonant structures. The proposed tag comprises eight concentric hexagram resonators patterned in conductive ink on a polyethylene terephthalate substrate, forming a 10 × 10 mm² label that yields an unambiguous 8-bit signature via eight well-separated attenuation minima in the radar cross-section spectrum across 7–20 GHz. With the help of commercially available state-of-the-art full-wave electromagentic simulation software, this study characterizes the normal and tampered state produced by the electronic equivalent of physical tampering of the tag. Tampering suppresses specific modes and shifts the remaining resonances—reducing the code to six notches displaced toward higher frequencies—thus enabling simple decision rules based on notch count, depth, and frequency shift to detect compromise. The results demonstrate a pathway from laboratory concepts to scalable, passive, and fully-printable tamper evident packaging with built-in chipless RFID tag structures that can unify identification with integrity monitoring in pharmaceuticals, food, and high-value parts.