A Novel Flying Bird Dipole Resonator for Dual-Mode RFID-Based Temperature Sensing

This paper presents the design and analysis of a novel Flying Bird Dipole (FBD) resonator that functions as a dual-mode temperature sensor, operable in both chipped and chipless Radio Frequency Identification (RFID) domains. The proposed sensor utilizes bi-metallic arms made of zinc and copper, exploiting their differential thermal expansion properties for accurate and cost-effective temperature sensing. The sensing mechanism of the resonator is demonstrated through simulated and experimental analyses, which reveal its ability to detect temperature variations by monitoring changes in reflection coefficient amplitude and phase. The chipless version exhibits higher sensitivity of 0.098 dB/°C and greater flexibility, operating across the Ultra-Wide Band (UWB) spectrum, while the chipped version achieves a sensitivity of 0.053 dBm/°C. Experimental studies further confirm the chipless sensor's adaptability to a wide frequency range and increased temperature tolerance. The results indicate that the proposed FBD resonator holds significant promise for industrial applications, including food manufacturing, cold chain, and pharmaceutical storage. This work establishes the FBD resonator as a scalable, low-cost solution that addresses the limitations of existing RFID-based sensing technologies.