Dr. Mitradip Bhattacharjee’s [Department of Electrical Engineering and Computer Sciences] research group has developed a high-performance flexible sensing circular ring antenna designed for smart packaging applications. The antenna, which operates at approximately 3.9 GHz in the C-band, is fabricated on a polyethylene terephthalate (PET) substrate using a coplanar waveguide (CPW) feeding technique. It exhibits sensitivity to bending deformations, with frequency shifts and variations in return loss (S11) that allow for qualitative and quantitative strain measurements. The study records sensitivities of 8.25 and 7.37 for different longitudinal bending conditions and 16.8 and 15.22 for transverse and longitudinal packaging deformations. The antenna was successfully integrated into a smart chemical packaging system, detecting lateral and longitudinal bending deformations up to 1.5 cm with a resolution of 25 mm. The experimental results demonstrated that changes in S11 were more reliable for quantitative analysis, while frequency shifts could be used for qualitative detection. The paper also highlights the advantages of flexible antennas in IoT applications, wearable electronics, and structural health monitoring. The proposed antenna outperforms prior designs in terms of sensitivity and adaptability, making it a promising solution for real-world smart packaging and deformation monitoring applications. More details at https://ieeexplore.ieee.org/abstract/document/10740059
