UHF RFID Tag Antenna Performance Near Metallic Environments: A Comprehensive Characterization

This paper presents a comprehensive electromagnetic characterization of an RFID tag antenna when placed in proximity to metallic environments. The study investigates how key geometrical parameters mainly the tag-tometal gap, metal thickness and the overall size of the metallic structure are able to affect critical antenna performance metrics such as resonant frequency (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$f_{r}$</tex>), bandwidth (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$B W$</tex>), gain and radiation efficiency (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$R E$</tex>). A printed dipole RFID tag antenna, optimized for UHF operation at 915 MHz, is modeled and analyzed using ANSYS-HFSS. Through a systematic parametric study, the results reveal that the metal structure is highly affecting the RFID tag antenna characteristics and that taking into account this environment from the first design phase is crucial for optimal performance. These findings not only provide valuable insights into the reliable deployment of RFID systems in metallic environments but also pave the way for the integration of artificial intelligence (AI) models to forecast the impact of metallic surroundings and predict best spatial alignment of the antenna. This predictive capability would greatly enhance the design process and enable optimized tag placement strategies in real-life RFID applications.