A New Genetic Algorithm Approach for Hybrid-Domain Spectral Signature Design

This paper presents a Genetic Algorithm (GA)-based methodology for designing high-capacity spectral signature tags for chipless RFID applications. By integrating Frequency Shift Keying (FSK) and Amplitude Shift Keying (ASK), the proposed method enables hybrid-domain encoding, increasing bit capacity without additional resonators. The tags, fabricated using high-resolution screen printing, were experimentally validated through S-parameter measurements, demonstrating strong correlation with simulations. The results show a maximum bit capacity of 12.59 bits, a spectral bit capacity (SBC) of 4.2 bits/GHz, and a spatial bit density (SBD) of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{1. 5 7}$</tex> bits <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$/ \text{c m}^{\text{2}}$</tex>, achieving a balance between spectral efficiency and compact design. Comparative analysis with state-of-the-art solutions highlights the method's potential for anticounterfeiting, secure identification, and high-density RFID applications.