Ultra-Compact, High-Efficiency 5.8 GHz Metamaterial Antenna for Wireless Applications

Abstract

This paper presents an ultra-compact, high-efficiency metamaterial antenna designed for 5.8 GHz wireless applications. The proposed antenna employs a metamaterial-based structure to achieve substantial miniaturization compared to existing designs in the literature. A split-ring resonator (SRR), directly excited by a transmission line, serves as the primary radiating element, utilizing metamaterial properties to support sub-wavelength resonance. The antenna achieves extreme size reduction, with overall dimensions of 7×9×1.6mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> (approximately λ<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</inf>/6 at 5.8 GHz), representing a 93.5% size reduction relative to a reference patch antenna, while maintaining a radiation efficiency of 95%. This study highlights the trade-off between miniaturization and gain, demonstrating that efficient radiation can be preserved even within an ultra-compact volume. Owing to its planar topology, reduced dimensions, and ease of fabrication, the antenna is well suited for compact wireless platforms such as RFID tags, embedded IoT nodes, and portable sensing devices, making it a strong candidate for next-generation wireless identification and sensing systems.