Frequency-reconfigurable miniature antenna with circular polarisation for sub-6 GHz IoT applications

Applied Science Research Laboratory, National School of Applied Sciences, Mohamed I University, Oujda, Morocco

Published online: 24 June 2026

Abstract

This study presents the design and analysis of a miniature circularly polarized spiral antenna incorporating a frequency reconfiguration mechanism based on two PIN diodes, enabling broadband coverage dedicated to IoT applications below 6 GHz. The antenna is fabricated on a Rogers RT-5880 substrate, selected for its low losses and high electromagnetic performance. Despite the integration of the reconfiguration system, the structure maintains compact dimensions of 16.5 × 12 × 0.79 mm³, ensuring easy integration into embedded devices with tight space constraints. The frequency reconfigurability provides dynamic adaptation of the operating band, allowing it to meet the various IoT standards operating in the sub-6 GHz range. The design and performance evaluation were performed using the CST Studio Suite electromagnetic simulation software. The results obtained confirm the proposed antenna's ability to provide effective broadband coverage while maintaining a compact design, making it a relevant solution for IoT, mobile, and low-power wireless communication systems.