Design and Analysis of Log Periodic Slotted Tri-Band Antenna for Wearable Applications

Wearable antennas are pivotal in advancing healthcare monitoring, military communication, and IoT, offering seamless integration with fabrics and devices for realtime data transfer. High-frequency wearable antennas ensure compactness, enhanced performance, and reliable operation, making them indispensable in modern applications. This paper presents a circular patch antenna with dimensions 54.4 × 54.4 mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>, designed using a Teflon (PTFE) substrate of 1.6 mm thickness, known for its low loss, high thermal stability, and excellent dielectric properties. The design features log-periodic slots that enable multiband resonance at 11.99 GHz, 12.95 GHz, and 15.36 GHz, achieving return losses of -43.23 dB, -31.19 dB, and -22.80 dB, respectively, along with favorable VSWR, gain, and directivity. The antenna also demonstrates low Specific Absorption Rate (SAR) values, ensuring safety and reliable performance, measuring 1.23 W/kg, 1.20 W/kg, and 1.03 W/kg at 11.99 GHz, 12.95 GHz, and 15.36 GHz, respectively, for wearable applications in current practical use cases across various sectors.