volume | PIER Journals

Abstract

This paper presents the design and performance evaluation of a flexible, multilayer wearable antenna optimized for sub-6 GHz 5G applications at 3.5 GHz. The proposed antenna introduces a fabrication-ready stackable design using textile-compatible materials, including Felt, a 2 mm EVA foam layer, and Shieldit Super. A key innovation lies in the use of low-permittivity EVA foam as an intermediate spacer, which enhances gain and impedance matching without requiring additional structural elements, thus maintaining a compact and mechanically flexible profile. The antenna achieves a peak realized gain of 7.81 dBi and a wide impedance bandwidth of approximately 15.7%, within a total thickness of just 4.34 mm. The design remains robust under bending and close-body scenarios, with specific absorption rate (SAR) analysis confirming compliance with international safety standards. Experimental and simulated results validate the antenna's consistent performance, underscoring its suitability for wearable and Wireless Body Area Network (WBAN) applications in future 5G systems.

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Dr. Muhammad Fitra Zambak

Dr. Ismahayati Adam

Dr. Mohd Najib Mohd Yasin

Dr. Safpbri Johari

Prof. Ping Jack Soh