Wideband Compact Flexible Patch Antenna Design on Polydimethylsiloxane (PDMS) for Wearable Technology

This paper provides the design of a wideband compact flexible rectangular slotted patch antenna on polydimethylsiloxane (PDMS) and its performance analysis for wearable applications. Rectangular slots on the patch plane and partial ground are included to improve the operational bandwidth (BW) of the antenna. The proposed antenna is designed on a flexible PDMS substrate with relative permittivity of 2.74 and loss tangent of 0.057 and optimized to a small size of 35 × 25 × 2 mm3 using a powerful, 3D electromagnetic simulation software package (Computer Simulation Technology) studio suite to satisfy the needs of lower fifth generation, Worldwide Interoperability for Microwave Access, Wireless Fidelity, and Industrial, Scientific, and Medical band wireless applications. The proposed antenna with a microstrip line feed has two resonant frequencies at 3.5 GHz and 4.85 GHz and it operates over the frequency range of 2.53 GHz to 5.81 GHz. In free space, the antenna provides a large BW of 3.28 GHz, a maximum radiation efficiency of 85.25%, and acceptable return loss, Voltage Standing Wave Ratio, gain, directivity, and radiation characteristics over the operational frequency range. Under the on-body condition, the antenna’s performance analysis, bending analysis, and Specific Absorption Rate (SAR) analysis were also performed on a body phantom model, yielding positive results with SAR values less than the recommended safety limit of 1.6 W/kg. The comparative performance analysis proves the suitability of this antenna for applications in wearable electronics.