28 GHz Lock and Key Shaped Flexible Textile Antenna Design for Wearable Wireless Communications

This paper proposes a 28 GHz flexible textile antenna design for wearable wireless applications, employing silk as the substrate material and a dielectric permittivity of 1.75. The size of the antenna, including the substrate, is $7 \mathrm{~mm} x 13 \mathrm{~mm} \times 1.16 \mathrm{~mm}$. The antenna design strives for great performance in terms of radiation efficiency, bandwidth, and size reduction. The antenna is precisely developed and optimized to accomplish these objectives with powerful electromagnetic simulation tools known as CST (Computer Simulation Technology). The antenna has a reflection coefficient of -32.19 dB and resonates perfectly at 28 GHz. The maximum gain of the antenna is 5.85 dBi. The antenna’s radiation effectiveness in open space is 56%. The performance of the antenna was further investigated by replacing the silk substrate with 10 other textile substrates. The suggested textile antenna has outstanding performance characteristics such as a wide working bandwidth, high radiation efficiency, and a small dimension. Because of the conformal nature of the textile substrate, the antenna fits on any surface, improving user friendliness and lowering interference. The design also considers the antenna’s performance, which ensures dependability and robustness in real-world circumstances.