A compact low-profile circularly polarized wearable antenna for 5G communication

Abstract A compact, low-profile, and flexible circularly polarized antenna is proposed for off-body 5G wearable applications, featuring a unique folded key-shaped parasitic strip integrated on a Cordura textile substrate. The design excites two orthogonal modes using an asymmetrical feed line, folded stub, and slotted partial ground to achieve circular polarization with a 3 dB axial ratio bandwidth of 21.42% (3.8–4.7 GHz), effectively covering 5G NR bands n77 (3.3–4.2 GHz), n78 (3.3–3.8 GHz), and partial n79 (4.4–5 GHz). The antenna exhibits a measured impedance bandwidth of 66.98% from 2.8 to 5 GHz and a peak gain of 5.2 dBic, while maintaining a compact footprint of 0.28 λ 0 × 0.14 λ 0 at 2.8 GHz. Fabricated on a flexible textile with excellent mechanical and electromagnetic properties, the prototype demonstrates strong agreement between simulation and measurement, ensuring stable performance under conformal conditions. This design enables high-speed data transfer, robust off-body connectivity, and accurate real-time monitoring, making it highly suited for next-generation wearable 5G systems with strict constraints on size, gain, and SAR compliance.