In the Internet of Things (IoT) era, the demand for cost-effective, flexible, wearable antennas and circuits has been growing. Accordingly, screen-printing techniques are becoming more popular due to their lower costs and high-volume manufacturing. This paper presents and investigates a full-screen-printed 1 × 4 Quasi-Yagi-Uda antenna array on a high-transparency flexible Zeonor thin-film substrate for emerging 26 GHz band (24.25–27.55 GHz) 5G applications. As part of this study, screen-printing implementation rules are developed by properly managing ink layer thickness on a transparent flexible Zeonor thin-film dielectric to achieve a decent antenna array performance. In addition, a screen-printing repeatability study has been carried out through a performance comparison of 24 antenna array samples manufactured by our research partner from CEA-Liten Grenoble. Despite the challenging antenna array screen printing at higher frequencies, the measured results show a good antenna performance as anticipated from the traditional subtractive printed circuit board (PCB) manufacturing process using standard substrates. It shows a wide-band matched input impedance from 22–28 GHz (i.e., 23% of relative band-width) and a maximum realized gain of 12.8 dB at 27 GHz.

This article presents the design steps of a planar circularly polarized (CP) bowtie‐shaped antenna for 2.4–2.5 GHz industry, science, and medicine band. Using these design steps, an antenna model is developed. The antenna design is extensively described, simulated, measured, and analyzed. The antenna is simulated using the HFSS software and produced by laser etching of copper on a low‐cost Taconic RF‐35 substrate. The presented method of this design is easy to fabricate and is tunable to different frequencies. The produced CP planar antenna has a size of 55 × 55 × 0.25 mm³, a measured axial ratio bandwidth ranging from 2.33 to 2.49 GHz, and a measured peak gain of 3.21 dBiC. The produced antenna is fully planar, compatible with the printing process and thus suitable for Internet of Things applications.