Design and analysis of dual-band circularly polarized coplanar waveguide antenna for millimeter-wave 5 G applications

Abstract A dual-band circularly polarized antenna has been designed for millimeter-wave applications, operating over the frequency ranges of 27 GHz to 28.45 GHz and 34.3 GHz to 35.8 GHz. The proposed coplanar waveguide (CPW) antenna features a central feed line serving as the main signal conductor, with circular structures arrayed around it acting as radiating elements. These elements are strategically designed for optimal performance at millimeter-wave frequencies. The antenna, with physical dimensions of 8 mm × 7 mm × 0.757 mm, corresponds to approximately 0.72 λ × 0.63 λ × 0.068 λ at 27 GHz, where λ represents the free-space wavelength. Fabricated on a Rogers RT/duroid 5880 substrate, the antenna’s practical measurements exhibit good agreement with simulated results. The antenna achieves an overall gain of up to 6 dBi across the operating bandwidth, maintaining an axial ratio of less than 3 dB. These results confirm the antenna’s efficacy, making it a superior choice for millimeter-wave 5 G applications.