A Triple-Band Antenna for Indoor 5G Applications

In this paper, a Triple-band antenna for 0.7/3.5/28 GHz is proposed and studied for 5G operations. The antenna consists of a folded monopole, C-shaped monopole and four patch arrays to generate three resonant modes for triple-band operation. The folded monopole which is fed by S-shaped strip generates a frequency band at 700 MHz. By couple-feeding of C-shaped monopole through and C-shape strip, a frequency band can be generated at 3.5 GHz. These two elements have an omnidirectional pattern, and they cover the sub-6 GHz band for 5G application. The four patch arrays have a resonance frequency of 28 GHz with a directional radiation pattern. The antenna is designed on a RO-5880 substrate with a total area of 135 mm x 50 mm. Plots of the return loss and radiation pattern have been presented and discussed to show the suitability of the design for 5G applications.