A Bus Shaped Tri-band Antenna for Sub-6 GHz 5G Wireless Communication on Flexible PET Substrate

The emergence of 5th generation (5G) wireless technology has triggered the need for low-cost, compact, high-performance, and multi-band antennas, especially for flexible and wearable applications. This paper is an effort in this direction, and presents a compact and flexible antenna which operates at 5.3 GHz, 5.6 GHz, and 5.8 GHz. These bands fall in sub-6 GHz band allocated by the Federal Communications Commission (FCC) for potential 5G applications. The flexible antenna is designed on 0.1 mm thick Polyethylene Terephthalate (PET) substrate with loss tangent of 0.002 and relative dielectric constant (ε
_r
) of 3. The antenna geometry consists of symmetrical slots based bus-shaped patch which is excited by microstrip line inset feed having an impedance of 50 Ω. The overall profile of the antenna is 44 mm×70 mm×0.1 mm(LxWxH). Simulations using ANSYS High Frequency Structure Simulator (HFSS) show that the antenna has S
₁₁
values of -18.5 dB at 5.3 GHz, -26.76 dB at 5.6 GHz, and -12.79 dB at 5.8 GHz. It has a Voltage Wave Standing Ratio (VSWR) of 1.27 at 5.3 GHz, 1.096 at 5.6 GHz, and 1.59 at 5.8 GHz. The antenna demonstrates gain of 7.8 dB at 5.3 GHz, 5.9 dB at 5.6 GHz, and 4.39 dB at 5.8 GHz. The proposed antenna exhibits a very good radiation efficiency of 86.5%.