Tri-band antenna with metasurface-based ground plane for Sub-6 GHz 5G and 6G WPT applications

Abstract

In this paper, a spiral-shaped metamaterial-loaded rhombic slotted microstrip patch antenna is investigated for Sub-6 GHz 5G and 6 GHz tri-band applications. A 1.524 mm thick Rogers RO4003 substrate (ϵr = 3.55, LosTanδ = 0.0027) opts for the antenna design. A partially grounded mechanism is implemented to control the operating frequencies of the antenna. A 5×5 triangular unit cell metasurface is deposited beside the partial ground plane to enhance the impedance bandwidth as well as to improve the impedance matching. A G-shaped metallic structure enclosed within the rhombic slotted antenna helps in creating circular polarization (CP) properties. The presented antenna resonates at 3.28 GHz (Mid-range Sub 6 GHz 5G band), 4.94 GHz (Upper range Sub 6 GHz 5G band), and 6.92 GHz (Sub 6 GHz 6G Band) frequencies. The maximum gain offered by the antenna is 8.81 dBi. Also, the developed antenna offers CP characteristics in all three operating bands with wide axial ratio (AR) bandwidth characteristics above 400 MHz in both the first and third operating bands. The radial characteristics of the proposed antenna show its capability of receiving EM signals from all directions as desired for a WPT system. For validation purposes, a prototype is fabricated and characterized as well.