Tunable high-gain graphene patch antenna for THz massive MIMO applications using FSS

In this paper, a tunable high-gain graphene-based terahertz (THz) patch antenna is imple-mented and numerically studied. The antenna contains a graphene patch on top of a sili-con dioxide substrate with a bottom ground plane made of gold. The designed graphene antenna operates in the fundamental TM10 mode at a resonant frequency of 0.61 THz. A single-element graphene patch antenna provides the boresight radiation pattern with a gain of 1.57 dBi, and a radiation efficiency of 32%. A double split ring resonator-shaped fre-quency selective surface (FSS) is designed and numerically studied to improve the gain of the graphene patch antenna. The FSS loaded at the top of the antenna formed a Fabry-Perot cavity. The antenna with superstrate improves the gain from 1.57 to 4.87 dBi and radiation efficiency from 32 to 55%. It is observed that the FSS enhanced the gain of the antenna around 3.3 dBi and improved the radiation efficiency around 23%. The three differ-ent sizes of patch antenna sub-arrays 2x2 , 4x4 , and 8x8 are implemented and numeri-cally studied. The sub-arrays can be used for implementing THz massive multi-input-multi-output (MIMO) applications. The sub-array enhances the gain and it also provides flexibility in the design of the beamforming massive MIMO antenna. The multibeam can be achieved by applying different phases and amplitudes to different sub-arrays. Moreover, The designed antenna response can be tuned by applying an electrostatics DC bias, which alters the surface conductivity of the graphene patch and the tunability in the antenna response achieved. The tuning frequency range of the designed graphene patch antenna around 0.5-0.65 THz. The advantage of the THz antenna provides high-speed communica-tion, greater bandwidth, non-ionizing signal nature and compactness.

Automated summary

In this paper, a tunable high-gain graphene-based terahertz (THz) patch antenna is implemented and numerically studied. The antenna achieves improved gain and radiation efficiency by utilizing a double split ring resonator-shaped frequency selective surface (FSS). Additionally, different sizes of patch antenna sub-arrays are explored for implementing THz massive multi-input-multi-output (MIMO) applications. The antenna response can be tuned by applying an electrostatics DC bias.