Graphene-Based Quad-Port MIMO Reconfigurable Antennas for THz Applications

In this research, two graphene-based THz patch antenna structures for THz applications are reported. In the unit cell analysis, it can be pointed out that the patch is made of graphene, and the substrate is made of silicon dioxide. While its dielectric permittivity is 3.7. The operating frequency of the MIMO antenna is designed at 0.6 THz. In the plan of the MIMO reconfigurable antenna, cells are arranged vertically. Reconfigurable conditions can be achieved by changing the chemical potential or in other words the bias voltage of graphene patches. The amount of chemical potential in the original project of both quad-port MIMO reconfigurable antennas is considered to be 0.6 eV. In the results of the first antenna, S11 is less than -10 dB in the range of 0.58786 THz through 0.63112 THz. In the results of the second antenna, S11 is less than -10 dB in the range of 0.57814 THz through 0.63391 THz. In the results of the first antenna, maximum efficiency is reported about 65%. In the results of the second antenna, maximum efficiency is reported at about 72%. Finally, peak realized gains, radiation efficiencies, far-field 2D radiation patterns, VSWRs, current distributions, envelope correlation coefficients (port1-port2, port1-port3, port1-port4), and diversity gains (port1-port2, port1-port3, port1-port4) have all been reported over the operating frequency band for two antennas.