CSRR and EBG loaded wideband THz dielectric resonator MIMO antenna for nano communication and bio-sensing applications

In this paper, a wideband Graphene-inspired dielectric resonator THz MIMO antenna is designed. The antenna has dimensions of 56 × 56 × 3.6 μm³ and is designed on a Rogers RO3035 substrate with a relative permittivity of 3.6 and loss tangent of 0.0015. This antenna works in the range of 6.0 THz-12.5 THz (70.76 %) with a peak gain of 7.68 dBi and radiation efficiency (>70 %) is suitable for use in medical imaging and THz wireless near-field applications. A CSRR is loaded to obtain band notch characteristic for avoiding interference between nearby wireless devices in the range of 10.6–10.8 THz. EBG was also introduced with a patch antenna to reduce surface wave loss and improve isolation, resulting in a high front-to-back ratio (FBR) in the range of 10–12.5 THz. Without the graphene disk, the silicon-based DRA did not achieve significant gain. At a chemical potential of 0.5 eV and a relaxation time of 0.1 ps, the proposed DRA demonstrated good antenna properties. By varying the chemical potential and relaxation time, frequency agility was easily achieved. A Graphene disk having a height of 3 μm is placed on a Silicon (ε_r = 11.1) based cylindrical DRA to provide high gain and improve the impedance bandwidth, achieving wide bandwidth from 6.0 THz to 12.5 THz. The proposed two element antenna performance is evaluated by parameters such as gain, return loss, isolation between two antenna elements, and diversity parameters like Envelope correlation coefficient ECC<0.1, Directive Gain >9.5 dB, Total Active reflection Coefficient >10 dB and Avg. Channel capacity loss <0.35bps/Hz so that the proposed antenna is suitable for wideband nano/optical communication in IoT-6G. Furthermore, the antenna is suitable for biological sensing applications due to its average sensitivity and FOM for hemoglobin and urine of 805.33GHz/RIU and 805.55GHz/RIU, respectively, and 3.37 and 10.55.