Metasurface-Assisted Dual-Port Graphene Built Nano Wearable THz Antenna with Circular Polarization and Reduced SAR

This work constructed a two-port, compact wearable antenna using a flexible polyimide substrate. Circular polarization feature inside the working regime (3.1–3.45 THz) is achieved by perturbation of graphene built circular patch. Strong terminal isolation is achieved by placing the terminal in reverse way, which keeps values over 25 dB throughout the working frequencies. Underneath the radiator, a metasurface (MS) reflector reduces the Specific Absorption Rate (SAR) by over 85% for 1-g and 10-g tissue models respectively, while increasing the radiator gain to above 6.7 dBi. Furthermore, the chemical potential of the graphene layer may be changed to tailor the radiator's working frequency, allowing for programmable behaviour. Effective operation of the antenna over 3.03-3.91 THz is confirmed by full-wave simulations in HFSS and CST. The antenna's capacity to function steadily in bending circumstances further emphasizes its applicability for adaptable THz wireless communication systems.