Dual Metasurface Loaded Tunable Silicon‐Graphene Built Dielectric MIMO Filtering Antenna With High Far‐Field/S‐Parameter Isolation in THz Domain

The design and analysis of 2‐terminal Si‐Graphene radiator functioning in the THz band is explained in this research. The suggested structure has a number of unique characteristics. First, by using an antenna–filter integration technique, the antenna's gain response naturally exhibits bandpass characteristics. Second, SNG metasurface suspended above 2‐terminal radiator improves the S‐parameter based isolation to above 30 dB. Third, a partial reflecting surface (PRS) positioned above SNG MS to improve far‐field isolation by tilting pattern to ±45°. Layering of graphene over Si‐ceramic creates frequency tunability to the working spectrum. Simulation results obtained using both CST and HFSS demonstrate that the proposed antenna operates over a wide impedance bandwidth of 0.58 THz (4.2–4.78 THz), while achieving a 3‐dB axial‐ratio bandwidth of 0.39 THz (4.21–4.60 THz). The antenna exhibits a peak gain of approximately 5 dBi within the operating band and maintains port isolation better than 30 dB throughout the frequency range. These characteristics make the proposed antenna a promising candidate for future THz and 6G wireless communication systems.