Compact tunable terahertz self-diplexing antenna with high isolation

A tunable terahertz (THz) slotted monopole antenna is implemented with self-diplexing capability. The radiating arms of antenna are filled with the graphene strips. The variation in electrical parameters of graphene alters the surface current distribution in the radiating arms which results in tuning the antenna response through individual input ports. Antenna operates in frequency range 4.75–5.34 $THz$ and 5.57–6.76 $THz$ with the application of input at port-1 and 2, respectively which can further be tuned with the reported biasing schemes. The antenna structure utilizes the orthogonal radiating slots which provides high isolation more than 150 dB between the ports in compact antenna geometry. An electrical equivalent circuit is prepared to verify the antenna operation. In addition, antenna offers the peak gain 3.83 dBi at port-1 and 6.06 dBi at port-2 in the operating passband along with the efficiency of more than 80%. Antenna provides the compact geometry with tunable self-diplexing capability and can be suitable for future wireless applications requiring the simultaneous transmit and receive systems.