Performance Enhancement of Terahertz Antenna Embedded with 8x8 array of Frequency Selective Surface

Terahertz technology is becoming popular due to the realization of Terahertz sources and detectors. The THz frequency spectrum is explored in biomedical imaging to analyze the chemical compositions of brain. Antenna is the vital component which acts as radiating component in THz imaging system. The objective of the presented paper is to increase the performance of THz rectangular patch antenna intended to be used in THz imaging system. We report the theoretical investigation of FSS operating in THz regime. The preliminary research aims to focus on enhancing the THz planar antenna of the imaging system by using a metamaterial substrate. An array of 8x8 FSS microstructures is printed on the silicon substrate of permittivity 11.9. Frequency selective surface (a class of metamaterial) increases the gain of THz patch antenna due to reflection in the operating frequency of 1.0150 THz. The paper reports an improvement in return loss from -16.424 dB to -31.4049 dB when the rectangular patch antenna is placed on the substrate consisting of 8x8 array of square loop FSS. The THz antenna system is designed using HFSS 18 and the frequency response of unit cell of FSS is examined using floquet mode in CST.