Abstract
Objective: The next generation wireless communication systems are a major research concern of THz systems. The THz band offers very large bandwidth which is required for applications involving ultra high data rates. The objective of this research paper is therefore, greatly focused on the design and analysis of an ultra wideband antenna providing bandwidth enhancement. The use of graphene patch as conducting material in the antenna possesses enormous potential to enhance gain, radiation efficiency, radiated power and bandwidth on account of extraordinary electromagnetic properties and functionalities of the graphene material.
Method: The graphene based nano-antenna has been accurately designed using finite element method (FEM) based high frequency simulator (HFSS) software. This design introduces truncated corners/edges in square nano-patch antenna with semi-circular radius of 0.7 µm to the microstrip feeding line on SiO2 as substrate with thickness of 1.8 µm and permittivity of εr= 4 in THz region.
Result: The proposed design achieves the impedance bandwidth of 1.39 THz at 13.0 THz, 1.36 THz at 15.0 THz and more than 5THz at 18.0 THz. The 3D plot depicts gain and directivity, having maximum value of 7.1011 dB and 7.2781 dB respectively at the resonant frequency. Truncations in the antenna introduce co polarization and cross polarization. Further the radiation efficiency for graphene based arc truncated square patch antenna on silicon dioxide substrate is determined as a function of frequency for operating frequency band and has been observed to be more than 90% at respective resonant frequencies.
Conclusion: The performance of graphene based antenna has been evaluated considering equally truncated arcs on its opposite corners and their effect on antenna characteristics is analyzed by determining different parameters including bandwidth, return loss, VSWR, directivity, gain, radiation efficiency, 2D and 3D radiation patterns. The antenna provides improved impedance bandwidth of more than 5 THz in the band of operation from 10 to 20 THz. Moreover the gain, directivity and radiation efficiency achieved are much improved for the proposed graphene antenna.
Keywords: Graphene, SPP, Nano-antenna, Terahertz, HFSS, FEM, Arc truncated antenna.
Graphical Abstract