A wide-band high gain beamsteerable variable patch reflectarray antenna for THz applications

Abstract

This article proposed a compact size, high gain, wideband reflectarray antenna for THz and 6 G applications. To enhance the aperture efficiency and gain, a single layer L-shape delay line-based unit cell with a size of 0.45λ0 is adopted. The λ0 is the free space wavelength at 1.35 THz. The SiO2 substrate is sandwiched between L- shape delay line and the ground plane of gold. The unit cell, equivalent parallel RLC circuit modelled with gap coupled capacitance is also presented which is validated through the Ansys-High Frequency Structure Simulator (HFSS) and Advanced Design System (ADS). The dimension of the RA is 3 mm having 610 elements. It is excited by the pyramidal horn antenna at an optimum distance (F/D =1.21). The optimum ratio (F/D) is calculated with the help of the cosq model at −10 dB edge taper. The operating bandwidth is obtained 46.15 % from 1 to 1.6 THz. The reflection phase and magnitude are 500° and 3.93 dB at 1.35 THz. It is adjusted by varying the length of the delay line. The maximum aperture efficiency and realized gain are 35 % and 28 dBi respectively. The Side lobe level is −15.5 dB and the Co-Cross polarization level is below −30 dB. © 2024 Elsevier GmbH