Broadband folded reflectarray based on single‐layer subwavelength elements using discrete phase control

Abstract

In this article, a new subwavelength element is introduced into the broadband folded reflectarray antenna (FRA). The element comprises a rectangular splitring resonator with two slits and a square patch located in the center of the rectangular ring. It can achieve superior cross polarization conversion (CPC) performance from 16.2 to 26.4 GHz with 1 dB bandwidth of 45.4%, and high orthogonal polarization isolation. Furthermore, changing the positions of two splits of the element can achieve two discrete reflection phases (0 and 180 ) with the high CPC efficiency and angular stability. To verify the feasibility, an FRA using the digitally quantized phase distribution method is designed and measured at 22 GHz. The measured results show that the 1 dB gain bandwidth of the proposed FRA is 30.8%, and the maximum aperture efficiency is 15.4%. This superior performance is comparable with the existing FRAs.

Low-Profile High-Gain Wideband Multi-Resonance Microstrip-Fed Slot Antenna With Anisotropic Metasurface

“…Metasurfaces (MSs), as quasi two-dimensional (2D) planar forms of metamaterials (MMs), have been extensively used in antenna design due to their unique electromagnetic (EM) response properties of efficient selective absorption [13], gain amplification [14][15][16][17][18], bandwidth optimization [19][20][21], filtering response [22,23], polarization conversion [24][25][26][27][28][29], etc. It is found that using a microstrip aperture coupled feed structure as an excitation element for the MSs can achieve the efficient optimization of other parameters while preserving the low-profile characteristics of the antenna structure.…”

Design of a frequency selective surface‐backed microstrip reflectarray antenna using Minkowski ring elements

“…Another effective approach for improving the bandwidth performance is to employ subwavelength elements. For single‐layer design, the gain bandwidth is significantly enhanced by using subwavelength elements 11,12 . However, the fabrication tolerance of patch sizes at high frequencies reduces the phase range of the subwavelength elements, which has become the key problem in the design of subwavelength elements 13 .…”

“…For single-layer design, the gain bandwidth is significantly enhanced by using subwavelength elements. 11,12 However, the fabrication tolerance of patch sizes at high frequencies reduces the phase range of the subwavelength elements, which has become the key problem in the design of subwavelength elements. 13 By introducing fractal structure into subwavelength unit-cells, one could take advantage of the fractal geometry and the subwavelength-sized element.…”