Fully Metallic Reflectarray for the Ku-Band Based on a 3D Architecture

Abstract

This document presents the design and manufacture of a reflectarray (RA) antenna for the Ku-band that is based on a fully-metallic 3D architecture. The reflectarray unit cell is formed by a square-shaped waveguide section ending in a short circuit, which is the reflectarray back ground plane. Each cell has the ability of configuring the phase of its own reflected field by means of resonators perforated on the walls of the cell waveguide section. The resonator-based waveguide cell introduces the 3D character to the design. The geometry of the resonators and the size variation introduces the phase behavior of each cell, thus, conforming the radiation pattern of the reflectarray. This design explores the potential of phase value truncation (six states and two states) and demonstrates that proper pattern results can be obtained with this phase truncation.

3-D Metamaterials: Trends on Applied Designs, Computational Methods and Fabrication Techniques

“…Fully-metallic reflectarrays are still challenging, but some prototypes are being launched. This is the case in [151] (previously cited), and the case in [153]. This last is actually interesting because the reflectarray is mechanically reconfigured and optimized to operate in the Ka-band.…”

“…This one is reported in [143]. (b): Full-metal reflectarray prototype reported in [151]. (c): Fullydielectric reflectarray prototype reported in [152].…”

“…These properties were successfully synthesized to attain single and dual-pol circular polarizers in [86] and [8], respectively. The same principles were later applied for the design, optimization and fabrication of the reflectarray [151] shown in Figure 3(b). Furthermore this same structure is currently being subject of study for a most challenging terminal which would include reconfiguration with graphene, leading to a metastructure exhibiting several functionalities [7].…”

“…However, the difference between both of them is that the SLA makes the cure in a tank full of resin while MJ cures the material after the material has been sprayed. Unit cell designs that have employed SLA in their prototyping are presented in [115,148,151,162,166]. The last technology applied for the manufacture of 3-D metamaterials using 3-D printing on plastic is called selective laser sintering (SLS) used in [163,164].…”

“…Since the 3-D printing technologies described above print the unit cells on plastic and they have conceived to be metallic, a metallization is needed to coat the surface of the printed unit cells with a highly conductive metal. Different techniques to metallize the surface of the unit cells have been seen in previous works: brush paint [123,163], spray [151], electroplating [165], electroless plating [161], sputtering [121,162], dip coating [164], and vacuum chamber metallization [166]. Metallization is a crucial part of this manufacturing process as each of the above techniques offers a level of roughness, conductivity and layer thickness that must be taken into account depending on the operating frequency range and geometry of the unit cell.…”