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

Jaime Velasco,Ignacio Parellada-Serrano,Carlos Molero

doi:10.3390/electronics10212648

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.

Highlights

The increasing requirements in antennas for broadcast and telecommunications are becoming challenging due to the emergence of novel technologies and the fast development of new fabrication techniques—in particular, the arrival of the 5G communications standard and the establishment of operating bands at millimeter frequencies [1]
Though our final goal is the conception of a RA operating at millimeter frequencies, in this document, we focus on a Ku-band prototype with the aim of obtaining a first proof of concept
These perforations play the role of slot resonators, which drastically modify the electromagnetic response of the cell at frequencies close to their own resonance frequency

Summary

Introduction

The increasing requirements in antennas for broadcast and telecommunications are becoming challenging due to the emergence of novel technologies and the fast development of new fabrication techniques—in particular, the arrival of the 5G communications standard and the establishment of operating bands at millimeter frequencies [1]. Phased arrays exploit the ability to steer a radiation beam into a desired direction They may include the feeding network in the device architecture, which is generally supported on complex circuitry. Paradigmatic examples were reported in [28,29], where fully-metallic cells with 3D architectures were employed to design dual-band/dual-pol devices, combining both 3D architecture and full-metal cavities. These type of cells are promising since they are mechanically self-consistent, and no help of support is needed. The waveguide walls are perforated with resonators, whose role is to modify/control the individual phase of the reflected wave associated with each of the waveguide cells Under these circumstances, two kinds of RAs are presented.

Brief Description of the Unit-Cell Type

Reflectarray Design

Manufacturing and Experimental Validation

Conclusions