Analysis and Design of a Metamaterial Lens Antenna Using the Theory of Characteristic Modes

Daniel Santillán-Haro,Eva Antonino-Daviu,Miguel Ferrando-Bataller,Daniel Sánchez-Escuderos

doi:10.1155/2018/6329531

Abstract

A new single-layer metamaterial lens antenna aimed to operate at 10 GHz is proposed in this paper. The lens antenna consists of twelve capacitively coupled unit cells distributed along a ring and illuminated by an open-ended circular waveguide with a metallic resonant ring. The theory of characteristic modes is used to analyze the metamaterial lens, in order to provide an insight into the radiation characteristics of the antenna. The proposed antenna has been optimized, obtaining a large bandwidth and a maximum directivity of 12.88 dBi at 10 GHz.

Highlights

Metal lenses have attracted an increasing interest during the last decade due to their multiple applications [1,2,3,4,5,6,7,8,9]
The compactness of metamaterial lens antennas makes them very attractive for the low-cost development of metal lenses at terahertz frequencies [7], thin planar lenses for massive MIMO applications in the millimeter-wave band [8], or ultrathin planar lens antennas based on gradient metasurfaces [9]
The paper is organized as follows: Section 2 presents the geometry of the proposed antenna and the design procedure, Section 3 describes the characteristic modes of the metallic structure and the radiating behavior associated with the antenna, Section 4 shows the main results obtained with the design proposed at 10 GHz, and, Section 5 highlights the main conclusions

Summary

Introduction

Metal lenses have attracted an increasing interest during the last decade due to their multiple applications [1,2,3,4,5,6,7,8,9] In this context, different lenses have been recently proposed aimed at maximizing the gain and the efficiency of the radiating structures. Different lenses have been recently proposed aimed at maximizing the gain and the efficiency of the radiating structures These lenses are formed by periodic structures, for example, EBG (electromagnetic band gap) or FSS (frequency selective surfaces), which provide the aforementioned characteristics in a low-profile shape. The truncation of the lenses in a finite number of elements leads to inaccurate results An alternative to this analysis consists of using the theory of characteristic modes (TCM). The paper is organized as follows: Section 2 presents the geometry of the proposed antenna and the design procedure, Section 3 describes the characteristic modes of the metallic structure and the radiating behavior associated with the antenna, Section 4 shows the main results obtained with the design proposed at 10 GHz, and, Section 5 highlights the main conclusions

Antenna Structure

Analysis of Characteristic Modes

Results

Conclusion