Complex shaped periodic corrugations for broadband Bull\u2019s Eye antennas

Despoina Kampouridou,Alexandros Feresidis

doi:10.1038/s41598-021-94232-2

Abstract

Periodically corrugated metallic antennas have been developed in recent years from microwave to THz frequencies, due to their advantages of highly directive radiation patterns, low profile and ease of fabrication. However, the limited gain bandwidth of such antennas remains one of their inherent disadvantages. In terms of design, the majority of the existing implementations in literature utilize the standard rectangular shaped corrugated unit cell. In this paper, we propose novel complex shaped corrugated unit cells that produce a broadband performance when assembled in a periodic configuration. Two broadband prototypes are presented at the Ku frequency band that are formed of hybrid shaped corrugations. The first prototype of six periodic rings achieves, for the first time, a flat gain simulated response with a maximum value of 15.7 dBi, 1-dB gain bandwidth of 16.4%, and an extended 3-dB gain bandwidth of 19.64%. The second novel prototype of five rings achieves an enhanced 3-dB gain bandwidth of 15.2% and maximum gain of 18.1 dBi.

Highlights

In recent years, there has been a significant research interest in a family of planar corrugated metal antennas (Bull’s Eye antennas) that radiate a via subwavelength aperture etched off the centre of the metallic structure, with high gain radiation patterns[1,2,3]
The typically limited gain bandwidth of corrugated metallic antennas is expanded by introducing novel concepts of corrugated unit cells
The first proposed model of six rings achieves a maximum gain of 15.7 dBi and a 1-dB gain bandwidth of 16.4%

Summary

Introduction

There has been a significant research interest in a family of planar corrugated metal antennas (Bull’s Eye antennas) that radiate a via subwavelength aperture etched off the centre of the metallic structure, with high gain radiation patterns[1,2,3]. These antennas are directly scalable from microwave to low THz frequencies and offer the advantages of high directivity, very low profile (less than a wavelength) and easy design and fabrication process[4]. The second prototype of five rings achieves a maximum gain of 18.1 dBi, along with an extended 3-dB gain bandwidth of 15.2% Both antennas outperform standard Bull’s Eye antennas of similar size and gain

Methods

Results

Conclusion