Mutual Coupling Reduction in Phased Array Antennas Applying High-Impedance Surface at X Band

José Bruno O De Araújo,Vanessa P R Magri Souza,Jorge M Souza,Tadeu N Ferreira,Leni J De Matos,Maurício W B Da Silva,Glaucio L Siqueira

doi:10.1590/2179-10742020v19i11773

Abstract

This paper presents a microstrip phased array using High Impedance Surface - Electromagnetic Band Gap (HIS-EBG) in order to minimize the effects of mutual coupling among the antenna elements. Each element of the array is fed by a coaxial cable allowing the beam steering by controlling the signal of the input port of each element. This phased array operates at X Band as well as the band-gap of the HIS-EBG structure. Its main applications are satellite communication and broadcasting systems. Results show reductions in the mutual coupling up to 12 dB, and improvements in the return loss and gain.

Highlights

The use of phased array antennas has been increasing in the last few years due to the fact that they present several advantages over the use of single antennas, such as the flexibility to steer the transmitted signal
It is possible to observe that the proposed High Impedance Surface - Electromagnetic Bandgap (HIS-EBG) structure provides an electromagnetic bandgap over the X-band, i.e. there is no solution over this frequency range, which means that surface waves at frequencies within this gap are forbidden to propagate through the HIS-EBG [12]. This happens due to the interaction of the metal vias with the surface wave, which slows down the received May 2019; for review May 2019; accepted 9 Dec 2019. This bandgap implies that surface waves at frequencies encompassed by the gap will not propagate through the HIS-EBG structure, and, it can be applied to arrays to reduce the mutual coupling among the antenna elements
In order to minimize the effects of mutual coupling in a microstrip phased array, a mushroom-like HIS-EBG structure was design and simulated on HFSS to create an electromagnetic bandgap at the XBand, which has sub-wavelength dimensions

Summary

Mutual Coupling Reduction in Phased Array

José Bruno O. de Araújo1* , Vanessa P. Abstract— This paper presents a microstrip phased array using High Impedance Surface - Electromagnetic Bandgap (HIS-EBG) in order to minimize the effects of mutual coupling among the antenna elements. Each element of the array is fed by a coaxial cable allowing the beam steering by controlling the signal of the input port of each element. This phased array operates at X Band as well as the bandgap of the HIS-EBG structure. Results show reductions in the mutual coupling up to 12 dB, and improvements in the return loss and gain

INTRODUCTION

Main Lobe Direction θ

CONCLUSION