Significant Factors in the Inkjet Manufacture of Frequency-Selective Surfaces

Badredin M Turki,Rachel Saunders,Sebastian Wunscher,Mohamad Ali Ziai,Edward Ted A Parker,Stephen G Yeates,Ulrich S Schubert,John C Batchelor,Veronica Sanchez-Romaguera

doi:10.1109/tcpmt.2016.2561972

Abstract

Additive fabrication of electromagnetic structures by inkjet printing technology is both cost effective and compatible with a wide range of environmentally friendly substrates, enabling the fabrication of frequency-selective surface (FSS) arrays with line dimensions less than 0.1 mm, which is difficult to achieve with conventional subtractive techniques. Several approaches, such as savings in ink by depositing it at the edges of dipole elements where the surface current tends to maximize, have been investigated in order to produce low-cost frequency-selective panels with acceptable level of isolation. The FSS transmission characteristics were improved by jetting multiple ink layers on the whole elements and at the edges. The electrical resistance of various arrays have been measured and analyzed and has been used to assess the performances of the FSS.

Highlights

THE wide spread of wireless technologies in recent years, together with the era of Internet of Things in the built environment, has increased concerns for information security, as well as quality of communication arising from adjacent sources of interference, as many of the wireless technology bands have become congested
This effect is more noticeable for the frame dipole elements, as they are more sensitive to the droplet spreading effect, as the droplets would spread on both sides of the frame’s arms, whereas in case of solid dipole elements it will be proportionally less significant as they will be overlapping with the adjacent ink droplets
This paper investigates factors that contribute to the inkjet manufacture of frequency selective surfaces with acceptable levels of performance

Summary

INTRODUCTION

THE wide spread of wireless technologies in recent years, together with the era of Internet of Things in the built environment, has increased concerns for information security, as well as quality of communication arising from adjacent sources of interference, as many of the wireless technology bands have become congested. Minimization of the amount of ink used is desirable in reducing both cost and environmental impact; there remains a major challenge in overcoming the greater risk of defects in the printed elements which in turn would affect the performance of the FSS. Such defects are typically elements with high electrical resistance, or with total discontinuities in the conducting path; some of those defects are described in [14]. An element resistance study of all FSS designs is reported here in order to quantify the relation between the level of isolation and the dc resistance

Design and Fabrication

Measurement

PRINTING DEFECTS

RESISTANCE STUDY

Findings

CONCLUSION