Control of dielectric properties of micropattern printed fabric for radar absorbing structures

Abstract

Recently, research has been carried out on radar absorbing structures (RASs) that simultaneously perform structural functions and provide low observability. The method of imparting conductivity by mixing a resin with conductive particles, such as carbon nanotubes, has been utilized since the early stages of RASs. This is advantageous because it enables high permittivity through a relatively simple process. However, the electromagnetic properties vary considerably, and the structure fabrication is complicated owing to the high viscosity. Additionally, it is challenging to analytically predict the electromagnetic properties of specimens before their permittivity can be measured. In this study, a high permittivity composite material was investigated, wherein the permittivity can be controlled and predicted analytically. Printed electronics were applied on the surface of glass fabric using a conductive paste to produce a micropattern printed fabric (MPF). The MPF was then studied to predict and control the permittivity of the composite material. In an MPF, conductive particles are distributed into micropatterns designed on the surface of glass fabric; therefore, uniform permittivity was obtained and could be controlled by moderating the parameters of micropatterns, such as pattern size and aspect ratio. The mechanical properties of the MPF were also investigated.