Novel Electromagnetic Characterization Methods for New Materials and Structures in Aerospace Platforms

Abstract

The tendency over the last decades in the aerospace industry is to substitute classic metallic materials with new composite materials such as carbon fiber composites (CFC), fiber glass, etc., as well as adding electronic devices to ensure the safety and proper platform operation. Due to this, to protect the aircraft against the Electromagnetic Environmental Effects (E3), it is mandatory to develop accurate electromagnetic (EM) characterization measurement systems to analyze the behavior of new materials and electronic components. In this article, several measurement methods are described to assess the EM behavior of the samples under test: microstrip transmission line for a surface current analysis, free space to obtain intrinsic features of the materials and shielding effectiveness (SE) approaches to figure out how well they isolate from EM fields. The results presented in this work show how the different facilities from the National Institute of Aerospace Technology (INTA) are suitable for such purposes, being capable of measuring a wide variety of materials, depending on the type of test to be carried out.

Material Relative Permittivity Determination From the Inhomogeneous Transmission-Line Secondary Parameters

“…The new approach's complex effective permittivities are calculated using (36). The correction coefficient is 0.846 X  when utilizing (18). Its formulation says that it depends on the fixture and the sample material.…”

“…The literature suggests several alternative methods in the electromagnetic area [9]- [11], classified into two groups: broadband and narrowband [12], destructive and non-destructive [13]- [15], resonant and non-resonant [16], [17], direct and indirect methods, or distributed and lumped elements [11]. Inside these two groups are found six main techniques [18]- [20] according to the application domain and the state or kind of material to be characterized [21]. These six methods are Free-space [9], [22], [23], resonant cavity [24]- [26], capacitive or parallel plates capacitor [27], inductance [11], [28], probes [29], [30], and transmission line [31]- [33].…”

A Subcell Finite-Difference Time-Domain Implementation for Narrow Slots on Conductive Panels

“…In the second test case (Figure 12), the panel is made of CFC material (referred to as CFC-"blue" in ref. [27,29]), and it has two pairs of semicircular slots. The box has been tested in the reverberation chamber at INTA facilities.…”