Experimental analysis based on optical model and electromagnetic properties of multilayer absorbers

Author: 
Samuel M. Leal da Silva, Newton Adriano S. Gomes, Simone de S. Pinto, Alberto José O. Faro andMirabel C. Rezende

This research aims to contribute with the design optimization of multilayer absorber material applicable in stealth technologies. This study involves a pre-analysis of the electromagnetic properties of five individual plates (absorbing layers), considering the reflection and transmission coefficients. From these characteristics was established the best combinations of the individual layers in sets of three layers. For this, five plates based on styrene-butadiene rubber (SBR) matrix loaded with carbon black (2-50 phr) were processed. Electrical conductivity, electric permittivity, and the reflection and transmission coefficients at NRL Arch of the five plates were measured. The results were correlated to obtain the best impedance matching of the sets of three layers looking for the lowest reflectivity. The proposed experimental data correlation was compared to computational simulations based on the model of Small reflections in stratified medium. Besides this, all possible arrangements of three layers were experimentally evaluated by NRL Arch in the range of 8 – 11 GHz. The top five arrays with three layers are shown. The experimental results present a good fit with the performed simulations. The good adjustment between the experimental measurements and theoretical predictions allow us to state a pre-analysis route to support the processing the multilayer microwave absorbers.

Paper No: 
1457