Analysis of Radar Absorbing FSS on Foldcores and Honeycombs

Abstract

The objective of the paper is to investigate the radar absorption of honeycombs and foldcores with printed conductive patterns. These structures can be manufactured by first printing conductive Frequency Selective Surfaces (FSS) on planar substrates, which then can be used to shape foldcores and honeycombs by means of specific manufacturing technologies. Foldcores can be considered as intermediate shapes between planar sheets (where the printed patterns are perpendicular to the impinging radar waves) and honeycombs (where the printed patterns are parallel to the impinging radar wave). It is shown that the radar absorbing properties of the design strongly depend on the electrical conductivity of the paint, the size of the printed patterns and the orientation of the printed patterns with respect to the impinging wave. It is shown that a planar FSS has a maximum absorption of 50%, while foldcores and honeycombs may obtain a higher absorption due to the fact that the patterns are orientated under an angle with respect to the propagation direction of the wave.