Experimental characterisation and prediction of shielding effectiveness for multilayer carbon fibre reinforced composite materials with varying configurations

This paper reports the outcomes of an experimental investigation of the shielding effectiveness (SE) for carbon fibre reinforced polymer (CFRP) composites with varying configurations. It focuses on (1) important parameters affecting the SE of CFRP laminates and (2) applicability of the transmission line (TL) theory to predict their shielding properties. Comparison of the SE profiles showed that quasi-isotropic and cross-ply configurations perform equally well in attenuating the unpolarised radiation and only a modest increase of 10 dB is achieved by doubling the number of plies due to increased absorption. The applicability of the TL model for CFRP composites was found to be limited to thin laminates with quasi-isotropic lay-up, for which the accuracy prediction was within 5 dB in the 150 MHz-1 GHz frequency range. The experimental SE values were also compared to the full wave simulation in a commercial electromagnetic simulation software, demonstrating more accurate predictions than any analytical model.