Broadband and wide-angle coding metamaterial absorbers for maritime environmental applications

Multilayer composites with resistive frequency-selective surfaces (FSS) show significant potential in maritime environments, where absorbers must combine broadband and wide-angle microwave absorption, low density, high strength and salt spray durability. Leveraging coding metamaterials (CMs) and an improved genetic algorithm (GA), we designed a high-performance microwave absorber. Conductive carbon ink, polyvinyl chloride (PVC) foam, carbon fiber reinforced plastic (CFRP) sheets, and quartz fiber reinforced plastic (QFRP) sheets are selected to satisfy electromagnetic and mechanical specs. Layered pattern control secures broadband electromagnetic absorption, while the improved GA optimizes wide-angle performance. Reflectivity and mechanical tests confirm −10 dB absorption over 2–18 GHz and 0–45°, with low density and high strength. Owing to rational material selection, the maritime corrosive environment has a relatively minor effect on the absorber. Results of this study provide a robust solution for the broadband and wide-angle design and application promotion of microwave absorbing materials.