Design, simulation, and experimental investigation of a 3D-printed metamaterial inspired broadband microwave absorber

This work presents the design, full – wave simulation, fabrication, and experimental investigation of a high-performance X-band microwave absorber based on a three-dimensional (3–D) printed metamaterial-inspired pyramidal architecture. The absorber is fabricated using a resin-based lossy dielectric composite and integrated with a copper ground plane to suppress electromagnetic transmission. The proposed pyramidal structure is generated from an STL (Stereolithography /Standard Tessellation Language) geometry and analyzed using ANSYS HFSS 2024R1 under normal and oblique wave incidences to evaluate its absorption characteristics and angular stability. The proposed absorber exhibits a high-absorption response within the X-band frequency range, resulting from the combined effects of dielectric loss, gradual impedance matching, and multi-resonant electromagnetic coupling enabled by the engineered three-dimensional geometry. The absorber achieves a maximum simulated absorptivity of 99.99% at 8.39 GHz, with an effective absorption bandwidth of 2.60 GHz extending from 8.02 to 10.62 GHz for absorptivity ≥90%. The fabricated prototype is experimentally characterized to validate the simulated absorption response. The proposed resin-based 3–D printed architecture provides a lightweight and scalable approach for fabricating microwave absorbers while avoiding the geometric limitations associated with conventional subtractive fabrication. The demonstrated X–band absorption performance makes the proposed structure promising for applications in electromagnetic interference shielding, radar cross-section reduction, stealth platforms, and electromagnetic compatibility systems.