Design of an ITO‐Based Multifunctional Absorber Featuring Acoustic and Thermal Insulation With Optical Transparency

ABSTRACT This paper presents a transparent dual‐polarized sound‐insulating and thermal‐insulating electromagnetic absorber based on indium tin oxide (ITO) films and polymethyl methacrylate (PMMA). Simulation results demonstrate that the absorber achieves broadband absorption over the 0.87–6.7 GHz range, with a relative bandwidth of 154%. The absorption mechanism is further clarified through analysis of surface current distributions and equivalent circuit model (ECM). Experimental measurements show good agreement with the simulation results. Compared with conventional absorbers, the proposed structure not only effectively absorbs electromagnetic waves but also integrates multiple functions, including optical transparency, sound insulation, and thermal insulation. It is highly suitable for multifunctional electromagnetic stealth applications requiring the integration of transparency, acoustic isolation, and thermal isolation, and shows broad prospects for window‐integrated applications, particularly in the area of electromagnetic stealth for windows of military assets, such as military vehicle windows and aircraft pods.