Rational design and fabrication of optically transparent broadband microwave absorber with multilayer structure based on indium tin oxide

A multilayer metamaterial absorber (MMA) with optically transparent and broadband microwave absorption characteristics based on Indium Tin Oxide (ITO) and polymethyl methacrylate (PMMA) was designed and fabricated. The microwave absorption properties can be regulated by the resistance of ITO and the structural parameters of the unit cell. In the frequency range of 2.64–18 GHz, more than 90 % microwave absorption can be achieved. The microwave attenuation mechanism was investigated through equivalent electromagnetic parameters, impedance matching, electric and magnetic field distribution, power loss density and layer electric current at special frequencies. The microwave absorption performance at different incident angles under TE and TM polarization models was investigated to explore the angle-sensitive properties. The average transmittance of the absorber in the visible light wavelength range (400–800 nm) was also measured. The experimental and simulated microwave absorption rates are in accordance, indicating the potential application of the proposed absorber in the field of transparent microwave absorption.