Design and analysis of an optically transparent ultra-wideband absorber covering C-, X-, ku-, k-, ka- bands

Abstract

In this paper, an optically transparent ultra-wideband electromagnetic absorber (EMA) is designed using indium tin oxide (ITO) film. To achieve a transparent property, the traditional dielectric substrate and copper are replaced by polyethylene terephthalate (PET) and ITO film. The ultra-wideband absorbing is achieved through the combination of multilayer periodic ITO structures etched on flexible PET layers. The simulation results show that the design can absorb EM waves in the frequency range of 3.72-42.42 GHz (relative bandwidth 165.75%), while its overall thickness is only 0.669λ 0 (λ 0 is the wavelength at the center frequency of EMA). The design also has the property of polarization insensitive and angular stability. Finally, the absorber is fabricated and measured to prove the effectiveness.