On the design of wide-band and thin absorbers using the multiple resonances concept

This paper describes how one can design a wide-band and thin absorber using the multiple resonances concept. Employing a simplified and yet intuitive equivalent circuit model, we can demonstrate that a thin absorber with a wide bandwidth can be designed by introducing multiple resonant circuits in the substrate backed by a planar conductor whose radar cross-ection (RCS) is to be reduced. A few design examples, including double square-loop printed on a substrate, circuit analog (CA) absorber using multiple resistor-loaded dipoles, and shunt-series connection of transmission line structures are presented to demonstrate the wide-band performance of a thin absorber utilizing a structure with multiple resonances. Both simulated and measured results are provided and compared.