Analysis of Surface Wave Attenuation in Double-Layer Magnetic Absorbing Sheet for Wide Frequency Range Application

We firstly derived the simplified formulas for calculating attenuation constants of surface wave in double-layer magnetic absorbing sheets (MASs). The fabricated two kinds of magnetic absorbing sheets, having advantages in the low and high frequency range respectively, were used to design a group of 0.5 mm-thick double-layer sheets. Numerical calculation results show that the surface wave attenuation constants of double-layer absorbing sheet with a proper combination of the two MASs can be significantly enhanced in the whole frequency range, compared to those single-layer sheets of the same thickness. Furthermore, the simulations of monostatic RCS reduction of the metal slab coated with double-layer MAS well confirm the calculation analysis. This work demonstrates that it is feasible for double-layer magnetic absorbing sheet to enhance the surface wave attenuation ability and broaden application frequency range.