Low-Cost Electromagnetic Absorbers for Shield Packaging

In this article, a low-cost solution to tackle the problem of electromagnetic interference (EMI) is proposed for shield packaging industry. The absorber consists of a circularly shaped frequency selective surface (FSS)-based structure engraved on an acrylic sheet. Each unit cell of the absorber structure is filled with plaster of Paris (POP) as a dielectric material backed with a copper foil acting as ground plane. The top of this FSS-based structure is covered with a thin sheet of acrylic sheet. The periodicity of the unit cell is
$0.4\lambda _{0}$
, and the thickness of the absorber is only
$0.12\lambda _{0}$
, where
$\lambda _{0}$
is the wavelength of free space at the lowest absorbing frequency. A polarization-independent behavior of the absorber is depicted up to 45° angles of incidence. A detailed parametric study is carried out on high-frequency structure simulator (HFSS) simulation tool, and a prototype model is developed. Finally, the simulated result is verified with measured results, which shows a good agreement between the two. It is found that the proposed absorber structure provides a viable solution for absorbing the EMI at
$X$
-band.