Shielding of Electromagnetic Radiation by an Artificial Magnetic Conductor Based on an Isotropic Composite Material Consisting of Capacitive Gratings

The characteristics of an artificial magnetic conductor (AMC) based on an anisotropic composite material consisting of capacitive gratings with metal elements in the form of squares or strips, each of which is shifted by one half of a period relative to two neighboring ones, are studied. Analytical expressions for estimation of the permittivity of the composite material are derived, and the condition for their applicability is formulated and tested with the aid of numerical calculation. It is shown that such an AMC can be used as a small-sized shield with a shielding band of up to 30% when a dipole emitter is located almost on its surface.