Optimal Design of Microwave Absorbers Based on High-Impedance Surfaces

The simulation model and the optimal design methodology for absorbers consisting of metallic patches on a dielectric substrate backed by a perfectly conductive layer, have been developed. New expressions for the real and imaginary parts of the substrate permittivity are proposed to achieve a desired reflection coefficient at a specified resonance frequency. This analytical formulation is then utilized to predict the absorbance performance of various structures under both normal and oblique incidence plane waves up to 10 GHz. Validation of the obtained results is conducted by comparing them with those obtained from CST full-wave numerical simulations.