Dual-Polarized Angularly Stable High-Impedance Surface

The angular and polarization stability of the effective magnetic wall behavior is critical for successful applications of high-impedance surfaces, especially in low-profile antennas. We suggest an approach to realization of a high-impedance surface with unique magnetic-wall resonance for all incidence angles and for both TE-and TM-polarizations of incident plane waves. In order to achieve this goal we apply the concept of a grounded uniaxial material slab as a realization of a HIS surface and find the effective material parameters required for the unique parallel resonance of the surface impedance. We show that these parameters can be realized with a racemic arrangement of quasi-planar resonant chiral particles. The analytical model of the structure agrees well with full-wave numerical simulations of particular realizations. The maximal deviation of the magnetic-wall resonance frequency in the simulated example is smaller than 0.2% for both polarizations and for the incidence angles varying from 0 to 85 degrees. To our knowledge, this is a qualitatively significant improvement of previously obtained results.