Radiation characteristics of a dipole embedded below a HIS

Numerical investigation on the radiation characteristics of a dipole embedded between a high impedance surface and a ground plane are proposed. The geometry is realized by periodic repetition of a unit cell in two orthogonal directions and insertion of the dipole is possible because of the simplicity of the structure that does not use vias or shorting pins. Starting from the dispersion diagram of the unit cell, slow and fast waves regions are determined, and the radiative behaviour for the two different cases is investigated.