Dual polarization planar radiating element and array antenna comprising such a radiating element

A dual-polarization planar radiating element having an external metal grid, at least one metal patch concentric with the external metal grid and a cavity separating the metal grid and the metal patch, the grid and the patch having a polygonal shape delimited by at least four pairwise opposite sides, and two orthogonal directions of polarization associated with two orthogonal electric fields Ev and Eh, at least one of the directions of polarization being parallel to two sides of the polygon. Each side of the metal patch parallel to a direction of polarization is linked electrically to a zone of the external grid where one of the electric fields Ev or Eh is a minimum. The invention exhibits the advantage of reducing the phenomenon of electrostatic discharges in the planar radiating elements without significantly modifying the response of the radiating element subjected to an orthogonally polarized wave.