Highly-directive aperture-coupled microstrip patch antenna based on planar meta-surface

Since the discovery of metamaterials, one of the potential applications of such structures has been the development of substrates and superstates for planar antennas. Recently, a meta-surface composed by grids of capacitively loaded and continuous wires has been implemented as superstate and substrate of a dipole antenna, with the consequent improvement of its radiations properties, The main advantages of this meta-surface are its low profile, (since the metasurface is directly illuminated by the antenna, and no cavity is required), reduction of coupling between radiating elements in antenna arrays, as well as ease of integration of active components. However, in order to transfer this concept adequately to smart antenna technologies, it is convenient to adapt the meta-surface to the use of microstrip antennas, which are of great popularity among antenna arrays. Therefore, this article addresses the design of an aperture coupled microstrip rectangular patch antenna covered by a planar meta-surface.