An antenna, includes in part, a metal piece formed on a surface of a substrate and configure to radiate electromagnetic waves, a metal feed formed in the substrate and configure to supply electrical signal to the metal piece, and a multitude of metallic walls formed in the substrate and enclosing the metal piece. The antenna may be a patch antenna, a monopole antenna, or a dipole antenna. Each metallic wall may include a via that is fully or partially filled by a metal, or an electroplated tub formed in the substrate. The antenna further includes, in part, a metallic trace formed on the surface of the substrate and enclosing the antenna. The substrate may be a printed circuit board.