A patch and a ground conductor are shortcircuited with two shortcircuit portions that are composed of conductive plates and that pass through a dielectric substrate. The shortcircuit portions are connected to the inner periphery of the patch and have large widths therealong. A first shortcircuit portion...http://www.google.ca/patents/US6124829?utm_source=gb-gplus-sharePatent US6124829 - Circularly polarized wave patch antenna with wide shortcircuit portion
