US Patent 7363058 Wireless point multipoint system

A patch array antenna includes a planar base on which is defined a ground plane and feed positions that are electrically isolated from the ground plane. A plurality of patch elements are configured to resonate over a predetermined frequency range. Each patch element is isolated from the ground plane and disposed on the base over the ground plane so that an air dielectric is defined between the patch element and the ground plane. Each patch element defines a resonant portion that is electrically connected to a respective feed position. A feed network is defined on the base that electrically connects the feed positions to one or more output points on the base.