Abstract: A dual frequency cavity backed slot antenna and method of tuning the antenna, wherein the antenna comprises a plurality of stacked layers including a layer having a substrate with an accessible surface, the surface including thereon a continuous slot, first electrically conductive metallization disposed within the slot and extending to the slot, second electrically conductive metallization disposed external to the slot and at least one pair of frequency adjusting devices, one such device associated with the first metallization and the other device associated with the second metallization. The device pairs are either a foil and a tab, a pair of foils or a pair of indentations, one in each of the metallizations.

Abstract: A dual frequency cavity backed slot antenna and method of tuning the antenna, wherein the antenna comprises a plurality of stacked layers including a layer having a substrate with an accessible surface, the surface including thereon a continuous slot, first electrically conductive metallization disposed within the slot and extending to the slot, second electrically conductive metallization disposed external to the slot and at least one pair of frequency adjusting tabs, one tab coupled to the first metallization and the other tab coupled to the second metallization. The tabs are electrically conductive metallization, the tab coupled to said first metallization extending outwardly toward the second metallization and the tab coupled to the second metallization extending inwardly toward the first metallization. A slot is provided between the tab coupled to the second metallization and the second metallization. Each tab of a pair is coaxial with the other tab of the pair and symmetrical about the axis.

Abstract: An antenna system and method comprising an antenna having 2+N antenna elements, where N is zero or an odd integer, an algorithm controlled switching circuit having a separate switch associated with each of the elements and a switch control selectively causing the switching circuit to couple an adjacent pair of the antenna elements to their associated switches while maintaining the remaining switches uncoupled from their associated antenna elements. The algorithm controlled switch control includes circuitry for successively coupling each adjacent antenna element pair of the antenna elements to their associated switches, determining a predetermined parameter for each of the antenna element pair and then causing the antenna system to operate with only one of the antenna pairs responsive to determination of the predetermined parameter.