Patent ID: 8350767

Claim:
An array antenna comprising: a planar substrate disposed parallel to a substrate plane and having a first conductive layer, a second conductive layer, and at least three dielectric layers disposed between the first and second conductive layers, each adjacent pair of the dielectric layers having a planar interface defined therebetween; a plurality of notch antenna elements each having a base and a vertical section having a notch therein, the base and vertical section each extending perpendicular to the substrate plane, the base having a base cavity defined as an opening that extends through the base and perpendicular to the substrate plane, each of the notch antenna elements being disposed so that the base is on top of the first conductive layer at an opening therein; a plurality of coupling striplines disposed below the first conductive layer and electrically coupled at an end to the first conductive layer, each of the coupling striplines configured to couple a radio frequency (RF) signal between the coupling stripline and a respective one of the notch antenna elements; a plurality of RF vias each electrically coupled to an opposite end of a respective one of the coupling striplines and extending through at least one of the dielectric layers to one of the planar interfaces; and a plurality of distribution striplines each disposed in one of the planar interfaces below the coupling striplines, wherein each of the distribution striplines is electrically coupled to one of the RF vias in a respective one of the planar interfaces.