Abstract: An improved microstrip antenna device, in particular for telephone transmissions by satellite. An antenna comprises a first dielectric layer including on one side a ground plane and on the other a first conductive patch of a chosen shape, a second dielectric lalyer surmounts the first dielectrica layer on the side adjacent to the first patch and supports, on the other side remote from the first patch, a second cnoductive patch of a chosen shape. A third dielectric layer surmounts the second. The second patch is of a size smaller than that of the first patch and this first patch is fed from below at at least one chosen point situated between its center and its circumference. Advantageously, the first patch is connected to a lead-in of the ground plane joining a feeding circuit implanted in a dielectric substrate of a three-plate structure.

Abstract: A microstrip antenna device having a dielectric layer, a conductive patch of a chosen shape on one side of the layer and, on the other side of the layer, a conductive plate forming a ground plane; and, a feed circuit comprising at least one microstrip line connected to the conductive patch and implanted in the dielectric layer in the same plane as the conductive patch. The thickness of the dielectric layer opposite the microstrip line is greater than the thickness opposite the periphery of the microstrip line. Further, the thickness of the dielectric layer opposite the conductive patch is greater than the thickness opposite the microstrip line, and also greater than the thickness opposite the periphery of the conductive patch.