Abstract: An antenna system for an array antenna includes an array of radiators formed as patch antenna elements on a dielectric substrate, there being a shielding metallic sheet on a side of the substrate opposite the radiators. A further dielectric substrate and a bottom metallic sheet are disposed on a side of the shielding sheet opposite the radiators. An antenna feed system is disposed in the further sheet. Coupling devices such as orthogonal slots, in one embodiment, or a microwave crossover in a second embodiment, couple electromagnetic power from the feed system to the radiators through the shielding sheet. In the case of the coupling slots, the feed system provides phase quadrature signals for development of circularly polarized radiation. The crossover provides only a linearly polarized wave, and is formed of two coplanar waveguides, one in the shielding sheet and one in the bottom sheet.

Abstract: An antenna system includes an array of microstrip antenna elements wherein each of the elements includes two or more radiators. Electromagnetic signals are coupled from an input terminal of each element via one or more circulators which allow for application of an input signal to a first of the radiators followed by rerouting of respective signals to the next radiator. The radiators are turned to radiate at successively higher portions of the electromagnetic spectrum. By virtue of reflections of higher frequency radiation from a radiator tuned to a lower portion of the signal spectrum, each radiator radiates only that portion of the signal spectrum falling within the bandwidth of the radiator. By using three radiators, each antenna element is capable of radiating a signal spectrum three times as wide as are the bandwidths of a single radiator. Included within the antenna system is one or more power dividers to form one or more beams of radiation.