Abstract: A dual polarized mechanical scan antenna capable of rapid beam scanning includes a parabolic reflector having an elliptically shaped solid metal central section with conductive parallel grids extending therefrom to the perimeter of the paraboloid to form two outer grided sections. The axis of the parabolic reflector and the radiation axis of the feed antenna, positioned at the focus in alignment therewith, is positioned at a predetermined angle from a reference axis of the system. A polarization twist reflector is positioned at the focus for pivoting about the perpendicular to the reference axis. Dual polarization is realized when the twist plate is positioned such that the antenna system receives signals along paths that clear the parabolic reflector.

Abstract: A low profile, low drag, broad-banded antenna system includes four substantially identical antenna elements in intimate contact with a hemisphere of high dielectric constant material. The antenna elements are equally spaced from each other around the hemisphere and are connected to a power divider circuit for reception of incoming signals from a global position satellite having circular polarization. A dielectric phase equalizing member of variable thickness surrounds the antennas in intimate contact therewith for improving the axial ratio particularly at low angles of radiation. The dielectric phase equalizing member is also formed from a high dielectric constant material. A radome of a radio transparent material covers the assembly to provide an aerodynamic configuration and to protect the antenna from the weather. The antenna has a gain from approximately -2.5 dBic at 10.degree. above the horizon to approximately +3 dBic at 30.degree. above the horizon.

Abstract: A linearally polarized multiport multimode feed for a reflector type antenna generates a plurality of beams, each in a different pointing direction, from a single radiating aperture. Each beam possesses a distinct phase center determined by the waveguide modes establishing the aperture distribution for that beam. The feed is linear and bilateral, therefore may be utilized in a receiving or transmitting antenna.

Abstract: A circuit for use in connection with a meter for measuring the voltage standing-wave ratio (VSWR) along a transmission line wherein forward and reflected voltages in the transmission line are coupled off and detected by two respective diodes. Calibration of the two diode detected forward and reverse voltages occurs in a series of resistor-diode combinations before they are fed onto the base and collector, respectively, of a transistor. A meter connected between the collector and emitter of the transistor measures the voltage drop across the transistor and this value is proportional to the voltage standing-wave ratio.