Abstract: A corrugated feed horn for antenna has an oval pattern of corrugations, and a series of intermediate ridges spaced between adjacent corrugation ridges only in the regions of the slots near its major axis. The intermediate ridges provide a feed horn that is capable of producing a relatively uniform oval beam, and has enough corrugations per wavelength to guarantee little diffraction on the edges of the horn, thus resulting in an antenna with very low side lobes.

Abstract: A corrugated feed horn for antenna has an oval pattern of corrugations, and a series of intermediate ridges spaced between adjacent corrugation ridges only in the regions of the slots near its major axis. The intermediate ridges provide a feed horn that is capable of producing a relatively uniform oval beam, and has enough corrugations per wavelength to guarantee little diffraction on the edges of the horn, thus resulting in an antenna with very low side lobes.

Abstract: An antenna has a waveguide horn extending from a main reflector. A dielectric tube extends from the distal end of the waveguide horn to support a sub-reflector in the focal region of the main reflector. An insert is placed into the dielectric tube to seat against the distal end of the dielectric tube. A fastener secures the insert to the sub-reflector, thereby securing the sub-reflector to the distal end of the dielectric tube. The surface of the insert serves as a continuation of the sub-reflector. The dielectric tube can be equipped with an inwardly-extending collar about its distal end to engage the insert.

Abstract: An antenna includes a main reflector with a focal circle about an axis. A waveguide horn extends from the main reflector along this axis. A sub-reflector is mounted beyond the distal end of the waveguide horn with an annular gap remaining between the sub-reflector and the distal end of the waveguide horn. The annular gap forms a radial transmission line between a first wall on the sub-reflector and a second wall having outer annular corrugated surfaces on the distal end of the waveguide horn. The first wall of the transmission line is a body of revolution of elliptical shape on the sub-reflector. This ellipse is tilted at an angle with respect to the axis, and has a first focal point on the axis. The other focal point is preferably on or near the focal circle. The phase center of the waveguide horn does not coincide with either foci.

Abstract: An antenna includes a main reflector with a focal circle about an axis. A waveguide horn extends from the main reflector along this axis. A sub-reflector is mounted beyond the distal end of the waveguide horn with an annular gap remaining between the sub-reflector and the distal end of the waveguide horn. The annular gap forms a radial transmission line between a first wall on the sub-reflector and a second wall having outer annular corrugated surfaces on the distal end of the waveguide horn. The first wall of the transmission line is a body of revolution of elliptical shape on the sub-reflector. This ellipse is tilted at an angle with respect to the axis, and has a first focal point on the axis. The other focal point is preferably on or near the focal circle. The phase center of the waveguide horn does not coincide with either foci.

Abstract: An antenna has a waveguide horn extending from a main reflector. A dielectric tube extends from the distal end of the waveguide horn to support a sub-reflector in the focal region of the main reflector. An insert is placed into the dielectric tube to seat against the distal end of the dielectric tube. A fastener secures the insert to the sub-reflector, thereby securing the sub-reflector to the distal end of the dielectric tube. The surface of the insert serves as a continuation of the sub-reflector. The dielectric tube can be equipped with an inwardly-extending collar about its distal end to engage the insert.