Abstract: A segmented transmission line used for the transfer of radio frequency energy in which the lengths of the individual segments are individually set to provide an optimally low reflection coefficient over specified frequency ranges.

Abstract: A dual-reflector microwave antenna includes a main reflector having a shape that is a portion of a paraboloid generated by revolution of a parabola around having a single, common axis of rotation and symmetry. A primary feed extends along the axis of the main reflector on the concave side of the main reflector, and a subreflector located beyond the end of said primary feed has an image-inverting surface configuration that has a ring focus located between the main reflector and the subreflector and extending around the axis of the main reflector. In either a single or dual-reflector antenna, the main reflector has a shield with a band of dielectric or conductive material extending around at least a portion of the inner surface of the shield for reducing the return loss of the antenna. Patterns may be improved by providing a shield of absorber material extending around the outer periphery of at least an end portion of the primary feed.

Abstract: A dual-reflector microwave antenna includes a main reflector having a shape that is a portion of a paraboloid generated by revolution of a parabola around having a single, common axis of rotation and symmetry. A primary feed extends along the axis of the main reflector on the concave side of the main reflector, and a subreflector located beyond the end of said primary feed has an image-inverting surface configuration that has a ring focus located between the main reflector and the subreflector and extending around the axis of the main reflector. In either a single or dual-reflector antenna, the main reflector has a shield with a band of dielectric or conductive material extending around at least a portion of the inner surface of the shield for reducing the return loss of the antenna. Patterns may be improved by providing a shield of absorber material extending around the outer periphery of at least an end portion of the primary feed.