L-3 Communications Corporation

Unisys Corporation

Joseph Mark Baird

Bryant Ford Anderson

Rory Kim Sorensen

Richard Gerald Edwards

Paul Johann Gartside

Douglas Melville Harrison

Harry M Weinstein

Douglas H Ulmer

Charles Andrew Deneris

Mark Johnathon Yamamoto

Sterling Hardison Redd

Friedrich J Fisher

A radio frequency (RF) horn can include an interior surface with an inner geometry comprising irregular, aperiodic corrugations and/or undulations. The pattern of the inner geometry can excite higher order modes simultaneously in two RF signals each at a different frequency that combine with fundamental modes of the signals to produce substantially Gaussian profiles of the two signals at the output aperture of the horn. Even though the signals are at different frequencies, the illumination pattern of both signals on a reflector antenna at which the horn is directed can be substantially the same.

Dual-band feed horn

A radio frequency (RF) coaxial horn can comprise an inner RF horn disposed inside a larger outer RF horn. An interior surface of the inner horn can comprise a pattern of irregular, aperiodic features that excite modes in first and second RF signals each at a different frequencies that produce substantially Gaussian beam profiles of the first and second signals at the output aperture of the inner horn. The waists of the beam profiles of the first and second signals can be outside the inner horn but inside the outer horn. An interior surface of the outer horn and/or an outer surface of the inner horn can similarly excite modes in a third RF signal at a frequency different than the first and second RF signals to produce a substantially Gaussian beam profile of the third signal at the output aperture of the outer horn. The waist of the beam profile of the third signal can be aligned with the waists of the beam profiles of the first and second signals. Even though the signals are at different frequencies, the illumination pattern of the three RF signals on a reflector antenna at which the horn is directed can be substantially the same.

Tri-band feed horn

A splashplate antenna system configured using hybrid mode-matching techniques has improved secondary beam characteristics, including improved sidelobe performance, improved electric and magnetic plane correlation, reduced cross-polarization, improved electric and magnetic plane phase center correlation, and improved overall matching between the waveguide and the splashplate (sub-reflector). Internally, the waveguide contains a wall constructed from a series of varying dimensioned cross-sections that cause signals introduced to radiate in a multiple mode, Gaussian-like field pattern. The Splashplate is configured so that the waves received from the waveguide maintain the circular pattern symmetry, as well as other characteristics.

Splashplate antenna system with improved waveguide and splashplate (sub-reflector) designs

A feed system for an antenna has a set of inner and outer coaxial waveguides which apply, respectively, both higher and lower frequency radiations to a common radiating aperture provided by a horn and shroud which envelops radiating apertures of the individual feed waveguides. Each of the feed waveguides carries signals having a bandwidth of an octave. Lower frequency radiation to be transmitted by the outer coaxial feed waveguide is applied thereto by a set of four waveguides of a launcher which launches a wave with a desired propagation mode into the outer feed waveguide. Each of the launch waveguides is initially a rectangular double-ridged waveguide for increase bandwidth. The ridging is reduced to a condition of no ridging in the outer feed waveguide by a transition to a single inner ridge which terminates in a tapered star-shaped combination ridge within the outer feed waveguide. Impedance matching rings are slidable within the space between the inner and outer surfaces of the coaxial waveguide for development of a desired standing wave ratio for accurate generation of a desired beam pattern. A dielectric rod is disposed in a forward end of the tube of the inner feed waveguide and protrudes therefrom into the horn for shaping a beam of the higher frequency radiation. A single common phase center is provided for all bands with radiation simultaneously at plural bands.

Plural band feed system

Shrouded horn feed assembly

A single integrated antenna feed transmits and receives electromagnetic waves in the C, X, and Ku frequency bands. This antenna feed includes an inner metal tube which lies along a central axis, and an outer metal tube which surrounds and is coaxial with the inner metal tube. Through the inner tube, a passageway is provided which is sized to carry electromagnetic waves in the X-band and Ku-band, but reject electromagnetic waves in the C-band. Between the inner tube and the outer tube, another passageway is provided which is sized to carry electromagnetic waves in the C-band. An I/O port for the X and Ku-bands is provided by a first end of the inner tube, and an I/O port for the C-band is provided by a corresponding first end of the outer tube. This first end of the outer tube lies proximate to but not past the first end of the inner tube. A solid dielectric is inserted into and fills the first end of the inner tube; and, a hollow metal cone is attached to the first end of the outer tube.

Multi-band antenna feed with switchably shared I/O port

A dual frequency waveguide switch passes electromagnetic waves in the X-band along one route, and passes electromagnetic waves in the Ku-band along a different route. This switch includes a housing which has first, second, and third openings for the electromagnetic waves to pass through; and a movable member, mounted in the housing, having first and second passageways. The first passageway is shaped to pass electromagnetic waves in both the X-band and the Ku-band, and the second passageway is shaped to pass electromagnetic waves in the Ku-band but reject electromagnetic waves in the X-band. A forcing mechanism forces the moveable member to a position 'A' in the housing where the first passageway interconnects the first opening to the second opening, and to a position 'B' where the second passageway interconnects the first opening to the third opening.

Growing community of inventors

Sandy, UT, United States of America

Joseph Mark Baird