Hughes Aircraft Company

Gregory D Kroupa

Mon N Wong

Harold A Rosen

Krishnan K Raghavan

Harry Wong

Samuel S Wong

Robert C Perpall

Gary A Hill

Thomas F Foster, Jr

A circularly polarized wave entering the horn is converted to a linearly polarized wave which appears in one of the ports depending on the sense of the polarization. The stepped configuration of the impedance matching section minimizes mutual coupling among horns of the respective assemblies of the array antenna.

Horn radiator assembly with stepped septum polarizer

A flat cavity RF power divider wherein a flat cavity and an input waveguide share a common wall, coupling slots being disposed in the common wall offset from the centerline of the input waveguide for exciting a dominant TE.sub.4,0 mode in the flat cavity, the power divider also including short circuit means for exciting the transverse axis column of the flat cavity, and RF absorber means in the cavity to improve the frequency response of the divider, output coupling means also being provided for providing an RF power output.

Flat cavity RF power divider

A bicone microwave antenna having an orthomode tee as an input/output terminal, an internal dielectric polarizer, a circular waveguide with eight longitudinal radiating slots, two 30 degree conical reflectors, an external meanderline polarizer, and a partial circular waveguide short. An RF signal from the input/output terminal is converted into a rotating TE.sub.11 mode by the internal dielectric polarizer. The radiating slots in combination with the conical reflectors radiate the RF signal as a horizontally polarized field in a doughnut-shaped pattern. The meanderline polarizer converts the horizontally polarized field into a circularly polarized field. The partial circular waveguide short leaks a predetermined amount of radiation out the end of the waveguide to fill the center hole of the doughnut-shaped radiation pattern, thus producing a hemispherical RF beam having an elevation angle from 110 to -110 degrees. The use of impedance-matching circular rings in the waveguide further enhances the ability of the antenna to operate in three frequency bands.

Bicone antenna with hemispherical beam

A dual septum polarization rotator which, in the presently preferred embodiment thereof, includes a square waveguide and a pair of stepped septums disposed in spaced, orthogonal relation to each other within opposite end portions of the square waveguide. A first one of the septums extends horizontally between the side walls of the waveguide, parallel to the top and bottom walls of the waveguide, and the other/second one of the septums extends vertically between the top and bottom walls of the waveguide, parallel to the side walls of the waveguide. The first septum, in cooperation with the waveguide, defines first and second input ports, and, the second spectum, in cooperation with the waveguide, defines first and second output ports. The spacing between the first and second septums defines a central, open, nonseptum region within the waveguide. In operation, the first septum functions to convert the polarization of a first excitation signal introduced into the first input port from a first polarization to a second polarization, and the second septum functions to convert the second polarization into a third polarization orthogonal to the first polarization, for output, via the first output port, as a first output signal. For example, if the first polarization is horizontal polarization, then the second polarization is circular polarization, and the third polarization is vertical polarization. The polarization rotator of the present invention is also capable of dual mode operation, whereby the polarization of a second excitation signal introduced into the second input port is simultaneously rotated for output, via the second output port, as a second output signal.

Dual septum polarization rotator

A broad band omnidirectional monocone antenna 10 having a wide operative frequency spectrum and a large elevation angle A is disclosed herein. The antenna 10 of the present invention includes an input circular waveguide network 12 and 18 for providing electromagnetic energy of at least one polarization. Coupled to the circular waveguide network 12 and 18 is a dielectric-loaded waveguide arrangement 22 for projecting a first electromagnetic beam. The inventive antenna 10 further includes a parasitic element network 32, 34, and 36 positioned in the path of the first beam. The parasitic element network 32, 34, and 36 is disposed to form a parasitic beam in response to the first beam. In a particular embodiment of the inventive antenna 10 a beam shaping cone 40 circumscribes the dielectric waveguide arrangement 22. The cone 40 is adapted to augment the elevation angle A characterizing the antenna 10 of the present invention by redirecting the parasitic beam.

Broad band omnidirectional monocone antenna

A diplexer for electromagnetic signals of higher and lower frequency is formed of a common waveguide channel for both signals, the common channel branching into a through waveguide channel and a side waveguide channel. The through channel includes a filter having a pass band for propagation of the lower frequency signal and inhibiting propagation of the higher frequency signal. The side channel is formed as a waveguide below cut-off frequency with respect to the lower frequency signal for inhibiting propagation of the lower frequency signal while permitting propagation of the higher frequency signal. A coupling aperture formed as a slot resonant at the higher frequency is located in a waveguide wall at an integral number of quarter guide wavelengths in front of the filter for coupling the higher frequency signal between the common and the side channels.

Microwave diplexer

A polarization selector system, suitable for use with an antenna for radiating electromagnetic waves at a variety of preselectable polarizations, is formed of an orthogonal mode launcher of electromagnetic waves, and a hybrid coupling assembly for driving the launcher. The coupling assembly has a pair of waveguides sharing a common wall. A set of hybrid couplers of differing coupling ratios, and including a mechanically displaceable gate within each coupler, is disposed serially along the common wall. The gates are individually positionable to provide for coupling of differing amounts of electromagnetic power with 90 degree phase shift between the waveguides. Output signals of the waveguides connect with respective ones of a pair of mode launching probe assemblies in the mode launcher to energize the probe assemblies for producing a resulting electromagnetic wave having selectively right and left hand circular or elliptical polarization as well as linear polarization which can be advanced in orientation in increments of ninety degrees.

Growing community of inventors

Hawthorne, CA, United States of America

Gregory D Kroupa