Abstract: A stacked array antenna system is presented having one or more antenna(s) as part of the supporting structure. This allows more than a single omni-directional antenna to be used with a minimum amount of azimuth pattern degradation. At least one antenna is actually part of the structure. By placing the antenna(s) in the structure, the antenna structure becomes a structural platform for one or more other antenna(s).

Abstract: An omnidirectional microwave antenna comprises a paraboloidal reflector disposed above the ground and facing downwardly with a substantially horizontal aperture and a substantially vertical axis. A vertically oriented feed horn is located below the paraboloidal reflector on the axis of the paraboloidal reflector and has a phase center located near the focal point of the paraboloidal reflector. A conical reflector having a shaped reflecting surface defined by the parameters of a mathematical equation extends downwardly away from the periphery of the feed horn for reflecting radiation received vertically from the paraboloidal reflector in a horizontal direction away from the conical reflector, and for reflecting horizontally received radiation vertically to the paraboloidal reflector.

Abstract: An omnidirectional microwave antenna comprises a paraboloidal reflector disposed above the ground and facing downwardly with a substantially horizontal aperture and a substantially vertical axis. A vertically oriented feed horn is located below the paraboloidal reflector on the axis of the paraboloidal reflector and has a phase center located near the focal point of the paraboloidal reflector. A conical reflector having a shaped reflecting surface defined by the parameters of a mathematical equation extends downwardly away from the periphery of the feed horn for reflecting radiation received vertically from the paraboloidal reflector in a horizontal direction away from the conical reflector, and for reflecting horizontally received radiation vertically to the paraboloidal reflector.

Abstract: A rigid, coaxial transmission line is provided which includes a plurality of sections joined by connector assemblies. The transmission line includes a plurality of ordered groups. Each of the ordered groups includes a plurality of equal-length sections. The length of the equal-length sections in each ordered group is selected to reduce the VSWR spikes caused by the connector assemblies. The length of the equal-length sections progressively changes between each of the ordered groups.

Abstract: A radiating coaxial cable comprises an inner conductor, a layer of cellular foam dielectric material surrounding the inner conductor, and a single, continuous, corrugated outer conductor surrounding the dielectric foam layer in direct contact with it. The outer conductor forms at least one row of slots which are configured to produce a radiated field polarized perpendicularly to the axis of the cable to substantially avoid the radiation of a field polarized parallel to the axis of the cable and to provide coupling energy between the interior of the cable and the slots. In this way a substantially constant near-field pattern is produced along the length of the cable across the bandwidth of the cable.

Abstract: A radiating waveguide comprises an elongated waveguide with a transverse cross-section dimensioned to carry only the dominant mode at a selected operating frequency. One wall of the waveguide forms a continuous non-resonant longitudinal slot or equivalent thereof to produce a radiated field polarized perpendicularly to the slot. The slot extends substantially parallel to the axis of the waveguide and has a transverse dimension that is sufficiently narrow to substantially avoid the radiation of a field polarized parallel to the slot.

Abstract: A microwave antenna comprising the combination of a paraboloidal main reflector; a subreflector located such that the paraboloidal main reflector and the subreflector have a common focal point lying between the main reflector and the subreflector; a feed horn for transmitting microwave radiation (preferably symmetrically) to, and receiving microwave radiation from, said subreflector; and a shield connected to the peripheral portion of the subreflector and having an absorbing surface which reduces side lobe levels both by capturing the feed horn spillover energy and by reducing the diffraction of microwave radiation from the edge of the subreflector. The shield is preferably formed as a continuous axial projection extending from the periphery of the subreflector toward the main reflector substantially parallel to the axis of the feed horn. The reflective surface of the subreflector is suitably a section of an approximate ellipse.

Abstract: A combiner for transmitting and receiving co-polarized microwave signals in a selected propagation mode in at least two different frequency bands, the combiner comprising a main waveguide dimensioned to simultaneously propagate signals in the different frequency bands, at least a portion of the main waveguide being overmoded; at first and second junctions spaced along the length of the main waveguide for coupling signals in the different frequency bands in and out of the main waveguide, at least the first junction being located in an overmoded portion of the main waveguide and having side-arm waveguide means associated therewith for propagating signals in one of the different frequency bands; filtering means disposed within the main waveguide and operatively associated with the first and second junctions, the filtering means having (1) a stopband characteristic for coupling signals in a first one of the frequency bands between the main waveguide and the first junction and the side-arm waveguide means associat

Abstract: A horn-reflector microwave antenna has a reflector plate which is a section of a paraboloid, and a flared feed horn for supplying microwave signals to the reflector plate. The horn has a conical section forming a circular aperture at the wide end, which is the end closer to the reflector plate, and a pyramidal section forming a square aperture at the narrow end, which is the end farther away from the reflector plate. Microwave signals are supplied to the feed horn with the electrical field extending along a diagonal of the square aperture.

Abstract: A feed horn for a reflector-type microwave antenna comprises a smooth-walled conical horn and a lining of absorber material on the inside wall of the horn for reducing the width of the RPE (radiation pattern envelope) in the E plane of the antenna. The lining of absorber material extends from the wide end of the conical feed toward the narrow end thereof, terminating at a point where the horn diameter is about 7 times the longest wavelength of the microwave signals being transmitted. The width of the RPE in the E-plane of the antenna can be reduced to be nearly equal to the width of the RPE of the H-plane of the antenna without significantly degrading this H-plane RPE from its shape without absorber and without significantly changing the gain of the antenna.