Abstract: A low-loss vehicle communications system including a stationary radiating cable antenna and a slotted array antenna, either of which may be operated as transmitting and/or receiving antennas. The radiating cable antenna includes a plurality of apertures designed to produce a radiated field having a defined phase front in response to excitation of the antenna. The slotted array antenna is mounted to a vehicle movable in an axial direction along a length of the stationary radiating cable antenna. The slotted array antenna includes a corresponding plurality of slots which are oriented so as to couple to the radiated field along a phase front substantially matching the phase front of the radiating cable antenna.

Abstract: A television broadcast invention comprising an elongated vertical support, a plurality of transmission lines extending upwardly along the vertical support, a plurality of primary radiators spaced along the length of the vertical support and connected to the transmission lines for radiating vertically polarized signals, and a plurality of parasitic radiating elements disposed radially outwardly from the primary radiators for re-radiating the vertically polarized signals as elliptically polarized signals. The primary radiators are preferably open-sleeve dipoles mounted on and surrounding a central hollow mast and fed by transmission lines extending along the hollow interior of the mast.

Abstract: An omnidirectional microwave antenna comprises a conical reflector and a conical feed horn. The conical reflector has a reflecting surface defined by a cone having an axis and a surface of revolution around the axis. The line of intersection between the surface of revolution and a plane passing through the axis and the surface of revolution is a segment of a parabolic curve. The reflector includes a flange extending outward from an outermost circumference of the surface of revolution of the cone. The conical feed horn feeds microwave energy to the conical reflector from a location along the axis of the cone. The feed horn has an aperture whose center is located approximately at the apex of the cone. The flange has absorptive material mounted thereto for absorbing microwave energy impinging thereon.

Abstract: An improved radio frequency antenna may be manufactured and assembled in a cost-effective manner using a pair of conductive sections. A first conductive section has alternating trough and narrow portions, and an opposing second conductive section has alternating trough and narrow portions which are arranged opposite the narrow and trough portions, respectively, of the first conductive section. Each trough portion partially surrounds its opposing narrow portion. The first and second conductive sections are secured together with a gap formed therebetween such that the first and second conductive sections form an elongated unit having a first end and a second end. Each end of the unit may be terminated with a short, an open or a load between the first and second conductive sections, and a coaxial cable may be electrically coupled to the first and second conductive sections at a selected point along the length of the unit for coupling a radio frequency signal to the antenna.

Abstract: A patch antenna having a dielectric substrate; a plurality of radiating patches on the substrate, each radiating patch including a plurality of spaced slots to suppress the radiation of energy that is polarized in a direction transverse to the direction of the desired polarization; a ground plane supported by the substrate in generally parallel and spaced relationship to the patches; a distribution network for transmitting and receiving signals within the antenna; and a plurality of probes within the substrate for coupling the radiating patches and the distribution network, one end of each probe being connected to the distribution network, and the other end of the probe being coupled to one of the radiating patches. In a preferred embodiment, a plurality of chokes are connected to the ground plane and associated with the patches to further suppress the radiation of energy having undesired polarization.

Abstract: An antenna for elliptically polarized television transmission comprising, an elongated cylindrical waveguide having a multiplicity of slots spaced along the length and around the circumference of the waveguide for radiating horizontally polarized energy; a multiplicity of parasitic radiating dipoles mounted on the outer surface of the waveguide and spaced along the length and around the circumference of the waveguide for radiating vertically polarized energy, each of the dipoles being associated with one of the slots so that the combination of the horizontally and vertically polarized radiation produces elliptically polarized radiation; couplers for coupling electromagnetic energy from the interior of the waveguide to the slots; and a pair of coupling capacitors on opposite sides of each slot and connected to the radiating elements of the associated dipole for coupling electromagnetic energy from the field around the slot into the respective radiating elements.

Abstract: A UHF-TV broadcast system comprising an antenna mounted on an elevated supporting structure for broadcasting UHF-TV to a prescribed region, and a transmission line having a horizontal run leading to the supporting structure for the antenna, and a vertical run leading to the antenna, the transmission line comprising a circular non-coaxial waveguide having an inside diameter large enough to support the propagation of electromagnetic energy therethrough in at least the circular, non-coaxial TE.sub.11 mode, and a multiplicity of conductive elements extending transversely across the interior of the waveguide at intervals along the length of the waveguide perpendicular to the electric field vector of TE.sub.11 -mode energy having a desired polarization, for suppressing unwanted TE.sub.11 -mode energy that is cross-polarized relative to the desired polarization.

Abstract: An antenna for circularly polarized television transmission comprising, an elongated coaxial waveguide having inner and outer conductors, the outer conductor of the waveguide having a multiplicity of slots spaced along the length and around the circumference of the outer conductor for radiating horizontally polarized energy, a multiplicity of dipoles mounted on the outer surface of the outer conductor and spaced along the length and around the circumference of the outer conductor for radiating vertically polarized energy, each of the dipoles being associated with one of the slots so that the combination of the horizontally and vertically polarized radiation produces circularly polarized radiation, and coupling means for coupling electromagnetic energy from the interior of the waveguide to the slots and the dipoles, the coupling means for both the slots and the dipoles picking up electromagnetic energy from the interior of the waveguide in a common transverse place.

Abstract: A high-power, end-fed, circular, non-coaxial waveguide UHF-TV broadcast antenna comprising a single-moded, circular, non-coaxial waveguide having an inside diameter dimensioned to support only the circular non-coaxial TE.sub.11 mode of energy propagation through the waveguide at the design frequency of the operating frequency band, the waveguide having multiple radiating elements removing energy from the waveguide at intervals along the length of the waveguide, and conductive means extending transversely across the interior of the waveguide at least in the regions between longitudinally adjacent pairs of the radiating elements, the conductive means being perpendicular to the electric field vector of the TE.sub.11 -mode energy having a desired polarization, for suppressing TE.sub.11 -mode energy that is cross-polarized relative to the desired polarization, the waveguide and the conductive means defining a feed port at one end of the waveguide for receiving UHF-TV signals having the desired polarization.

Abstract: A device for providing a low VSWR match at a bend between two straight circular waveguides has an odd number of at least three circular waveguide sections of approximately equal length along their axes mitered at both of their ends, the length chosen to be an odd multiple of a quarter guide wavelength at the desired operating frequency, and the waveguide sections being mitered so that the device is symmetrical about the bisecting plane of the bend. The ratios of the angles between the adjacent waveguide sections around the bend are approximately binomial coefficients in order to obtain a maximally flat passband.