Abstract: A system and method for providing wireless communication services to passengers of an aircraft through the use of a standard mobile telephone. A system of antennas on an air base station radiates above a horizontal plane in order to provide coverage for an aircraft flying through a service airspace. The air system may be conveniently overlaid on an existing terrestrial wireless system in order to share based station facilities. A stretched dome shaped antenna pattern provides 360 degrees of coverage in the horizontal plane. A cardioid direction antenna pattern in the horizontal plane provides coverage in a specific portion of the air space such as an air corridor. Various combinations of antennas, and transceivers are interconnected in order to provide the proper coverage, capacity and interference control requirements for a particular air cell.

Abstract: A phased array antenna having a plurality of independent antenna modules which are arranged in a manner to significantly improve cross polarization isolation of the antenna. The antenna modules are arranged in rows and columns to form a grid arrangement. Each antenna module has a pair of radiating elements, and each module is rotated 90° from its adjacent antenna modules in each column. In this manner, the worst case cross polarization isolation performance of each module is not summed together at the same azimuth scan angle as every other module but rather is broken up over the entire azimuth scan angle.

Abstract: A multi-beam antenna system including a parabolic reflector with a parallelogram perimeter, which is illuminated by a plurality of feed elements; so that the parabolic reflector reflects a first beam corresponding to one frequency that illuminates a first parallelogram spot, a second beam corresponding to the same frequency that illuminates a second parallelogram spot, such that the first and second spots are parallelepiped arranged one un-adjacent another of the same frequency are generally un-adjacent.

Abstract: A multibeam antenna for receiving and transmitting microwaves from satellites comprises a parabolic reflector (12) with parallelogram rim and a plurality of feed elements (13) which are located alongside one edge of the reflector (12) close to focus with minimum distance to the center of the reflector (12). The feed elements (13) are arranged along lines close to 45, 135, 225, 315 degree from main axes of parallelogram rim.

Abstract: A system for communicating between computers that are at a number of different locations in a large multi-story building in which radio transmission is achieved through stairwell shafts and through windows along a zone outside of the building. This system employs communication through spread spectrum transceivers and a set of directional antennas. At each station, one of the antennas is circular polarized and the other is linear polarized with a horizontal electrical component to facilitate reflection off the floors of the building. The spread spectrum is a hybrid frequency hopped and direct sequence modulated signal.

Abstract: A high-frequency, e.g., microwave, antenna (100) is stamped from a single sheet (300) of electromagnetically conductive material, e.g., a metal plate. A manufacture comprising a frame (104), a plurality of radiator antenna elements (108), a plurality of first supports (112) each connecting a radiator antenna element to the frame, a feed network (110) connected to the radiator antenna elements, and a plurality of second supports (304) connecting the radiators and the feed network to each other and to the frame, are stamped out of the single sheet. A combiner (114) may be included in the manufacture as well. The second supports provide alignment and rigidity during manufacture and assembly. Preferably, a plurality of the manufactures are stamped out side-by-side from a single roll (400) for ease of automated manufacture and assembly.

Abstract: A common aperture reflector antenna and feed are provided for use in common aperture sensor systems. The feed includes an array of individual elements. The array elements are configured to increase the overall efficiency of a reflector antenna by flattening the aperture illumination, and also by nullifying the illumination within the centrally-blocked-portion of the reflector antenna surface. More specifically, the array elements are carefully configured with respect to spacing and excitation, for example, such that the array illuminates only the non-blocked portion of the main reflector. In addition, the array pattern is optimized such that the non-blocked portion of the reflector antenna is quasi-uniformly illuminated.

Abstract: An antenna array includes two acutely bent dipole antenna elements placed back-to-back on a printed circuit board with integrated micro-strip balun transformers which a Wilkinson divider drives 180 degrees out of phase. In an embodiment, the antenna array sits on a vertical blade support structure to form a T-Top section.

Abstract: A multi-feed, multi-band antenna includes a parabolic dish reflector, a plurality of four-port feeds, and may also include one or more orthomode two-port feeds. Each four-port feed is constructed to conduct multiple frequency bands and multiple polarized RF signals within each of the bands. A mounting structure mounts each of the feeds at a different position in a line and in a plane parallel to the rim of the reflector. The four-port feeds are of a size which allows them to be mounted adjacent each other and two degrees apart. The mounting structure positions the feeds at a distance F from the reflector. The diameter D of the reflector and the distance F have a relationship such that F/D is less than approximately 0.5.

Abstract: An antenna system has a reflector illuminated by a primary feed for producing a primary beam. The reflector is illuminated further by a secondary feed formed of an array of secondary feed elements of which the respective electromagnetic signals are adjustable in terms of their relative amplitudes and phases to produce a secondary beam with sidelobes oriented in directions away from the directions of the primary beam. Spacing among feed elements of the secondary feed array is selected for further control of orientation of sidelobes of the secondary beam. Highest efficiency is attained for signals of the primary feed by configuring the reflector for forming the primary beam, while the secondary beam is produced with lower efficiency but with isolation from the primary beam. The surface of the reflector is contoured to provide maximum primary-beam efficiency and minimal primary-beam sidelobes in the direction of the secondary beam.

Abstract: An antenna comprising the following members are provided: a first board-shaped dielectric material; a cylindrical member, provided on one face of the first board-shaped dielectric material, in which a part of a side wall may be cut off; plural second board-shaped members provided as radiating on the outer surface of the cylindrical member, one end face of each second board-shaped member being in contact with the surface of the first board-shaped dielectric material; and plural sets of plural pole members perpendicular to the surface of the first board-shaped dielectric material, made by forcing out corresponding portions of the first board-shaped dielectric material, the sets radiating from the outer surface of the cylindrical member and the plural pole members in each set being arranged in a line, and each set existing between two positional directions of the adjacent two second board-shaped members.

Abstract: A passive reflective antenna located near an active receiving antennas is used to change the energy at the receiving antenna. The change in energy may be such as to remove a null created by multipath or to provide directionality, or both. The receiving antennas is permanently connected to a single receiver. When the receiver's output signal degrades below an acceptable level of quality, the reflective phase of the passive antenna's load is changed to change the phase of the reflected energy and achieve a desired effect (remove a null, change directionality, etc.) at the receiving antenna. In the simplest embodiment, the termination of the passive antenna is switched from an open circuit to a short circuit, or vice versa, to invert the phase of the reflected energy. The use of reflective elements in antenna designs, usually to achieve directionality, is well known (see the common Yagi or corner reflector antenna designs, for example), but these use passive reflector elements.

Abstract: An antenna for broadcasting omnidirectionally is disclosed. The antenna includes a cylindrical housing which has a lip which includes slots adapted to receive a patch antenna strip and a conductive ring. A GPS receiver and electronics package may be placed in the center of the housing. The patch antenna strip which includes a number of patch antennas broadcasts and receives radio signals. The conductive ring absorbs energy broadcast from the patch antennas and rebroadcasts the signal omnidirectionally. The resulting signal has a high gain and a wide bandwidth. A third embodiment in which the conductive ring is incorporated into a housing cover is also disclosed. The antenna is easily and inexpensively assembled and is more durable and reliable than prior art antennas.

Abstract: A shaped beam antenna system which provides a desired shape of beam, comprises a reflector and at least one primary radiator located essentially at focus of said reflector. Reflection surface of the reflector is a dense set of parabolas in which vertexes of said parabola shift on a predetermined locus which is preferably a three dimensional space curve, but not a plane curve. A second feature of the shaped beam antenna system is the primary radiator which is composed of a plurality of primary radiators positioned closely to each other.

Abstract: A radio direction finding antenna system including four identical radiating elements uniformly distributed on a circle around a conductive mast and designed to determine the angle of incidence of the propagation direction of a plane electro-magnetic wave relative to a reference direction, wherein the radiating elements are associated in first and second pairs of opposite radiating elements in which the elements are inverted relative to each other, and wherein the antenna system includes a processor unit comprising firstly a first matched power halver receiving the signals provided by the first pair of radiating elements and a second matched power halver identical to the first and receiving the signals provided by the second pair of radiating elements, and secondly a 3 dB-90.degree. type hybrid junction receiving the signals delivered by the matched power halvers and providing two output signals at a phase difference of 2.theta.-1/2.pi.. The invention is applicable to radio location.

Abstract: An array antenna is shown, the disclosed antenna having an effective cross-sectional area which is lower than its physical cross-sectional area. The reduction in effective cross-sectional area is effected by: (a) fabricating the reflector for the array antenna from spaced wires; and, (b) curving the entire array and its reflector.

Abstract: A relatively broadband printed circuit antenna structure includes a dielectric sheet having printed circuit-like conductive structures printed on both sides in predetermined registration with one another. A traditional non-radiating microstrip transmission line structure extends from a common r.f. feedpoint to at least one terminal end portion. However, apertures disposed within the underlying (or overlying) conductive reference surface of the double-cladded printed circuit board in the vicinity of each terminal end cause substantial r.f. radiation to occur over a relatively broader bandwidth than with a more traditional microstrip antenna radiator structure. In one embodiment, the aperture in the microstrip ground plane itself becomes a radiating aperture due to the transmission line currents flowing within the ground plane.

Abstract: An antenna for CP signals uses a reflector, such as a truncated pyramid. Feed tubes, which act as a balun extend from the pyramid. Four truncated square loops are coupled to the feed means. The truncation results in a smaller radome being used and hence smaller wind resistance. A feed strap has a capacitance hat for a better match.

Abstract: A dished reflector is illuminated by a primary radiation feed including a rectangular waveguide and a secondary radiation feed comprising two dipoles flanking that waveguide. In order to minimize distortion of the radiation diagram from the secondary feed by the waveguide envelope, at least one elongate corrective member paralleling the dipoles is externally mounted on that envelope and is capacitively coupled or conductively connected thereto at a location where a peripheral current induced by the dipoles is at a maximum. The corrective member, like the dipoles themselves, may be a plate with major faces lying in planes perpendicular to the waveguide axis.

Abstract: An antenna assembly with a curved reflector and feed means at one side of the focal axis of such reflector. The feed means includes a number of relatively-fixed-position feed elements spaced apart unequally to obtain signals of different phase at the reflector for forming a composite reflected beam with minimized sidelobe content.

Abstract: An antenna system for broadcasting comprises a coplanar array of three vertical aerials spaced a quarter wavelength apart, the middle aerial serving as a passive reflector while the outer two are concurrently energized with currents of equal amplitude and frequency in phase or in phase opposition with each other. The resulting radiation pattern is circular in the first instance; in the second case the pattern is generally hourglass-shaped and bisected by the common plane of the aerials.