Abstract: An efficiently radiating helical antenna includes a conductive helix receiving signals to be radiated at a first end of the conductive helix device for capacitively pulling fields generated by the signals towards a second end of the conductive helix opposite the first end. The device may be a conductive tube inserted into the second end of the conductive helix or a disjointed conductive helix surrounding the conductive helix. This scheme works especially well for a conductive helix having a circumference on the order of one wavelength.

Abstract: A dual polarized flat plate antenna structure has a single circular waveguide output accommodating probes for separate orthogonally polarized signals. A housing to be affixed to the antenna structure contains a low noise block having a single circular waveguide input with complementary probes. The housing is rotatable relative to the antenna structure about the common axis of the waveguides. The low noise block incorporates switching means for selectively coupling the output signals of the antenna array structure with a common low noise block input circuit. Rotation of the low noise block enables the angle of the polarizing coupling between the array output probes and the low noise block input probes to be varied.

Abstract: A multi-element directional antenna and process for making same are described. The antenna comprises a lightweight dielectric substrate having an array of parasitic elements disposed on the substrate. A printed circuit board having a ground plane on one side thereof, and a driven element and phasing means comprising a hybrid (magic-or-twin) tee junction on the other side thereof, disposed coplanar with the parasitic elements and the substrate. The multi-element directional antenna, may be formed using low labor cost manufacturing process such as stamping and laminating, and additive and/or subtractive (i.e. etching) techniques.

Abstract: A corner reflector antenna array capable of being driven by a coaxial feed line is disclosed herein. The antenna array comprises a substantially right-angle corner reflector having first and second reflecting surfaces. A dielectric substrate is positioned adjacent the first reflective surface, and defines first and second opposing substrate surfaces. In the preferred implementation the dielectric substrate is oriented substantially parallel to, but spaced from, the second reflective surface. The antenna array further includes a plurality of dipole elements, each of the dipole elements including a first half dipole disposed on the first substrate surface and a second half dipole disposed on the second substrate surface. A twin line interconnection network, disposed on both the first and second substrate surfaces, carries signal energy to and from the plurality of dipole elements.

Abstract: A dual polarization antenna includes a non-conducting space surrounded by a ground plane. Two angularly offset sets of dipole structures penetrate into the space. Each set of dipole structures comprises a pair of aligned short circuit elongate dipoles extending from the ground plane into the space from diametrically opposed directions and terminating in respective free ends. The free ends are adjacent, but spaced from each other, to define a gap between them. At least one separate device is provided for exciting each set of dipole structures or each dipole structure within a set individually. A radiating element is provided overlying the dipole structures such that the dipole structures couple, in use, with the radiating element, causing the radiating element to radiate polarizations determined by the orientation of each of the sets of dipole structures.

Abstract: Microwave devices incorporate at least one photosensitive baffle that is selectively illuminated, changing the baffle's electronic characteristic from being transparent to microwave energy to being reflective thereof. That action selectively alters an electronic characteristic of the microwave device. The effect is shown applied in a number of devices, including a back lobe antenna. Undesired back lobes occuring at a principal frequency are reduced in a back plane antenna by alternately coupling and decoupling an extension to the antenna's back plane at a rate sufficiently high enough to shift the back lobes to adjacent frequencies. A photoelectrically controlled baffle suitably serves as the extension.

Abstract: A multi-element, H plane, phased, dipole array antenna has a high gain over a wide angle in azimuth and over a controlled sector in elevation. Two printed wiring boards feed and physically support the dipole antenna elements. The phase and spacing of the dipole elements establish the radiation elevation angle, and a planar metallic reflector, spaced on the order of a half wavelength of the RF signal from the dipole array, interacts with the dipole-element pattern, to provide the wide angle azimuth gain.

Abstract: Multi-beam antennas with relatively large effective apertures for high antenna gain are provided for tower or pole mounting for cellular and other uses. Low wind resistance is achieved by use of thin cylindrical radiating units and thin cylindrical tuned reflector units. Each radiating unit includes separately excited upper and lower radiators, each including a microstrip pattern of a phase reversed series of half-wave transmission line sections on a substrate enclosed in a fiberglass tube radome. Each tuned reflector unit includes a resonant stack of electrically isolated metal rods enclosed in a fiberglass radome. In one embodiment, four cylindrical radiating units, each including upper and lower radiators, are laterally spaced in front of upper and lower reflector configurations, each including seven laterally spaced tuned reflector units.

Abstract: The disclosure relates to broadcasting by means of rotary antennas using wire dipoles. Two distinct feeder channels respectively leave two transmitters, go through the joint that separates the fixed support from the mobile part of the rotary antenna, then go out horizontally, on either side of the mast, taking support on the bearing structure of the rotary antenna to then rise vertically to the supply points of the dipoles of two distinct vertical groupings of the dipoles: it is thus possible to carry out two simultaneous transmissions from one and the same rotary antenna. Application to broadcasting in decameter waves.

Abstract: A low noise dual polarization electromagnetic power reception and conversion system is disclosed. It comprises a first plurality of conducting elements performing a bandpass function on incident waves, a second plurality of antenna units, located behind the first elements, performing a power reception and conversion function, and a third plurality of conducting elements located behind the antenna units, performing a bandstop function on incident signals. A layer of lossy material is optionally disposed behind the third elements to absorb any wave passing through them. This system can be used to achieve high efficiency power reception and conversion and also reduce levels of radiation of both harmonics of the powering frequency and intermodulation products formed by nonlinear mixing of signal wavefields from other users of the radio spectrum with the powering signal wavefield.

Abstract: A layered antenna is disclosed having at least one radiating element comprising a pair of colinear probes together forming a dipole and a distribution network therefor formed as a single printed conductive pattern layer, a separate metallic layer spaced at a uniform distance from said conductive pattern layer, the metallic layer acting as a ground plane for the distribution network only and further shaped to form a pair of substantially identical parasitic radiating elements for the probes of each radiating element dipole.

Abstract: A surface-mountable antenna is mounted on a substrate at one surface of its dielectric substrate, and is supplied with an RF signal by a feeding part which is provided on the substrate. The dielectric substrate is provided with one feeding through hole and at least one auxiliary through hole in parallel with each other, while a radiating electrode is formed on the inner peripheral surface of the feeding through hole. Further, end electrodes are formed on a surface of the dielectric substrate around the feeding and auxiliary through holes respectively, while an auxiliary electrode is formed on the inner peripheral surface of the auxiliary through hole. Due to this structure, it is possible to provide an antenna which is surface-mountable, has a high gain and controllable directivity.

Abstract: The disclosure relates to broadcasting by means of rotary antennas using rigid dipoles. Each of two distinct channels passes through the joint between the fixed support of the mobile part of the antenna and rise vertically into the interior of the mast to respectively reach two distinct vertical groups of dipoles. It is thus possible to carry out two simultaneous transmissions from one and the same rotary antenna. Application to broadcasting in decameter waves.

Abstract: A multiple layer dipole array that provides for a multi-frequency band phased array antenna. Several layers of dipole pair arrays, each tuned to a different frequency band, are stacked relative to each other along the transmission/reception direction. The highest frequency array is in front of the next lowest frequency array and so forth. Due to the frequency selective property of the arrays, incident high frequency signals are completely absorbed by the highest frequency array. In regard to incident low frequency signals, the insertion loss due to higher frequency arrays is small resulting in good performance of the lower frequency arrays. The multi-frequency band phased array antenna may use active or driven dipole pairs, or parasitic elements that form the multiple layer dipoles. The multiple layer dipole array of the present invention may employ corporate feed circuit boards and a corporate feed power divider, using strip transmission line circuits, for example.

Abstract: The invention provides a broadband directional antenna having a central reflector plate, a dipole and at least one side reflector panel. The dipole is arranged on the central reflector plate for radiating a radio frequency signal, including a binary feed network having a microstrip transmission line and a colinear array of radiating elements. The side reflector panel is hinged to the central reflector plate for adjusting the horizontal radiation beamwidth of the radio frequency signal.

Abstract: A panel antenna suitable for use in cellular communication applications provided with means for mechanically and electrically adjusting the tilt of the antenna beam. Electrical down tilt being achieved by varying the length of a first feed line to a group of dipole pairs. Mechanical down tilting of the antenna beam being achieved by tilting the antenna ground plane and dipole driver assembly with respect to a housing.

Abstract: A dual polarized dipole array antenna for high efficiency power reception or transmission of electromagnetic waves comprises an array of dipole antenna elements and connecting transmission lines, all highly symmetrically arranged each other on a dielectric layer. Rectifiers and wave filters are added to the transmission lines to produce rectified outputs of each dipole antenna element.

Abstract: According to the invention, an antenna curtain, particularly a dipole curtain of an antenna in the decametric wave range is formed of a plurality of cables. Radiators are provided arranged essentially in a vertical plane, defining a radiator plane, in a plurality of rows located one atop another and in one column or in a plurality of columns next to one another. A line system device is provided for feeding the radiators of each column through conductive lines. A single catenary is provided to provide sufficient tension for the vertical or slightly inclined lines of the line system. An approximately horizontal spreader is arranged above each of the columns essentially perpendicularly to the radiator plane. The horizontal spreader is positioned beneath the catenary and above the topmost radiator, preferably spaced a small distance in height above the topmost radiator.

Abstract: Disclosed is an array antenna (10) that may be reconfigured to point in multiple directions. The array antenna includes a driven element (12) coupled to a transmission line (14) and a pair of passive elements (22) and (24). The passive elements (22) and (24) each include three antenna segments that are coupled together by a pair of optoelectronic switches (26) and (28), respectively. When the optoelectronic switches coupled to a particular passive element are closed the element functions as a reflector; when the switches are open, the element functions as a director. Other reconfigurable antennas are also disclosed, including antennas with reconfigurable gain and field pattern characteristics.

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: The present invention provides phased arrays using monolithic technology of diffusions over whole wafers for working in millimetric wave frequency bands. The reflector array includes a plurality of metallizations connected together by diodes whose capacity can be varied. Thus direct control of reactive impedances is obtained. With the metallized strips placed at a distance substantially equal to .lambda./4 from a ground plane, it is possible to control locally the phase of the reflected signal.

Abstract: The antenna has a support with a metallic structure and cables. In order to give the antenna good resistance to wind, it is made by means of rigid half-wave dipoles and these dipoles are mounted directly on the mechanical structure.

Abstract: An antenna comprising a linear array of active elements positioned in one or more rows. The back portion of the array is partially enveloped by a reflector. The reflector includes a backwall and at least one sidewall perpendicular to the backwall and extending forward of the backwall. In one embodiment of the invention, a single row of dipole radiators form the linear array. In a second embodiment of the invention, a row of folded monopoles mounted on an imaging ground plane form the linear array. The radiation pattern is directed forward of the reflector, the back radiation in the E-plane being suppressed by the sidewall of the reflector.

Abstract: An antenna formed by an array of dipole elements fed by a triplate or stripline system is provided with earthed posts between the dipoles. These posts prevent radiation from one dipole being received by others thereby improving the antenna efficiency.

Abstract: A radiating element comprises a groundplane, a dielectric layer and a conductive pattern comprising a folded dipole (20, 21), a feed line (18, 19) for the dipole and a plurality of closely spaced directors (22), all lying in a common plane parallel to the ground plane. An array of such elements with a suitable feed network provides a flat antenna with a squinted beam. The squint angle can be adjusted by adjusting the phase delay between columns of elements. The beam can be steered by selection of the appropriate squint angle and by rotationally adjusting the antenna in its own plane. The antenna is suitable as a less obtrusive alternative to a dish antenna.

Abstract: A dipole antenna system includes a driven dipole element and two parallel parasitic dipole elements equally spaced from the driven dipole element. Dual polarization can also be achieved by using two such systems arranged orthogonally.

Abstract: So as to allow modification of the radiation diagram of a rotary curtain antenna, the doublets of a curtain are distributed in groups of one or several doublets and each group has its own feed line which connects it to a switching box situated in the mast of the antenna and which is constructed so as to bring to the box an impedance inversely proportional to the number of doublets fed by this line; this box allows all or part of the groups of doublets to be fed at will from a mast down line. Dynamic impedance matching cells disposed at the foot of the antenna provide a small standing wave ratio for connection with a transmitter.

Abstract: A method of constructing rotatable scanning prisms (13' and 13") for a multimode detection system (13), each including first and second subprisms (respectively 13'a, 13'b and 13"a, 13"b); the method including the steps of chosing an apex angle for one of said subprisms, determining therefrom apex angles at first and second wavelengths for each of said subprisms, and evaluating whether the differences of apex angles at said several wavelengths are acceptably small.

Abstract: An antenna for a transceiver which does not require a transmit/receive switch, typically a cordless telephone, is formed by a printed circuit board (10) which is subdivided by two separating slits, located in respective separating planes (A, B) into three adjacent regions, defining a first end region (F2) adjacent a first slit, a second end region (F3) adjacent a second slit, and an intermediate or central region (F1) between the slits. Electrical surfaces or conductive tracks are connected across the slits (18, 19) by high-frequency impedance elements, such as high-resistance resistors or chokes, (20, 21).

Abstract: A vertical dipole array (2, 3 to 2.sup.(n), 3.sup.(n)) is formed on a substrate (1) using stripline techniques. The dipoles are supplied with RF energy from a feed system consisting of stripline conductors (4, 4', 5, 6, 7, 7', 9, 12). By a parasitic compensating radiator (11) provided opposite these conductors on the same side of the substrate, the influence of the conductors on the radiation pattern of the dipoles is largely compensated for.The conductors of the feed system are arranged so that a combination of a parallel feed and an equal line length series feed (or, if the radiation pattern is to be raised, a series feed with suitably chosen line lengths) is obtained.

Abstract: Multiband dipole antennas connected to a coaxial feeder are usually not balanced and are not operated at maximum efficiency. In the present invention pairs of capacitors are connected at the feed point of respective half-wave dipoles, associated with different frequency bands to reduce these deficiencies. A similar technique is useful for single band half-wave dipoles and allows unbalanced multiband ground plane antennas to be constructed.

Abstract: The antenna 10 comprises a line of radiating columns 12 extending transversely to the line and a plurality of conducting rods 14 interspersed among the columns 12. The conducting rods 14 are aligned along two lines 22a, 22b to form two reflecting arrays spaced one behind the other with respect to the look direction 11 of the antenna 10. The spacing is one quarter wavelength at the operating frequency.

Abstract: A scannable antenna array especially suited for aircraft having a common reflector and a plurality of spaced apart end-fired Yagi type elements each comprising a driver and one or more director segments spaced mutually from each other and the driver in the direction of the field pattern for the array. In the preferred embodiment, the driver is a dipole comprised of two laterally extending hooked-back radiating segments so dimensioned and spaced from the director elements so as to minimize the mutual electromagnetic coupling among elements of the array. In other embodiments, the driver may comprise a slot.

Abstract: The deviation in operating frequency which antenna system elements can handle without serious transmission line mismatch is increased by constructing the antenna such that the inner portions (40, 42) of its legs (40,48 and 42,50) are formed of coaxial transmission line connected so that the outer conductor serves as part of the radiator, and so that the inner and outer conductor of the line cooperate to form compensation stubs whose impedance varies with frequency in a manner to cancel or oppose the reactance which the antenna legs exhibit with frequency change. The stubs are connected in series or in parallel with the antenna feed point and parasitic elements. Surge impedance is selected so that the antenna driven elements (nearly resistive) and signal source, and parasitic elements that incorporate the invention, are mismatched at band end frequencies and center band frequency in apparoximately like amount.

Abstract: This disclosure is concerned with a linear antenna array mounted on a conductive longitudinal boom, as in a Yagi-type array or the like, having a plurality of assymmetrical transversely extending folded half dipoles and linear extensions thereof disposed at successive longitudinally spaced locations along the boom, with the folded half dipoles of successive antennas extending from opposite sides of said boom.

Abstract: An antenna-radome structure that functions as a self-referencing interferometer, including a radome having a leading edge and including a plurality of longitudinally disposed slabs of dielectric material having a front edge adjacent the leading edge of the radome; and a corresponding number of antennas disposed normal to the longitudinal axis of the radome and respectively embedded in or placed on the surface of each corresponding dielectric slab. Each antenna is located at a distance from the front end of the corresponding dielectric slab corresponding to a maximum of intensity in an intensity fringe pattern produced by interference between free space waves of a predetermined frequency incident upon the dielectric slab and waves guided by the dielectric slab in response to the incident waves. The thickness of each dielectric slab is tapered for reducing sidelobe levels in the far field pattern of the antenna.

Abstract: The improved director (10) of the present invention provides an apparatus and method for increasing the directive gain of an antenna (30), and more particular, for a director in the high VHF band region while reinforcing the low VHF band. The director (10) includes a first element (220) having two symmetrical half sections (222, 224) with inboard ends (240) of each of the half sections mounted to and insulated from the boom (20), a second element (210) having two symmetrical half sections (212, 214) with inboard ends (240) of each half section mounted to an insulated from the boom (20), a pair of opposing phasing lines (230) parallel to the longitudinal length of the boom (20) and separated from each other by a first predetermined distance (410) wherein each phasing line (230) is electrically interconnected with the inboard ends (240) of the first and second element half sections (212 and 222, 214 and 224) located on the same side as the boom (20).

Abstract: An electronically scanned antenna system having a linear array of endfire elements. The endfire elements are laterally spaced between about 0.3 .lambda. to 0.9 .lambda. apart, preferably about 0.55 .lambda. apart, to enhance the effects of mutual coupling therebetween for broadening the radiation signal pattern of the elements in the plane of the array. Advantageously, the endfire elements may be of the Yagi type with each endfire element including a common reflector, a driver, and a plurality of directors.

Abstract: The existence and method of suppression of spurious post mode to improve sidelobe performance of an array of dipole antenna elements together with examples of geometric configuration for suppression of such post mode is described.

Abstract: Disclosed is a radiating source formed by a dipole excited by a flat waveguide which is rectangular in section and is formed by a dielectric sheet having the shape of a rectangular prism whose major and minor faces are each covered with a metal layer of lesser length. The two major faces parallel to the longitudinal midplane are each extended toward the end of the dielectric sheet by means of a metal tongue terminating in one of the stems of the dipole. These stems may be parallel or perpendicular to the direction of polarization of the electric wave radiated by the guide.

Abstract: A multi-band multi-element directional antenna array having a driven element and at least one parasitic element with a network at the center of each element interconnecting element opposite side radiators. While some of these would be a driven element and either a reflector or director parasitic element array most applications call for at least three elements, a driven element, a reflector element and a director element, and for some applications, additional parasitic director elements are added. While antenna arrays embodying features hereof may be adapted as two band f.sub.1 f.sub.2, f.sub.2 f.sub.3, or f.sub.1 f.sub.3 antenna arrays, primary useage would be in a three radio band f.sub.1, f.sub.2, f.sub.3 version with band nominal center frequencies related, approximately by the progression 1, 1.5, 2 (example 14, 21, and 28 MHz).

Abstract: A phased array of dipoles mounted above a ground plane and including capacitance plate elements made of conductive metal mounted at greater distances from ground plane than the dipoles to compensate for variations in impedance over the scan angle of the phase array. With appropriate choice of the dimensions of the capacitance plate, the spacing between the dipole elements and the ground plane, and the spacing between the capacitance plates and the ground plane, the variation of input impedance over the scan angle is greatly reduced for H-plane scan.

Abstract: A corner reflecting antenna is truncated by a reflecting plate. Two rows of ipoles are placed near the throat of the corner reflector (but in front of reflecting plate) and aligned parallel to sides of the antenna. The dipoles are placed at locations that are near multiples of odd quarter-wavelengths from the truncated surfaces. Dipoles lie in the same plane parallel to the truncated surface and equidistant from the sides of the antenna. The rows of the dipoles fed separately by way of two power splitters, a phase shifter and a magic-tee.

Abstract: A stripline horizontally polarized dipole and passive director antenna ar, operative at L-band (1220-1280MHz), mounted in a 90.degree. corner reflector constructed of a grid of cylindrical rods which are hinged along its apex permitting folding of the reflector over the antenna array to protect the elements of the array, for example, during transport.

Abstract: The frequency scanned corner reflector antenna is a modified corner refler antenna that incorporates a feeding technique to achieve monopulse or sequential lobing radiation patterns in one principal plane and one or more frequency-scanned beams in the other principal plane. Scanning of the beam of the corner reflector antenna for direction finding and tracking applications is accomplished without destroying the unique monopulse and sequential lobing capabilities of the antenna.

Abstract: A microwave antenna system particularly adapted for a two channel monopulse adar tracking system having sum and difference feed networks and respective dipole antenna arrays coupled thereto wherein one of the arrays is operated as a passive reflector or director for the other array during the transmit mode but is operated together with the other array as an active receptor during the receive mode whereby sum and difference arrays are provided in order to obtain information necessary to determine angular tracking error signals.

Abstract: A support member mounted on an antenna boom includes a pair of upstanding spaced stanchions for supporting a signal feedthrough wire therebetween. An antenna element is pivotally mounted to the support member and has a bifurcated end which conductively connects with the feedthrough wire when the element is rotated from a folded closed position to an extended open position.

Abstract: The dual scan corner reflector antenna is a frequency scanned antenna for dar, direction finding, or guidance systems which provides increased information gathering capacity over that of prior art systems. The antenna utilizes a helix frequency scanning feed to drive a dipole antenna array. Each output port of the feed is connected to a power divider or combiner to form a common line to the antenna element. At each end of the helix frequency scanning feed are hybrid terminals used to simultaneously form two receive or transmit radiation patterns. The respective helix feed couplers have symmetrical values about the center of the helix feed, allowing the two radiation patterns to be mirror images of each other at the same frequencies. These two radiation patterns can be scanned simultaneously and independently.

Abstract: An antenna primarily for receiving electromagnetic signals and for converting the same to electrical signals for input to a television, FM receiver, or the like, is readily adapted for customizing for maximum efficiency in signal reception at close, normal, and fringe areas relative to the broadcasting antenna. The customized antenna may include elongated generally tubular elements of different sizes, bow tie-shape reflector elements, and/or relatively flat elements, all of which are readily mounted on a support structure that may be attached to an interior or exterior wall, a conventional antenna mast, or the like. Moreover, various ones of the longitudinal elements may be electrically coupled by a conductive harness, and the transmission line leads may be adjustably connected to respective ones of the longitudinal elements. Further, the support structure may include a decorative panel behind which the various signal receiving elements are mounted.

Abstract: A mono-lobed scanner used in a direction finding radar receiver has an antenna in the form of a parabolic dish having four parallel dipole antenna elements which are located physically about the parabola focal point. The outputs of the dipole elements are combined to produce a sum signal, a delta elevation signal and a delta azimuth signal. Pointing or positional inaccuracy of the antenna caused by cross polarization products is corrected by manipulation of metalic rods located about the dipoles and in relatively close proximity thereto.