Abstract: A composite antenna apparatus comprising a balun connected to an inner conductor at the upper end of a coaxial line 11, one end of a helical element formed by a pair of wire conductors is connected to the balun, the other end is wound symmetrically around the coaxial line using the the coaxial line as a center so as to face the balun and is connected to the outer conductor 13 at the lower end of the coaxial line. The provision of an outer conductor connecting terminal connected to the outer conductor and an inner conductor connecting terminal connected to the inner conductor at the lower end of the coaxial line, allows the formation, on the same axis, of a helical antenna fed by the coaxial line via the helical element and a monopole antenna formed by the outer conductor of the coaxial line. Thereby equivalent gain in the horizontal plane and a reduction in the occupied volume is achieved.

Abstract: A dielectric-loaded loop antenna for operation at frequencies above 200 MHz has an elongate cylindrical core with a relative dielectric constant greater than 5, a pair of co-extensive helical antenna elements, a coaxial feeder structure extending through the core from a proximal end to a distal end where it is coupled to the antenna elements, and a balun formed on the core cylindrical surface and connected to the feeder structure at the proximal end of the core. Each helical antenna element is bifurcated at an intermediate position so that proximally, it is formed of two generally parallel branches each of which is coupled to a respective linking path around the core to meet a corresponding branch of the other elongate element therefore forming a conductive loop between the two conductors of the feeder structure. The two conductive loops have different electrical lengths as a result of, for example, the branches being of different lengths.

Abstract: An antenna for use at UHF and upwards has a cylindrical ceramic core with a relative dielectric constant of at least 5. A three-dimensional radiating element structure, consisting of helical antenna elements on the cylindrical surface of the core and connecting radial elements on a distal end face of the core, is formed by conductor tracks plated directly on the core surfaces. At the distal end face the elements are connected to an axially located feed structure in a plated axial passage of the core. The antenna elements are grounded on a plated sleeve covering a proximal part of the core which, in conjunction with the feeder structure, forms an integral balun for matching to an unbalanced feeder.

Abstract: A balanced dipole antenna for a mobile phone comprises a radiator element and a counterpoise, both formed of a conducting material. The counterpoise is electrically isolated from the ground plane of a printed wire board (PWB) of the mobile phone. A matching network, for example, a balun, provides balanced current to the dipole antenna, resulting in a symmetric radiation pattern. The balanced dipole antenna allows superior performance over conventional antennas found in mobile phones today by enabling a user of a mobile phone to communicate effectively and uniformly in all directions, that is, 360 degrees.

Abstract: The present invention discloses an integrated dipole antenna and down converter apparatus. The integrated dipole antenna and down converter apparatus includes a dipole antenna for receiving microwave signals therein. The integrated dipole antenna and down converter apparatus further includes a down converter for receiving processed signals of the microwave signals from the dipole antenna for converting the processed signals to signals of lower frequency. The down converter includes main plate for supporting a tunable mechanical filter. The down converter further includes a tunable semi-mechanical filter supported on the plate. The semi-mechanical filter includes an upper circuit assembly and an identically symmetrical lower circuit assembly for canceling electromagnetic waves transmitting in the upper and lower circuit assemblies and the main plate whereby signal filtering efficiency is improved by reducing signal dissipation in the upper and lower circuit assemblies.

Abstract: A novel means of scanning a circularly polarized reflectarray antenna. The reflectarray is an array of metallic elements arranged on a surface designed to compensate for the various path lengths of the optical rays from an illuminating feed to the reflecting surface and then to the antenna aperture. With appropriate design, the phase in the aperture can be made to vary linearly in any desired direction and also to produce a radiated beam normal to the constant phase surface. In the case of circular polarization, this path length compensation can be accomplished by rotation of the individual elements.

Abstract: An antenna for use with a shippinconductive elements shunt fed to an exterior metallic surface of the container. As a result, electromagnetic field energy is radiated or detected by coupling to currents flowing in the surface of the container, rather than by direct coupling to the radio waves themselves. The shunt fed antenna forms a feed system for the mobile structure. It performs best when mounted on a lower plane of the container adjacent a vertical side, but may be mounted on the vertical side itself in applications where the containers are intended to be stacked upon one another or where vertical polarization properties are desired.

Abstract: An improved antenna system for transmitting and receiving electromagnetic signals comprising a backplane having a length and a vertical axis along the length. A plurality of dipole radiating elements project outwardly from a surface of the backplane. Each of the elements includes a balanced orthogonal pair of dipoles aligned at first and second predetermined angles with respect to the vertical axis, forming crossed dipole pairs. An unbalanced feed network extends along the backplane and connected to the radiating elements. A printed circuit board balun is attached to each of the dipoles. The antenna can also include a parasitic element positioned along the vertical axis such that primary electromagnetic fields induce currents on the parasitic element, these induced currents re-radiate secondary electromagnetic fields which cancel portions of the primary electromagnetic fields, thereby improving isolation.

Abstract: A planar array antenna having radiating elements characterized by dual simultaneous polarization states and having substantially rotationally symmetric radiation patterns. A distribution network, which is connected to each dual polarized radiator, communicates the electromagnetic signals from and to each radiating element. A ground plane is positioned generally parallel to and spaced apart from the radiating elements by a predetermined distance. The conductive surface of the ground plane operates to image the radiating elements over a wide coverage area, thereby enabling a radiation pattern within an azimuth plane of the antenna to be independent of any quantity of radiating elements. Side walls, placed on each side of the array of radiators, can operate in tandem with the ground plane, to reduce the half-power beamwidth in the azimuth plane for a selected radiator design.

Abstract: Double-tuned radiating elements 10 for cellular antennas are configured to enable stamping in one piece from flat sheet metal. Unitary construction incorporates a radiating section 22, an exciter section 14 and a balun section 12 in each radiating element. After the element is formed in one flat piece, a 90 degree bend is made along bend line BL to position radiating section 22 normal to the exciter and balun sections. When mounted in an antenna with the exciter and balun sections 14 and 12 parallel to a conductive ground plane surface, radiating section 22 extends forward normal to the ground plane surface. Radiating section 22 and exciter section 14 are fed by direct coupling to balun section 12, via shared current paths.

Abstract: An antenna array is described in which a feed line that is formed by metal atterns on opposite sides of a circuit board has a plurality of pairs of adjoining quarter wave resonant sections formed by different widths of the patterns and dipoles respectively coupled to the junctions of the pairs of quarter wave sections. The proximity between dipole elements and the feed line is sufficiently close to enable a nearly symmetric azimuthal antenna beam pattern. Each dipole further uses capacitive compensation at its center to balance the capacitive loading with the closely spaced feed line.

Abstract: A directional antenna for telecomunication base station applications for home or business is provided. A folded dipole, a passive reflector, a balun and selectively routed coaxial transmission line all enclosed in a plastic enclosure provide improved stability of operating parameters when subjected to significant installation variations. The use of a PVC or similar plastic enclosure results in increased bandwidth while permitting printed circuit techniques and similar electronic construction methods the necessary protection and structural integrity.

Abstract: An RF data communications device antenna system is shown that includes a dipole and an electromagnetic coupler that provides coupling between each dipole arm to establish a desired resonant bandwidth. An LC matching circuit is provided for matching the dipole to the impedance of the RF data communications device and for transforming the RF signal between the dipole arms of the antenna system.

Abstract: The present invention provides an integrated antenna and phase shifter which has frequency-independent performance. In its preferred form, the antenna phase shifter of the present invention comprises first and second conductive spirals which are identical to and aligned with each other and which are separated from each other by a thin sheet of dielectric material. The first spiral has arms which are connected in a central region of the spiral to a first line of a balun or a balanced transmission line via electronic or optoelectronic switches. The second spiral has arms which are connected in the central region of the second spiral to a second line of the balun or balanced transmission line via electronic or optoelectronic switches. A switching circuit is used to turn them on and off. When any one of the RF switches is turned on, an RF link is established between the arm connected to the switch and the line of the balun connected to the switch.

Abstract: The invention relates to an antenna in stripline technology, in which the dipoles and the feeder network are etched in one single process. The connections of the dipoles are realized as two-wire transmission lines, fed by Schiffman couplers. The polarization of the antenna is selectably chosen by twisting the transmission lines.

Abstract: An improved dipole antenna array with high radiation directivity and broad bandwidth is disclosed. Each dipole antenna is driven by a balun structure composed of an unbalanced J-shaped transmission line placed over a pair of ground plane extensions that are separated by a channel. The dipole antenna arms are connected to an intermediate point on the ground plane extensions so that the balun structure extends beyond the dipole antenna. The length of the dipole arms, their position on the ground plane extensions, and the extent to which the balun extends beyond the dipole antenna can be chosen to determine the desired operating frequency range. The antennas are fabricated on ground and circuit planes separated by a dielectric material and composed of conducting material deposited on dielectric sheets. A planar array of dipole antennas is formed with the ground plane circumscribing each antenna in the array to improve directivity.

Abstract: An E-field generator for r.f. susceptibility testing comprises first and second conductive arms, each comprising a conductor having a U-shaped portion. A driving circuit connected to first ends of each conductor delivers r.f. power to the arms. A load resistance is connected between the opposite ends of the conductors. The U-shaped portions of the elements are disposed opposite each other in spaced relationship so that a device to be tested can be positioned between them. The elements are mounted on a housing which encloses the load resistance as well as a 9:1 balun. The elements are removably secured in clamps, and the housing has provisions for mounting in alternative positions.

Abstract: A balun network is provided having first and second conductor portions symmetric along a center line therebetween. A connecting conductor portion 130 couples ends of the first and second conductor portions with a spacing therebetween. The first and second conductor portions have a like-length of one-quarter wavelength. A balanced port 140 is provided between a first end of the first conductor portion 110 and a first end of the second conductor portion 120. An unbalanced port 150 is provided between a ground reference plane 160 and a first end of the first conductor portion.

Abstract: An antenna for use at frequencies of 200 MHz and upwards has a cylindrical ceramic core with a relative dielectric constant of at least 5, and pairs of helical elements extending from a feed point at one end of the core to the rim of a conductive sleeve adjacent the other end of the core, the sleeve acting as a trap for isolating from ground currents circulating in the helical elements. To yield helical elements of different lengths, the sleeve rim follows a locus which deviates from a plane perpendicular to the core axis in that it describes a zig-zag path. The helical elements form simple helices with approximately balanced radiation resistances.

Abstract: An antenna for use at UHF and upwards has a cylindrical ceramic core with a relative dielectric constant of at least 5. A three-dimensional radiating element structure, consisting of helical antenna elements on the cylindrical surface of the core and connecting radial elements on a distal end face of the core, is formed by conductor tracks plated directly on the core surfaces. At the distal end face the elements are connected to an axially located feed structure in a plated axial passage of the core. The antenna elements are grounded on a plated sleeve covering a proximal part of the core which, in conjunction with the feeder structure, forms an integral balun for matching to an unbalanced feeder.

Abstract: The present invention provides a method (400) and antenna (100) for providing an omnidirectional pattern. The antenna (100) is smaller than prior art omnidirectional antennas with the same bandwidth. The smaller size is made possible by the use of at least one capacitive element (104) at a discontinuity in the loop (102). The pattern is balanced and therefore the omnidirectionality is maintained by the current maximum (110 and 112) that are created by the capacitive element (104).

Abstract: An antenna structure has a rotatable dipole array constituting a driven antenna element, a cup mounted around the dipole, a first conductor connected to and extending from the antenna, and a first dielectric mounted around the first conductor. A second conductor is mounted around the first dielectric, and a second dielectric is mounted around the second conductor. A third conductor is mounted around the second dielectric, and the first and second conductors form a quarter-wavelength transformer. The first dielectric maintains a uniform spacing between the first and second conductors, and the third conductor defines a radio-frequency coupling cavity. The second dielectric electrically enlarges the cavity. Thus the physical dimensions of the structure can be reduced without sacrifice of its electrical properties.

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 small, collapsible, high-gain, dipole antenna and a method to make the antenna. The present invention provides a collapsible half-wavelength dipole antenna for use in a portable device, the antenna having a fully collapsed position and a fully extended position. The antenna includes a static dipole arm, and a movable dipole arm. The movable dipole arm is capable of being moved to the fully collapsed position and the fully extended position. The antenna also includes a balun feed assembly electrically coupled to the static dipole arm and to the movable dipole arm. The antenna is capable of transmitting and receiving electrical signals in either the fully collapsed position or the fully extended position. The balun feed assembly is fixed to the static dipole arm, and the movable dipole arm is movably coupled to the balun feed assembly.

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: An end fed dipole antenna system comprises first and second quarter wavelength (L/4) conductive strips (12, 14) arranged end-to-end on one side of a PCB (16), and third and fourth conductive L/4 strips (22, 24) on the opposite side of the PCB; the third strip (22) overlying the first strip (12) and the fourth strip (24) having a longer arm lying parallel to the third strip (22). An RF generator (18) of wavelength L is connected to the corresponding outer ends of the overlying strips. Strip parts (14, 24) which do not overlie form an end fed dipole which operates as if it were center fed.

Abstract: A printed circuit board antenna is provided which includes an electronic switch (38) whereby a single compact radiating structure consisting of a split dipole antenna (10) with associated balun structure (11) may be selectively driven in either of two modes to provide orthogonal polarization and pattern diversity: as a split dipole antenna with a quarter wave balun relying on the split dipole antenna (10) as the radiating element; or as a top-loaded monopole relying on the quarter wave balun structure (11) as the radiating element against a ground plane (12). Orthogonal polarization and pattern diversity are achieved as a result of the mutually perpendicular orientations of the split dipole antenna (10) and its integral balun structure (11).

Abstract: A television antenna device comprises a pair of electrically conductive dipole arms, a support attached to the dipole arms for supporting the dipole arms, and an electrical circuit operatively connected to each of the dipole arms and mounted to the support for tuning the dipole arms for an optimal impedance match over a plurality of different frequency ranges. A switch is operatively connected to the electrical circuit and is mounted to the support for enabling adjustment of a circuit configuration including the electrical circuit and the dipole arms to selectively tune the dipole arms for an optimal impedance match over the plurality of different frequency ranges. Each of the dipole arms includes a pair of coaxial series tuned circuits for suppressing current flow over electromagnetic frequencies corresponding to higher VHF channels.

Abstract: A deployable antenna assembly includes a canister providing an elongated mber and an elongated hollow mast with a mounting member on its upper end. A coaxial cable extends into the hollow mast to provide radio signals to the antenna assembly of four antenna members of resiliently deflectable members spaced at 90 degree intervals about the periphery of a mounting plate. In the non-deployed position elongated arms extend downward along the inner wall of a canister. A resonant circuit having an inductive coil and a capacitor are located at an intermediate position on the arms. A smooth material is placed between the resonant circuit and the wall of the canister to prevent scraping and damage to the resonant circuit upon deployment. Each opposed pair of antenna element comprises a dipole. A pair of baluns are formed by the arrangement of coaxial cable. A hybrid circuit forming a phase shifter is securely affixed to a mounting plate.

Abstract: A dipole antenna comprises first and second antenna radiators and first and second balanced transmission-line conductors which are electrically connected to the first and second antenna radiators, respectively. An inner conductor and a shield of a coaxial cable are electrically connected to the first and second balanced conductors, respectively to transmit a drive signal to the first and second antenna radiators. A balun is electrically connected to an intersection of the coaxial cable and the first and second balanced conductors. The first and second antenna radiators and the first and second balanced conductors are supported substantially along a common axis such that the first and second balanced conductors separate the first and second antenna radiators from the balun and coaxial cable. The balun can also be supported generally along the same axis.

Abstract: This invention describes a high voltage, very short pulse, microwave radiating source using low-cost components, and capable of operating at high pulse repetition frequencies (prf). The source is activated by an ordinary video trigger commensurate with driving TTL logic. A trigger will cause a chain of N (where N may be 12 or greater) avalanche transistors connected in a Marx generator configuration to threshold resulting in a 1,200 volt or greater baseband pulse having a rise time of less than 100 ps and a duration of about 3 ns driving the input port of a dipole antenna. The dipole is excited by a balun. This invention achieves very short pulse duration broadband microwave radiation at pulse repetition frequencies as high as 30 kHz or greater.

Abstract: A multichannel, multipoint distribution services (MMDS) dipole antenna for receiving multiple channels in the S-band frequency range of 2000 and 3000 MHz is formed from a printed circuit board which is directly connected to a coaxial cable. On the printed circuit board are etched two stacked dipoles. Each of the dipoles has a first one-half element etched on the first side of the printed circuit board and the second one-half element etched on the second side of the printed circuit board. The first and second dipoles are oriented to be in phase with each other and are separated from each other at a wavelength spacing between 0.25 lambda and 0.40 lambda. The antenna of the present invention further uses a phase combining circuit and an impedance matching circuit etched on the printed circuit board for combining in phase the polarized signals, for canceling the non-polarized signals at 0.degree. and 180.degree.

Abstract: Disclosed is an apparatus and method for shaping a beam of radiation from a circularly polarized beam shaping antenna to create a predetermined radiation pattern. A circularly polarized feed horn generates the beam of radiation to be shaped. Circularly polarized radiator elements attached to a ground plane are positioned to receive the beam of radiation. Each radiator element is physically rotated about an axis relative to the ground plane to alter its phase. The radiator elements are then operable to individually radiate a beam of radiation to form a combined radiation beam creating the predetermined radiation pattern.

Abstract: A broadband antenna array, formed of pairs of horizontally-spaced dipoles that are balun-fed, uses an air dielectric microstrip binary-feed network to optimize antenna bandwidth. Each dipole is fed by a three-wire balun which maintains the proper current distribution on the dipoles over the operating bandwidth. The binary-feed network feeds each dipole individually to further optimize the antenna's pattern bandwidth. The binary-feed network is formed using a conductive ground plane with spaced conductors to utilize an air dielectric, thereby minimizing antenna losses in the feed network. The feed network impedances are chosen to give a broadband impedance match to the dipoles, and the entire assembly of binary-feed network and dipoles is mounted in a reflector box, the dimensions of which are chosen to control the antenna beamwidth. Vertically stacked pairs are used to compress the vertical radiation pattern for greater antenna gain.

Abstract: A multichannel, multipoint distribution services (MMDS) dipole antenna for receiving multiple channels in the S-band frequency range of 2000 and 3000 MHz is formed from a printed circuit board which is directly connected to a coaxial cable. On the printed circuit board are etched two stacked dipoles. Each of the dipoles has a first one-half element etched on the first side of the printed circuit board and the second one-half element etched on the second side of the printed circuit board. The first and second dipoles are oriented to be in phase with each other and are separated from each other at a wavelength spacing between 0.25 lambda and 0.40 lambda. The antenna of the present invention further uses a phase combining circuit and an impedance matching circuit etched on the printed circuit board for combining in phase the polarized signals, for canceling the non-polarized signals at 0.degree. and 180.degree.

Abstract: A folded broadband antenna provides a symmetrical radiation pattern comparable to corresponding planar antennas (such as a planar spiral). The folded antenna can be integrated into a leading edge radome, eliminating the forward antenna cavity, and thereby, eliminating the internal wall reflections that cause radiation pattern distortion. A broadband antenna (61/62), such as an archimedean spiral, is folded at an apex area (64) that includes a fold-slot (66). The fold-slot enhances flexure, and allows a center-feed balun shielding tube (84) to extend into close proximity to the antenna aperture (61) for increased balun shielding.

Abstract: An omnidirectional antenna provides circular and elliptically polarized electromagnetic waves. The antenna constitutes first and second elements as the only radiating portions of the antenna. Each element has an elongated central portion parallel to each other, with ends bent at a predetermined slant angle above and below horizontal planes running through the central portions, and then with the ends themselves being at acute angles with respect to the central portion. The acute angles of the second element are in opposite orientation to the first. A proper balun is provided for driving the antenna.

Abstract: A deployable antenna assembly includes a canister providing an elongated chamber and an elongated hollow mast with a mounting member on its upper end. A coaxial cable extends into the hollow mast to provide radio signals to the antenna assembly and four antenna members of resiliently deflectable wire spaced at 90 degrees intervals about the periphery of the mounting plate comprise a generally helical coil and elongate arms extending downwardly along the inner wall of the canister, and each opposed pair comprises a dipoles. A pair of baluns are connected to the coaxial cable and disposed adjacent the mounting member, and a phase shifter are connected between the coaxial cable and one of the baluns. Connectors conductively connect the central conductor of the balun to the coil of one of the antenna members of a dipole, and the conductive shield to the coil of the other antenna member of a dipole. A sealing medium is provided about the baluns, and phase shifter.

Abstract: In a printed circuit embodiment, dielectric boards in a multilayer arrangement have their ends protruding from a ground plane. Sets of printed dipole elements are disposed along the edge of each board. Each set of dipole elements has three feed ports. Bandpass filters are provided for each feed port. Phase shifters are coupled to each of the feed ports through its respective bandpass filter. At the low band, the outer feed ports are shorted by the filters so that the two sections of dipole elements to the left of the center feed port form one lone band dipole arm, and the two sections of dipole elements to the right of the center feed port form the other low band dipole arm. The low band dipole is driven at the center feed port. At the high band, the center feed port becomes an open circuit so that the two sections to the left thereof form one high band dipole, and the two sections to the right thereof form a second high band dipole. The two outer feed ports drive the dipole array at the high band.

Abstract: A means for feeding or extracting radio frequency energy from an antenna element which uses coaxial transmission line, without upsetting the antenna elements physical or electrical symmetry, thus providing improved standing wave ratios and near theoretical radiation patterns. Because coaxial cable is inherently unbalanced, double reactance cancellation and resistance transformation are integrally provided by a feed loop shunted across the antenna element improving performance.

Abstract: This Yagi-Uda-type antenna includes also a sleeve embracing the dipole. The sleeve may be a closed cylindrical element surrounding the dipole or it may comprise a pair of discrete elements forming an "open sleeve". The dipole, sleeve, reflector, and director elements may be in filamentary form, or they may be fabricated from stripline.

Abstract: A miniature microstrip dipole antenna is constructed on a high permitivity dielectric substrate for compactibility with microwave monolithic integrated circuit (MMIC) technology. The antenna comprises two dipole arms coupled to opposite faces of the substrate. The dipole arms are coupled to a microstrip transmission line through a tapered balun. The tapered balun comprises two conductors on opposite faces of the substrate which are coupled to corresponding dipole arms. The conductors are separated laterally (with respect to the width of the face of the substrate) a calculated distance, and are gradually tapered. This allows the balun to efficiently transform unbalanced signals at the microstrip transmission line to balanced signals at the plurality of dipole arms. Alternatively, the balun allows balanced signals at the dipole arms to be efficiently transformed to unbalanced signals at the microstrip transmission line.

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 microstrip fed printed dipole with an integral balun is disclosed, fabricated upon a planar dielectric substrate by patterning metallizations disposed on the two surfaces of the substrate. In the arrangement, the ground plane of the unbalanced microstrip transmission line is bifurcated by a central slot to form a balanced transmission line coextensive with the slot which becomes a part of the arms of the dipole and which at the same time serves as the ground plane of a continuation of the microstrip feed. A continuation of the strip conductor of the unbalanced microstrip feed having a "J" shaped configuration continues over the bifurcated ground planes and crosses the slot in proximity to the dipole for effecting an efficient unbalanced feed to the balanced dipole. The arrangement has a double tuned characteristic with two available and independent adjustments facilitating reproducable, optimized broadband performance.

Abstract: An improved element for use in an electrically steered antenna array is disclosed comprising a dipole, an integral balun and a 180.degree. phase shift bit. The arrangement utilizes printed circuit techniques throughout using an unbalanced microstrip for connection to electrical circuitry, a balun for transitioning from unbalanced microstrip to a balanced dipole antenna and includes a low loss 180.degree. phase shift bit formed by the use of a branched feed network including two diodes whose conductive states determine the sense of antenna excitation, and produce the equivalent of a 180.degree. phase shift bit.

Abstract: An balun-antenna arrangement is provided which is capable of being fabricated on a printed circuit board by automated equipment. The balun-antenna includes a microstrip transmission line which is coupled to one end of a split microstrip transmission line having opposed ends. An antenna which is symmetric about its feedpoint is coupled to the remaining end of the split microstrip transmission line.

Abstract: In general a coaxial feeder connected directly into the center of a half-wave dipole antenna disturbs electrical balance and therefore reduces the effectiveness of the screen of the feeder. In the present invention a dipole with two quarter-wavelength elements symmetrically connected through respective identical capacitors to the screen of the feeder is fed through an inductor connected to the junction between one element and its capacitor. By having equal reactances, the capacitors balance the dipole to earth and by means of its phase delay the inductor restores a resistive impedance termination for the feeder.

Abstract: A dipole phase shifter for use in a phased array antenna includes an insulating substrate having first and second sides. A dipole element having first and second conductive dipole arms is formed on the first side of the insulating substrate and a PIN/NIP diode pair is mounted on the second side of the insulating substrate and electrically-connected to the first and second dipole arms, respectively. A coaxial RF transmission line having a center conductor extending through the insulating substrate connects an input signal to the phase shifter. Quarter-wave transformers are connected between the center conductor and the diodes to compensate for the forward and reverse bias reactances thereof. The first and second dipole arms serve as groundplanes for the quarter-wave transformers. The center conductor also serves as a common bias line which allows forward biasing of one diode and, simultaneously, reverse biasing of the other diode.

Abstract: An antenna for providing a vertically polarized omnidirectional horizontal radiation pattern comprising colinear dipoles. Suitable feeding arrangements are provided for electromagnetically feeding the dipoles with a signal. An axially extending conductive member is spaced on either side of the colinear dipoles. The axis of each of said conductive members as well as the axis of the dipoles are colinear and parallel.

Abstract: A one-piece array antenna dipole radiating element is formed from a wide, thin conductor. This element is suitable for attachment to a microstrip or other feed circuit. The radiation element includes a dipole portion, a balanced transmission line portion and a balun portion. These various portions are formed by providing an appropriately shaped slot in the thin conductor.